Lofa EP250 Operating instructions

EP250™Panel Operation
and Troubleshooting
463-3000-01 24-May-13 1
© 2006-2013 LOFA Industries, Inc. All rights reserved.
LOFA, the LOFA logo, CANplus and EP250 are trademarks of LOFA Industries, Inc. All rights reserved.
Windows is a registered trademark of Microsoft Corporation.

EP250 Panel Operation and Troubleshooting
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SAFETY SYMBOLS
This manual uses the following conventions to present IMPORTANT SAFETY INFORMATION to you.
Please read and follow ALL SAFETY INSTRUCTIONS.
IMPORTANT SAFETY INFORMATION- A HAZARD THAT MAY,
IF NOT AVOIDED, CAUSE MINOR/ MODERATE INJURY.
IMPORTANT SAFETY INFORMATION- A HAZARD THAT
MIGHT CAUSE SERIOUS INJURY OR LOSS OF LIFE.
IMPORTANT and URGENT SAFETY INFORMATION- A
HAZARD THAT WILL, IF NOT AVOIDED, CAUSE SERIOUS
INJURY OR LOSS OF LIFE.
CAUTION
IMPORTANT SAFETY INFORMATION- A HAZARD THAT MAY,
IF NOT AVOIDED, CAUSE EQUIPMENT DAMAGE.
NOTE
ADDITIONAL IMPORTANT INFORMATION.
This document must be completely read and understood prior to installing, testing, or operating
the equipment described within. Further, this document must be retained for current and future
users of this equipment. Failure to strictly follow the warnings and dangers presented within this document could
result in damage to equipment, damage to property, bodily injury or death.
NOTE: THE SELLER HEREBY EXPRESSLY DISCLAIMS ALL WARRANTIES, EITHER EXPRESSED OR IMPLIED, INCLUDING ANY
IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, AND NEITHER ASSUMES NOR
AUTHORIZES ANY OTHER PERSON TO ASSUME FOR IT ANY LIABILITY IN CONNECTION WITH THE SALE OF SUCH
PRODUCTS.
LOFA products are not designed or approved for use as critical components of any safety device or system
that is intended to prevent bodily injury, protect life, or prevent property damage.
The specifying Original Equipment Manufacturer (OEM) and/or Installer of any LOFA panel is responsible
for all safety labeling and operator education regarding the safe operation of this panel and the operation
of the specific machine that this panel is installed upon—including conformance to exhaust emissions regulations.
Only trained and qualified persons may perform installation, testing, service, or repair work on the LOFA
product.
LOFA products are not designed for, or intended for use on applications requiring explosive proof
components. Further, LOFA products are not designed for, or intended for application within hazardous or
explosive environments.
The installer of this LOFA product is solely responsible for ensuring that all OSHA, ANSI, CE, or other
applicable standards are met with respect to LOFA panel applicability, machine guarding, general safety
guidelines, labeling, and warnings.
The installer of this LOFA panel and/or LOFA harness is responsible for sizing and integrating a
suitable fuse/ breaker on the un-switched DC circuit supplying power to the LOFA panel.
NOTE: Please refer to www.LOFA.net for details on LOFA Industries, Inc. warranty policies.
LOFA Industries, Inc. has provided this document as a reference. We try to keep this document updated with the latest information regarding your LOFA product. However, changes do
occur and LOFA reserves the right to make changes to the design of the LOFA products and supporting documentation without notice.

EP250 Panel Operation and Troubleshooting
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NOTE: GENERAL EMISSIONS DISCLAIMER
This panel may include provision(s) for operator input such as FORCE REGENERATION, INHIBIT
REGENERATION, INTERLOCK, and others specific to US and International emissions regulations.
Responsibility for emissions related inputs and compliance with emissions regulations is solely that of
the owner and/or operator of the machine/ engine on which this panel is connected.
TYPICAL OPERATION:
1. Pull the AUX Engine STOP button “OUT” (away from the
panel face) to allow engine operation.
2. Push the AUX Engine STOP button “IN” (toward the
panel face) to initiate an AUXILLIARY Engine Stop.
AUXILIARY Engine Stop DISCLAIMER
This panel or harness may include an optional Auxiliary Engine Stop feature. The sole design intent of the Auxiliary
Engine Stop Feature is to provide for engine shutdown in the event of a key-switch malfunction. The panel key/
lever switch should always be used as the primary engine shutdown method.
Please note that the Auxiliary Engine Stop feature is NOT intended to function as the machine/ equipment
Emergency Stop, or be purposed as an Emergency Stop for safety purposes. The machine manufacturer must
provide a separate Emergency Stop switch to meet safety mandates or emergency machine shutdown
functionality.
AUTO- Start DISCLAIMER
This panel/machine may be equipped with an automatic engine start-up
system that could result in the automatic starting and stopping of the
engine/ machine at any time. As such:
The engine may start without warning or notice.
It is SOLELY the responsibility of the owner/ installer/ operator to provide
warning labels, visible warnings, and audible warnings to notify the
operator of an impending start-up.
ALWAYS use lockout/ tag out procedures prior to performing ANY
service or configuration operations.
DO NOT configure operator programmable features while the panel is in
“AUTO” mode (Key in auto-start position). The panel should be
configured ONLY when the key is in the “Run” position.

EP250 Panel Operation and Troubleshooting
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Introduction
This document provides general information on LOFA™ EP250 panel operation and troubleshooting. EP250
control panels are a flexible platform for diesel engine control, monitoring, and protection, featuring
LOFA’s powerful First Fault Diagnostics (FFD). After pinpointing the initial failure, FFD stores it in memory
and alerts the end user via a single bright LED. FFD monitors battery charge, low oil pressure, high
temperature, over speed and up to three additional contact closure inputs. The field configurable,
expandable microprocessor-based solid-state design uses high-power semiconductors instead of outdated
electromechanical relays to ensure reliable high-current switching.
Some of the EP250 configurable features include:
Automatic preheat duration
Afterglow duration
Failure indication with shutdown or indication only
Over-speed shutdown
Normally open or normally closed shutdown switches
The EP250 features LOFA’s new modular Function Enhancement Packs (FEP). The plug-and-play FEP
modules allow various feature upgrades to be easily added to the standard platform. FEPs include:
Automatic Start/Stop Operation
Precision Actuator Control
Custom OEM Solutions
All standard panels include feature a 12 inch wiring harness terminating into a sealed weather proof plug.
This robust universal wiring connection performs well in harsh environments and allows interchanging a
number of different panels and harnesses. This design allows for simplified installation as well as a flexible
means to incorporate custom plug-and-play engine wiring harnesses and standard harness extension
Note
The engine harness is not included with the panel.
A number of standard engine harnesses are available or
LOFA can develop a custom harness for you exact needs.
Generic harnesses in various lengths are available for field customization.
CAUTION: EXHAUST EMISSIONS COMPLIANCE/ AUTO-START DISCLAIMER
This panel is equipped with operator programmable parameters that could result in the automatic
starting and stopping of the engine/ machine. The engine/ machine, as a function of the emissions
system can/ could initiate, via the engine ECU, certain required emissions operations such as
regeneration of the DPF, or other emissions system maintenance, while the engine is running. The
owner/ operator of the engine/ machine is solely responsible for any adverse effects or damage to the
engine, engine emissions system, or other damage that could occur as a result of starting or stopping
the engine/ machine during any ECU initiated emissions event.

EP250 Panel Operation and Troubleshooting
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Warning!
When replacement parts are required, LOFA Industries recommends using replacement
parts supplied by LOFA or parts with equivalent specifications.
Failure to heed this warning can lead to premature failure,
product damage, personal injury or death.

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Operation
Turning the panel key to the run position starts a self-test which causes all LEDs to illuminate once,
activates the alarm output for one second and enables the fuel run/stop solenoid output. After self-test,
the LEDs indicate the state of the inputs they monitor. The normal indications are battery charge and oil
pressure on most applications. If these LEDs are not illuminated at this time it may indicate the inputs are
not properly connected.
The Preheat LED is illuminated when the key switch is turned to the run position if automatic preheat is
configured or if an external preheat control is connected (See Preheat Options). Preheat time varies from
application to application. After waiting for the Preheat LED to extinguish, the engine is cranked by turning
and holding the key switch in the start position until the engine starts. The key switch is spring loaded to
return automatically to the run position when released. The Preheat LED is illuminated during afterglow if
enabled.
Note
The key switch is equipped with a mechanical start locking device.
An attempt to crank the engine again can only be made by turning the key switch
to the off position to reset the start locking mechanism.
If the engine is not started within 10 seconds of turning on the panel, the fuel run/stop solenoid output is
turned off to prevent battery discharge when the key switch is left in the run position. The fuel run/stop
solenoid output is turned off after 10 seconds even if preheating. As soon as the key switch is turned to
the start position the solenoid output is enabled. The afterglow cycle begins when the key switch returns
to the run position.
Note
If conditions do not warrant preheat, the engine may be started by turning the key to the
start position without waiting for the preheat time to expire.
Panel instrument power, including the hour meter and voltmeter, is provided by the fuel run/stop solenoid
output. If the instruments do not power up when the key is turned to the run position, this indicates a
problem with the solenoid circuit (see Troubleshooting).
After the engine starts, the panel electronics ignore all shutdown conditions for the first 10 seconds. This
delay eliminates the requirement to hold a by-pass override button during starting and allows the
conditions such as oil pressure to normalize. The 10 second timer starts when the key switch returns to the
run position.
Note
Starter input is required for correct panel operation. If the starter motor input is not
activated (connected to battery positive) and the engine is started through another means
(i.e. air starter) the engine will shutdown 10 seconds after the key switch is turned to the run
position.

EP250 Panel Operation and Troubleshooting
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To prevent unintentional engine shutdowns caused by intermittent conditions (i.e., pressure spikes, coolant
movement) the panel requires a constant 1 second fault input to cause engine shutdown.
Warning!
When used in combination with mechanical float type switches
engine vibrations may prevent constant contact closure.
The panel can be configured to shutdown with no delay.
The panel has the ability to shut down the engine for over speed. Over speed will be indicated via a
blinking Battery Charge LED. The panel senses RPM either by the frequency terminal of the alternator,
proximity switch or magnetic pick-up with the optional magnetic pick-up amplifier/divider.
Preheat Options
Preheat Output
Preheat is a 750 mA output for control of an external power relay with predetermined preheat and
afterglow times. A relay should be selected with appropriate amperage capacity for the installed cold
starting aid (glowplug, intake air heater, etc.). Applications using multiple cold starting aids may require
multiple relays. Depending on specific configuration, this output may provide either high side (battery
positive) or low side (ground) control.
Note
Consult engine documentation when selecting cold starting aid,
power relay and heating specifications.
Preheat Indication Input
With this option, the preheat LED provides indication for an external preheat control. Depending on
specific controls and configuration, this input can be configured to accept either high side (battery
positive) or low side (ground) control.
Indicators
Battery LED (Red)
A solidly illuminated Battery LED indicates a battery charge failure. A battery charge failure may be caused
by a faulty alternator, broken drive belt or the alternator not excited. A battery voltage reading of
approximately 14 volts on a 12 volt system (28 volts on a 24 volt system) while the engine is running
indicates the battery is charging properly. Irregular blinking of the Battery LED may indicate a failing
charge circuit. The panel can be configured for battery charge failure to indicate only.
Over Speed Indication
A regularly blinking Battery LED indicates the configured over speed RPM has been exceeded. Over speed
is a configurable option that is disabled by default.

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Oil Pressure LED (Red)
A solidly illuminated Oil Pressure LED indicates low oil pressure failure. The panel typically senses low oil
pressure from a ground contact switch on the engine. When a sender/switch combination is used on the
engine, the marking WK generally indicates the switch terminal. This input typically expects a normally
closed switch (ground contact when oil pressure is low). A defective switch or shorting the shutdown input
to ground can cause low pressure fault indication. Additionally, when using sender/switch combinations,
swapping the WK and G terminal can cause unintended shutdowns. The panel can be configured for oil
pressure failure to indicate only.
Warning!
Low oil pressure is not an indication of low oil level.
For best possible protection LOFA recommends using
our solid-state oil level shutdown switch.
Note
Most shutdown switches are grounded through the switch body.
Do not use insulating sealant (i.e. Teflon tape) when installing switches.
Temperature LED (Red)
A solidly illuminated Temperature LED indicates high engine temperature failure. The panel typically senses
high temperature from a ground contact switch on the engine. When a sender/switch combination is used
on the engine, the marking WK or W generally indicates the switch terminal. This input typically expects a
normally open switch (ground contact when engine temperature is too high). A defective switch or
shorting the shutdown input to ground can cause over temperature fault indication. Additionally, when
using sender/switch combinations, swapping the WK or W and G terminal can cause unintended
shutdowns. The panel can be configured for temperature failure to indicate only.
Warning!
If the temperature switch is not in contact with coolant due to
coolant loss the engine is not protected from overheating.
For best possible protection, LOFA recommends using
our solid-state coolant level shutdown switch.
Note
Most shutdown switches are grounded through the switch body.
Do not use insulating sealant (i.e. Teflon tape) when installing switches.
Some thermostat housings are composites and do not provide ground for the switch.
AUX 1 LED (Red)
A solidly illuminated AUX 1 LED indicates auxiliary 1 failure (i.e., coolant level, oil level, belt breakage,
hydraulic pressure, etc.). The panel typically senses failure using a ground contact switch. Auxiliary inputs
are equipment specific and determined by the equipment manufacturer. A defective switch or shorting the

EP250 Panel Operation and Troubleshooting
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shutdown input to ground can cause fault indications. The panel can be configured for auxiliary 1 failure to
indicate only.
A blinking AUX 1 LED indicates SW input failure. The panel typically senses failure using a ground contact
switch. The SW input is equipment specific and determined by the equipment manufacturer. A defective
switch or shorting the shutdown input to ground can cause fault indications.
AUX 2 LED (Red)
A solidly illuminated AUX 2 LED indicates an auxiliary switch 2 fault (i.e., air flow restriction, fuel level, etc.)
but by default does not cause a shutdown. The panel typically senses failure using a ground contact switch.
Auxiliary inputs are equipment specific and determined by the equipment manufacturer. A defective switch
or shorting the shutdown input to ground can cause fault indications. The panel can be configured with
auxiliary 2 shutdown.
Preheat LED (Red)
A solidly illuminated Preheat LED is the panel preheat indication. When the LED extinguishes the preheat
period is complete and the engine may be cranked. The LED illuminates again to indicate afterglow.

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Gauges
Voltmeter
The voltmeter is connected to the fuel run/stop solenoid output. If the voltmeter does not indicate in the
run position, this indicates a problem with the solenoid circuit. A battery voltage reading of approximately
14 volts on a 12 volt system (28 volts on a 24 volt system) while the engine is running indicates the battery
is charging properly.
Tachometer
The tachometer indicates engine RPM using a frequency signal derived from the engine. This signal may
be provided by an alternator frequency tap, proximity switch. An optional amplifier/divider can be added
for use with a magnetic pickup.
Note
If the alternator is not excited (not charging),
no frequency is generated and the tachometer will indicate 0 RPM.
The tachometer must be calibrated to the engine using standard procedures (see Tachometer Calibration
Instructions for details).
Oil Pressure Gauge
The gauge measures oil pressure with a resistance sender on the engine referenced to ground. When a
sender/switch combination is used on the engine, the marking Ggenerally indicates the gauge terminal.
The gauge expects a low resistance for low pressure and a higher resistance for higher pressure. If a
powered gauge is not connected to the sender, the gauge will read full scale (pegged). A defective sender
or shorting the gauge input to ground will cause the gauge to read no pressure. When using
sender/switch combinations, swapping the WK and G terminal prevents the gauge from working and may
cause unintended shutdowns.
Warning!
Low oil pressure is an indication of engine wear,
not an accurate indication of low oil level.
Note
Senders and gauges must be matched to indicate correctly.
Most senders are grounded through the sender body.
Do not use insulating sealant (i.e. Teflon tape) when installing senders.
Temperature Gauge
The gauge measures engine temperature with a resistance sender on the engine referenced to ground.
When a sender/switch combination is used on the engine, the marking Ggenerally indicates the gauge
terminal. The gauge expects a high resistance for low temperatures and a lower resistance for higher

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temperatures. If the gauge is not connected to the sender, the will be on read the minimum reading. A
defective sender or shorting the gauge input to ground will cause the gauge to read full scale (pegged).
When using sender/switch combinations, swapping the WK and G terminal prevents the gauge from
working and may cause unintended shutdowns.
Warning!
If the temperature sensor is not in contact with coolant due to coolant loss
the gauge will not accurately indicate engine temperature.
Note
Senders and gauges must be matched to indicate correctly.
Most senders are grounded through the sender body.
Do not use insulating sealant (i.e. Teflon tape) when installing senders.
Some thermostat housings are composites and do not provide ground for the sender.
Hourmeter
The hourmeter is connected to the fuel run/stop solenoid output. If the hourmeter does not count in the
run position, this may indicate a faulty hourmeter or a problem with the solenoid circuit. If the engine
shuts down or is not started within 10 second, the hourmeter stops counting.
Additional Gauges
Additional gauges can be added by removing blind covers and installing the gauge. Power connections are
provided with the standard configuration.

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Harness
Sealed Connectors
The provided sealed weather proof plug includes a grey locking device which must be released to separate
the connectors. Press the tab on the connector housing to release the connectors.
Warning!
LOFA does not recommend using dielectric grease or sealant with sealed connectors.
These chemicals may cause seal damage and allow water entry.
Use LOFA provided cavity plugs to seal the connector if wires are removed.
Unsealed Connectors
For unsealed connectors exposed to the elements, LOFA recommends using dielectric grease to protect
contacts.
Warning!
LOFA does not recommend using sealant with unsealed connectors.
Sealant traps moisture in the connector and encourages corosion.
Harness Routing
The minimum routing of radius of the wiring harnesses should be at least two times the diameter of the
wiring harness. Bends should be avoided within 1 inch (25 mm) of any connector in order to avoid seal
distortion allowing moisture to enter the connector.
Note
For harness length in excess of 10 ft a relay must be added to the start solenoid circuit.
A relay may also be required for the fuel run/stop solenoid.
LOFA offers starter relay kits for mounting near the engine.

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Battery Circuit Requirements
Battery Positive Connection
The electronic panel operates on either a 12 VDC or 24 VDC electrical systems. The unswitched battery
positive connection to the panel is made at the weather proof connector. The panel provides switched
positive battery protected by a 15 Amp fuse (12 V or 24 V systems).
Protection for the unswitched battery positive circuit is dependent on specific equipment configuration.
The overload protection should not exceed 125% of the sum of all output currents plus 5 Amps for the
panel. Powering the panel through dedicated circuits with appropriate overload protection reduces the
possibility of panel damage.
Circuit breakers are preferred over in-line fuses for circuit protection. Over current protection devices
should ideally be located in a central location. If automatic reset circuit breakers are used, consideration of
the environment of the breaker is critical and may affect the trip point. The trip point of some circuit
breakers can be significantly reduced below the rated trip point if the circuit breaker is exposed to high
temperatures.
Warning!
Disconnecting the battery while the engine is running
may damage electrical components.
When using a battery disconnect switch, LOFA recommends using a
2 pole switch to disconnect both the battery and alternator output.
Battery Negative Connection (Grounding)
Warning!
Improper grounding can cause electrical noise, unreliable operation and may damage the
panel or other components. All ground connections must be free from foreign materials,
including paint, which may interfere with proper grounding.
A reliable ground must be provided for the panel.
LOFA recommends the ground connection be made directly to the battery negative.
Grounding through frame members is not recommended.
All ground paths must be capable of carrying any likely fault currents.
Do not reverse the battery polarity. Attempting to crank the engine when the polarity of the
battery connections is reversed may damage the panel.
Note
A maximum of three ring terminals should be connected to a ground stud in order to
ensure integrity of the ground connection. The use of more than three terminals can cause
the connection to become loose.
Voltage Drop
If panel voltage drops below 6 volts for more than one tenth of a second, the panel may reset causing the
self-test to reactivate and the engine to shut down after 10 seconds. Resetting the panel is equivalent to

EP250 Panel Operation and Troubleshooting
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quickly turning the key switch to off and back to run without starting the engine. Since the panel did not
sense a start signal, the fuel run/stop solenoid deactivates after 10 seconds. Voltage drops can be caused
by external equipment inrush current, improper wire sizes or faulty wiring. Relays may be needed for long
wire runs.
Suppression of Voltage Transients (Spikes)
Warning!
The installation of voltage transient suppression at the transient source is required.
LOFA follows SAE recommended electrical environment practices.
Inductive devices such as relays, solenoids and motors generate voltage transients and noise in electrical
circuits. Unsuppressed voltage transients can exceed SAE specifications and damage electronic controls.
I
Relays and solenoids with built-in voltage transient suppression diodes are recommended whenever
possible. Refer to the illustration for proper installation of diodes when built-in voltage transient
suppression is not available.
Locate inductive devices as far as possible from the components of the electronic panel. When using
electric motors it may also be necessary to add isolation relays to eliminate voltage transients, noise and
prevent back feed.
Note
LOFA harness assemblies typically include all required engine control suppression devices.
Added equipment will require additional protection.

EP250 Panel Operation and Troubleshooting
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Welding on Equipment with Electronic Controls
Proper welding procedures are required to avoid damage to electronic controls, sensors, and associated
components. The component should be removed for welding if possible.
The following procedure must be followed if the component must be welded while installed on equipment
with electronic controls. This procedure will minimize the risk of component damage.
Warning!
Do not ground the welder to electrical components such as the control ground or sensors.
Improper grounding can cause damage to electrical components
Clamp the ground cable from the welder to the component being welded. Place the clamp
as close as possible to the weld to reduce the possibility of damage.
1. Stop the engine. Turn the key switch to the OFF position.
2. Disconnect the negative battery cable from the battery.
3. Open any installed battery disconnect switch.
4. Unplug the panel if possible.
5. Connect the welding ground cable as close as possible to the area to be welded.
6. Protect the wiring harness from welding debris and spatter.
7. Use standard welding methods to weld the materials.

EP250 Panel Operation and Troubleshooting
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General Troubleshooting
For additional information, refer to engine manufacturer troubleshooting guide.
No response from starter motor
Possible Cause
Possible Remedy
No battery voltage to starter
Verify wiring and battery connection (power and ground)
Battery discharged
Charge or replace battery, verify alternator charging
Tripped overcurrent
protection
Correct fault, replace or reset overcurrent protection
No signal from panel
No power to panel (see Panel Troubleshooting below)
Defective starter solenoid
Replace starter solenoid
Defective starter motor
Replace starter motor
Engine will crank but not start
Possible Cause
Possible Remedy
Engine not getting fuel
Check fuel level, filter, fuel pump, verify no air in fuel lines
Fuel run/stop solenoid not
engaged
See Fuel Solenoid Run/Stop Troubleshooting (below)
Tripped overcurrent
protection
Correct fault, replace or reset overcurrent protection
No preheat (cold condition)
See Preheat Troubleshooting
Engine runs for 10 seconds and shuts down
Possible Cause
Possible Remedy
Shutdown switch input active
Verify shutdown source exists, correct condition or correct faulty circuit
Battery not charging
Verify alternator charging (see Alternator not charging battery below)
Control board did not sense
start signal
Engine started through alternate method (i.e., manual air start, push start,
etc.)
Defective panel
See Panel Troubleshooting (below)
Engine runs longer than 10 seconds and shuts down
Possible Cause
Possible Remedy
Shutdown switch input active
Correct engine fault, verify shutdown switch wiring
Circuit overload protection
tripped
Correct overload, keep panel from overheating
(over 185° F/85° C)
Voltage transients (spikes)
Add suppressor diodes, protect from nearby lightning strikes, shield
induced spikes from other equipment, add electric motor control relay
Defective panel
See Panel Troubleshooting (below)

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Alternator not charging battery
Possible Cause
Possible Remedy
Broken or slipping alternator
drive belt
Adjust or replace alternator drive belt
Alternator not excited
Verify excitation circuit connected, replace faulty regulator, add additional
excitation resistor
Alternator output not
connected
Install charge wire
Alternator not grounded
Clean or add ground connection
Alternator faulty
Replace faulty alternator
Fuel Run/Stop Solenoid Troubleshooting
Engine does not stop immediately
Possible Cause
Possible Remedy
Back feed from motor (i.e.,
cooling fan)
Add relay or blocking diode
Sticking solenoid linkage
Repair or replace solenoid linkage
Fuel valve without check valve
Install or repair check valve
Fuel run/stop solenoid does not engage
Possible Cause
Possible Remedy
No power to solenoid
Locate reason for lack of power and correct (Circuit overloaded? Failed
suppressor diode? Faulty wiring?)
No power to solenoid pull coil
Correct faulty wiring, check pull control circuit (see Power Box
Troubleshooting below)
Incorrect linkage adjustment
Adjust solenoid linkage
Faulty solenoid
Replace solenoid
Failed suppressor diode
Correct wiring (diode reversed?), replace suppressor diode
Optional e-stop engaged
Disengage e-stop
Engine not getting fuel
Possible Cause
Possible Remedy
Empty fuel tank
Fuel engine
Clogged filter
Replace filter
Air in fuel lines
Bleed fuel lines
Low fuel pressure
Replace faulty fuel pump and/or clogged filter
Faulty fuel pump
Replace fuel pump, correct wiring fault (electric fuel pump)

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Preheat Troubleshooting
Engine is hard to start in cold conditions
Possible Cause
Possible Remedy
Start attempt before preheat
complete
Wait for preheat time to elapse, crank as soon as time elapses
Incorrect preheat specification
Correct panel configuration, install correct panel
Heater faulty
Replace heater
Heater relay faulty
Replace relay
Preheat control not
functioning
Correct wiring, correct panel configuration
Faulty panel
See Panel Troubleshooting (below)
Engine produces excessive white smoke after starting
Possible Cause
Possible Remedy
Afterglow not enabled
Reconfigure panel
Heater faulty
Replace heater
Heater relay faulty
Replace relay
Preheat control not
functioning
Correct wiring, correct panel configuration
Faulty panel
See Panel Troubleshooting (below)
Panel Troubleshooting
Panel does not perform self-test
Possible Cause
Possible Remedy
Tripped overcurrent
protection
Correct fault, replace or reset overcurrent protection
Faulty connection to battery
Correct battery connections (see Battery Circuit Requirements above)
Panel performs normal self-test, engine cranks, runs and shuts down
Possible Cause
Possible Remedy
Only Battery LED illuminated
Correct battery charge failure (see Battery not charging above)
Only Oil Pressure LED
Illuminated
Correct low oil pressure condition or faulty switch, correct wiring fault
Only Temperature LED
Illuminated
Correct overheating condition or faulty switch, correct wiring fault
Only Aux LED Illuminated
Correct fault condition (i.e. v-belt, coolant level) or faulty switch, correct
wiring fault
All normally closed shutdowns
illuminate for one second
(panel reset)
Add suppressor diodes, protect from nearby lightning strikes, shield
induced spikes from other equipment, add electric motor control relay

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Testing Shutdown Inputs
Shutdown switches signal a fault by ground contact in most systems. Shutdown operation can be verified
by grounding the shutdown inputs individually. It may be necessary to remove the wire from the shutdown
switch to perform this test.
Note
Most shutdown switches are grounded through the switch body.
Do not use insulating sealant (i.e. Teflon tape) when installing switches.
Some thermostat housings are composites and do not provide ground for the switch.
Document Revision History
Rev A: 22-May-2006 Corrected typographical errors
Rev B: 26-Oct-2006 Add symbols to Indicators, corrected typographical errors
Rev C: 8-Jan-2007 Updated schematics, removed Power Box information
Rev C.1: 28-Feb-2007 Added part numbers
Rev D: 12-Jun-2013 Updated format, removed DPG references, updated schematics.

Typical Schematics
The following pages show typical schematics.
Details vary from installation to installation.
See the specific schematics for installation for details.