Hyundai Ioniq HEV 2017 User manual

Hybrid Control System
Safety Precaution
Precautions to take before servicing high voltage system
• Since hybrid vehicles contain a high voltage battery, if the high voltage system or vehicles are handled incorrectly, this might lead to
a serious accidents like electric shock and electric leakage.
• Be sure to shut off the high voltage by removing the safety plug before performing inspection or repairing the high voltage system.
(Refer to "High Voltage Shut-off Procedures")
• The responsible worker keeps the removed safety plug to prevent the plug from being connected by mistake.
• Do not keep any metal objects (watch, ring etc.) while working on the high voltage system, which it can cause serious accidents like
electric shock.
• Before beginning work on the high voltage system, the worker should wear personal protective equipment to prevent safety
accidents.
(Refer to "Personal Protective Equipment")
• Never allow workers who are not wear personal protective equipment to touch the high voltage system. High voltage components
should be covered with an insulation sheet to prevent safety accidents.
• Use insulation tools when working on the high voltage system.
• Put the removed high voltage components on the insulation mat.
• All the high voltage wiring and connectors are orange.
• A caution label for high voltage is attached to the high voltage components.
• High voltage components :
High Voltage Battery Pack Assembly, Power Relay Assembly (PRA), BMS ECU, Hybrid Power Control Unit (HPCU), Hybrid Drive
Motor, HSG, Electric A/C Compressor, Low DC/DC Converter (LDC), Power Cable, Electric Compressor etc.
• Inform of danger of high voltage by putting the "high voltage caution" on the vehicle as image below.
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Personal Protective Equipment
Name Illustration Description
Insulation glove
Used when inspecting or working on the high voltage
components
[Insulation performance : 1000V / 300A or above]
Insulation shoes
Used when inspecting or working on the high voltage
components
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Insulation clothes
Insulation helmet
Safety glasses
Used in the case below
• During Removal & installation or inspection of the high
voltage battery terminals or wiring, which spark might
happen.
• During working on the high voltage battery pack
assembly.
Face shield
Insulation mat Putting the removed high voltage components on the
insulation mat to prevent safety accidents.
Insulation sheet
Covering the high voltage components with insulation
sheet to prevent people who don’t wear the personal
protective equipment from safety accidents.
Precautions to take when handling power cable
• Immediately insulate the high voltage terminal after reconnecting the terminal (use insulation tape).
• Tighten the high voltage terminal screw to spec torque.
• Be careful that (+) and (-) terminals do not come in contact when connecting or disconnecting power cable and busbar.
Precautions to take when handling high voltage battery
• When transporting high voltage battery, be sure to keep it flat and leveled. Failure to do so may decrease the battery performance and/or its
life-span.
• High voltage battery''s performance may decrease if it is exposed to high temperature for a lengthy period. As a result, heat-treatment after
painting must not exceed 70°C/ 30 minutes, or 80°C/ 20 minutes.
Precautions in case of fire on high voltage battery system
• If the fire occurs indoor, ventilate the area to let out hydrogen gas.
• ACB fire extinguisher is recommended for putting out the fire. (water may also be used).
Precautions in case of high voltage battery gas or electrolyte leakage
•
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Hybrid Control System
Turn OFF the Start button. Keep the Smart Key at least 2 meters away from the vehicle to prevent unintended engine start.
• Gas is hydrogen and alkaline vapor. If the leakage is indoor, ventilate the area immediately and evacuate to a safe location.
• If the leaked liquid comes in contact with skin, immediately neutralize the affected area with boric acid solution, then clean with tap water or
saline solution.
• If the leaked vapor or liquid gets in the eye, immediately clean the affected eye with water then get medical attention.
• If the gas leakage is caused by high temperature, then do NOT use the battery until the high voltage battery fully cools down to room
temperature.
Precautions when handling the vehicle after an accident
• Be sure to wear insulated gloves (or rubber gloves), protective goggles, insulated suite, and insulated boots.
• Do NOT touch bare cable under any condition.
(Refer to "Precautions when handling power cable")
• In case of vehicle fire, put out the fire with ABC extinguisher. Do NOT use water (usage of large volume of water is okay, but small volume
can worsen the situation).
• If more than half of the vehicle is submerged, then do NOT go near the Safety Switch or other high voltage related components. If such a
component must be accessed, then move the vehicle to the safe location first before handling the component.
• Gas is hydrogen and alkaline vapor. If the leakage is indoor, ventilate the area immediately and evacuate to a safe location.
• If the leaked liquid comes in contact with skin, immediately neutralize the affected area with boric acid solution, then clean with tap water or
saline solution.
• Refer to "High voltage cut-off procedure" if the high voltage needs to be cut off.
Preparations when servicing the accident vehicle
• Be sure to wear insulated gloves (or rubber gloves), protective goggles, insulated suite, and insulated boots.
• Boric Acid Power or Solution
• ABC Extinguisher
• Towel for cleaning electrolyte
• Vinyl tape (for insulating terminal)
• Mega ohm tester (for checking high voltage)
Precautions in case HEV is left unattended for a lengthy period
• Turn OFF the Start button. Keep the Smart Key at least 2 meters away from the vehicle to prevent unintended engine start.
• We recommend that HEV is driven at least 1 time for over 30 minutes every 2 months to protect and manage the high voltage battery
(inquire at relevant team in HMC).
• When inspecting or exchanging the auxiliary battery, check high voltage battery SOC reset related problems.
Hybrid Vehicle Refrigerant Recovery / Charging Precautions
• Since the electric compressor uses high-voltage, you should use POE oil which have high Volumetric Resistivity.
• Do not use the same A/C recovery / charging station as conventional belt-driven compressors.
• If the POE oil of the system gets mixed with PAG oil, then dielectric breakdown due to decreased volumetric Resistivity can occur
and inoperative A/C compressor may result, A/C compressor may not work
High Voltage Shut-off Procedures
• Be sure to read and follow the "General Safety Information and Caution" before doing any work related with the high voltage system.
Failure to follow the safety instructions may result in serious electrical injuries.
• Be sure to read and follow the "High Voltage Shut-off Procedures" before doing any work related with the high voltage system.
Failure to follow the safety instructions may result in serious electrical injuries.
• High voltage components :
High Voltage Battery Pack Assembly, Power Relay Assembly (PRA), BMS ECU, Hybrid Power Control Unit (HPCU), Hybrid Drive
Motor, HSG, Electric A/C Compressor, Low DC/DC Converter (LDC), Power Cable, Electric Compressor etc.
1. Turn the ignition switch OFF and disconnect the auxiliary 12V battery negative (-) terminal.
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2. Remove the safety plug cover (A).
3. Unfasten the hook (A) and then remove the safety plug (C) by pulling the lever (B) to the direction of arrow.
4. Wait for more than 5 minutes so that the capacitor in the high voltage system can be fully discharged.
5. Measure the voltage between the inverter terminals to check that the capacitor in the inverter is discharged completely.
(1) Remove air cleaner assembly and air duct.
(Refer to Engine Mechanical System - "Air Cleaner")
(2) Disconnect the inverter power cable (A).
• Disconnect the inverter power cable as the procedures below.
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Hybrid Control System
(3) Measure the voltage between the inverter (+) terminal and the inverter (-) terminal.
Less than 30V : High voltage circuit properly shut
More than 30V : Fault on high voltage circuit
• If measured more than 30V, check if the safety plug is removed completely.If measured more than 30V despite the safety plug
is removed, there can be serious problems on the high voltage circuit. In this case, check DTC and never touch the high
voltage system circuits.
High voltage battery system inspection guide
• Be sure to read and follow the “General Safety Information and Caution” before doing any work related with the high voltage system.
Failure to follow the safety instructions may result in serious electrical injuries.
1. Carry out a visual inspection to determine whether the vehicle requires general repair or accident repair.
2. For the general repair, perform the repair based on the repair process for that DTC code.
3. For the car accident repair, determine the accident type before repair.
1) Electrical Accidents
– Over-charge/discharge: Displays a battery over voltage (P1B71) code /low voltage (P1B70) code (Refer to the DTC diagnosis guide).
– Short: Displays a high voltage short (P1B77, P1B25) codes (Refer to the DTC diagnosis guide).
2) Fire
Classification Inspection process Inspection results Measures
Fire outside of the high
voltage battery mount
※Example)
Engine fire
1. Perform visual inspections (deformation,
corrosion, wire coating, odor, connector).
2. Check for main fuse open circuit after
shutting off the high voltage.
3. Check the high voltage main relay for signs
of welding.
4. Measure the high voltage battery/chassis
insulation resistance.
5. Check other parts for failure.
6. Check the DTC code in the BMS ECU.
High voltage battery insulation
damaged
Remove the high voltage battery
and repair the insulation
process/coating.
High voltage
battery not
damaged
DTC code If a DTC code occurs, comply
with DTC diagnosis guide and
repair process.
No DTC code and
battery appears
normal
Do not replace the high voltage
battery (if the battery is damaged
and must be disposed of,
perform the high voltage battery
disposal process).
Fire in the high voltage
battery mount
1. Perform visual inspections (deformation,
corrosion, wire coating, odor, connector).
High voltage battery appears
damaged (heat, soot, etc.)
Remove the service disconnect
plug and perform the salt water
battery disposal process.
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※Example)
Trunk fire
2. Check for visible damage of the high
voltage battery.
3. Check the high voltage main relay for signs
of welding after shutting off the high voltage
if no visible damage is found in the high
voltage battery.
4. Measure the high voltage battery/chassis
insulation resistance.
5. Check other parts for failure.
6. Check the DTC code in the BMS ECU.
High voltage battery insulation
damaged
Remove the high voltage battery
and repair the coating/insulation.
High voltage
battery not
damaged
DTC code If a DTC code occurs, perform
the repair process outlined in the
DTC diagnosis guide.
No DTC code and
battery appears
normal
Do not replace the high voltage
battery (if the battery is damaged
and must be disposed of,
perform the high voltage battery
disposal process).
3) Collision
Classification Inspection process Inspection results Measures
Collision damage to
areas other than the
high voltage battery
mount
※Example)
Front/side collision
1. Perform visual inspections (deformation,
corrosion, wire coating, odor, connector).
2. Check for main fuse open circuit after
shutting off the high voltage.
3. Check the high voltage main relay for signs
of melting.
4. Measure the high voltage battery/chassis
insulation resistance.
5. Check other components.
6. Check the DTC code in the BMS ECU.
High voltage battery insulation
damaged
Remove the high voltage battery
and repair the coating/insulation.
High voltage
battery not
damaged
DTC code If a DTC code occurs, perform
the repair process outlined in the
DTC diagnosis guide.
No DTC code and
battery appears
normal
Do not replace the high voltage
battery (if the battery is damaged
and must be disposed of,
perform the high voltage battery
disposal process).
Collisions involving the
high voltage battery
mount
※Example)
Rear-end collision
1. Perform visual inspections (deformation,
corrosion, wire coating, odor, connector).
2. Check for main fuse open circuit after
shutting off the high voltage.
3. Check the high voltage main relay for signs
of melting.
4. Measure the high voltage battery/chassis
insulation resistance.
5. Check other components.
6. Check the DTC code in the BMS ECU.
High voltage battery insulation
damaged
⇑ Follow the measures outlined
above.
※ If the high voltage battery
mount is inaccessible due to
trunk or door damage, bend or
cut the exterior panels without
damaging the high voltage
system and carry out the
inspection and repair process.
High voltage
battery not
damaged
DTC code
No DTC code and
battery appears
normal
4) Submersion
Classification Inspection process Inspection results Measures
High voltage battery not
submerged
1. Perform a visual inspection (deformation,
corrosion, wire coating, odor, connector).
2. Check for main fuse open circuit after
shutting off the high voltage.
3. Check the high voltage main relay for signs
of melting.
4. Measure the high voltage battery/chassis
insulation resistance.
5. Check other components.
6. Check the DTC code in the BMS ECU.
High voltage battery insulation
damaged
Remove the high voltage battery
and repair the coating/insulation.
High voltage
battery not
damaged
DTC code If a DTC code occurs, perform
the repair process outlined in the
DTC diagnosis guide.
No DTC code and
battery appears
normal
Do not replace the high voltage
battery (if the battery is damaged
and must be disposed of,
perform the high voltage battery
disposal process).
High voltage battery
submerged
[Regardless of water
conditions]
1. Check for main fuse open circuit after
shutting off the high voltage.
2. Check the high voltage main relay for signs
of melting.
3. Measure the high voltage battery/chassis
insulation resistance.
4. Check the DTC code in the BMS ECU.
Carry out these measures regardless
of the inspection results
Remove the high voltage battery
and repair the coating/insulation.
Main Fuse Inspection
1. Remove the safety plug lever (A).
2. Remove the safety plug cover (A) and then remove the main fuse (B) by removing the mounting bolts.
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3. Measure the resistance of main fuse.
Specification:1 Ω or less Ω [20°C(68°F]
4. If the measured resistance is not within the specification, replace the main fuse.
Checking for Welding in the High Voltage Main Relay
In order to safely remove the battery pack assembly, you must first inspect the high voltage main relay for signs of weld damage.
You can use Gloval Diagnostic System (GDS) service data to detect weld damage in the high voltage main relay.
[Using GDS service data to check for main relay weld damage]
1. Connect the GDS to the self-diagnosis connector (DLC).
2. Turn on the ignition.
3. Check the BMS weld damage state in the GDS service data.
[Using a Multimeter to measure weld damage]
• Be sure to read and follow the "General Safety Information and Caution" before doing any work related with the high voltage system.
Failure to follow the safety instructions may result in serious electrical injuries.
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1. Shut off the high voltage.
(Refer to "High voltage Shut-off Procedures").
2. Remove the rear seat cushion.
(Refer to Body - "Rear Seat Assembly")
3. Remove the rear door scuff trim.
(Refer to Body - "Door Scuff Trim")
4. Remove the inlet duct.
(Refer to Hybrid Control System - "Cooling Duct")
5. Remove the high voltage battery rear cover.
(Refer to High Voltage Battery System - "Case")
6. Disconnect the high voltage (-) connector (A) and high voltage (+) connector (B).
7. Measure the high voltage main relay resistance and check for signs of weld damage.
Specification:∞ Ω [20°C (68°F)]
Isolation Resistance Inpection
The high voltage isolation used in hybrid systems can be checked using GDS service data or by measuring it directly.
[Using GDS service data to check isolation resistance]
1. Connect the GDS to the self-diagnosis connector (DLC).
2. Turn on the ignition.
3. Check the isolation resistance in the GDS service data.
Normal insulation resistance range:Around 1.0 MΩ
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[Measuring isolation resistance using an insulation tester (MΩ tester)]
• Be sure to read and follow the "General Safety Information and Caution" before doing any work related with the high voltage system.
Failure to follow the safety instructions may result in serious electrical injuries.
1. Shut off the high voltage circuit.
(Refer to Hybrid Control System - "High Voltage Shut-off Procedures")
2. Remove the rear seat cushion.
(Refer to Body - "Rear Seat Assembly")
3. Remove the rear door scuff trim.
(Refer to Body - "Door Scuff Trim")
4. Remove the inlet cooling duct.
(Refer to High Voltage Battery Cooling System - "Cooling Duct")
5. Remove the high voltage battery rear cover.
(Refer to High Voltage Battery System - "Case")
6. Connect the insulation tester (-) terminal (A) to the battery system case (or ground).
7. Connect the insulation tester (+) terminal to the high voltage battery (+) and (-). Measure the resistance.
[Measure the isolation resistance on the power relay assembly high voltage power terminal (+)]
(1) Connect the insulation tester (+) terminal to the (+) PRA high voltage power terminal (A).
(2) Supply 500V through the insulation tester and wait one minute to measure the stable resistance.
(3) Check the isolation resistance.
Normal insulation resistance range :Above 1.0 MΩ [20°C (68°F)]
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[Measure the isolation resistance on the power relay assembly high voltage power terminal (-)]
(1) Connect the insulation tester (+) terminal to the (-) PRA high voltage power terminal (B).
(2) Supply 500V through the insulation tester and wait one minute to measure the stable resistance.
(3) Check the isolation resistance.
Normal insulation resistance range :Above 1.0 MΩ [20°C (68°F)]
[Measure the isolation resistance on the power relay assembly inverter power terminal (+)]
• When measuring the insulated resistance on each PRA inverter, use a contact pin to prevent damage on the connector and for
more accurate measurement.
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(1) Connect the insulation tester (+) terminal to the (+) PRA inverter power terminal (A).
(2) Supply 500V through the insulation tester and wait one minute to measure the stable resistance.
(3) Check the isolation resistance.
Normal insulation resistance range : Above 1.0 MΩ [20°C (68°F)]
[Measure the isolation resistance on the power relay assembly inverter power terminal (-)]
• When measuring the insulated resistance on each PRA inverter, use a contact pin to prevent damage on the connector and for
more accurate measurement.
(1) Connect the insulation tester (+) terminal to the (-) PRA inverter power terminal (B).
(2) Supply 500V through the insulation tester and wait one minute to measure the stable resistance.
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(3) Check the isolation resistance.
Normal insulation resistance range :Above 1.0 MΩ [20°C (68°F)]
Handling Guide for Storing, Transporting, and Disposing of High Voltage Battery Systems
1. High voltage battery system handling process
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2. Defective high voltage battery system handling / Inspection
Classification Item Measures
Undamaged Battery
Storage Remove the service disconnect and store the battery under the same conditions as a new battery.
Transport Minimize impacts and ensure the battery does not come in contact with other parts.
Disposal Transport the battery to the designated disposer
Damaged
battery
Common Inspection
method
1. Voltage check(using a digital multimeter)
(1) Measure the voltage between the service disconnect plug upper (+) terminal and [High voltage
battery – PRA] connecting cable (-) terminal.
→ Specification: About 150 V
(2) Measure the voltage between the service disconnect plug lower (-) terminal and [High voltage
battery – PRA] connecting cable (+) terminal.
→ Specification: About 120 V
▶ Measures: If abnormal, submerse the battery in salt water immediately to prevent fire.
2. Temperature check(using a non-contact thermometer)
(1) Check the temperature of battery case.
(2) Check for temperature changes by measuring the temperature again after 30 minutes.
▶ Criteria: The change should be 3 °C or less and the temperature should be below 35 °C.
▶ Measures
– If the temperature is higher than 35°C, place the battery in a cool, dry place and wait for the
battery temperature to return to 35°C.
– If the temperature change is more than 3°C and it continues to rise, submerse the battery in
salt water immediately.
–
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If the temperature continues to rise when measuring it at 30 minute intervals, submerse the
battery in salt water immediately.
3. Isolation resistance check(using a MΩ tester)
(1) Measure the isolation resistance between the power relay terminal (+) and the battery pack
cover.
(2) Measure the isolation resistance between the power relay terminal (-) and the battery pack
cover.
▶ Criteria: 5MΩ or less (at 500V)
▶ Measures: Insulate the battery using insulating materials.
(Refer to "Take insulation actions for parts that may short circuit.)
4. Take insulation actions for parts that may short circuit(Visual inspection)
(1) High voltage battery – PRA cable terminal
(2) BMS voltage sensing connector
▶ Insulation actions
– Use the insulation tape or rubber cap to prevent short circuit to the battery pack, cells, modules.
– Fix the connector terminal to prevent wiring from moving.
5. Electrolyte leakage check
– Check for odors within 30cm of the battery pack (electrolyte odors like chemicals or acryl).
▶ Measures: Submerse the battery in salt water immediately if a smell is detected.
Damaged
battery
Damaged
battery check
results:
normal
Storage Remove the service disconnect plug and store the battery under the same conditions as a new
battery.
Transport Minimize impacts and ensure the battery does not come in contact with other parts.
Disposal Transport the battery to the designated disposer; discharge it by submersing it completely in salt water
and carry out the disposal procedure.
Damaged
battery check
results:
abnormal
Storage
Remove the service disconnect plug; insulate all exposed terminals; place the battery in a cool, dry
place away from volatile or combustible substances; use insulating materials (insulation tape, rubber
caps, etc.) or vinyl to wrap the battery; use anti-shock materials inside the box.
▶ Insulation action: Refer to "Take insulation actions for parts that may short circuit.
▶ Packing: Abnormal battery must be packed as same as a new battery.
Transport Minimize impacts and ensure the battery does not come in contact with other parts.
Disposal Transport the battery to the designated disposer; discharge it by submersing it completely in salt water
and carry out the disposal procedure.
Voltage Check
• Be sure to read and follow the “General Safety Information and Caution” before doing any work related with the high voltage system.
Failure to follow the safety instructions may result in serious electrical injuries.
1. Measure the voltage between the service disconnect plug upper (+) terminal and [High voltage battery –PRA] connecting cable (-) terminal.
→ Specification: About 150 V
2. Measure the voltage between the service disconnect plug lower (-) terminal and [High voltage battery –PRA] connecting cable (+) terminal.
→ Specification: About 120 V
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Take insulation actions for parts that may short circuit
1. High voltage battery – PRA cable terminal
– Place the insulation tape or rubber cap around the (+), (-) cable terminal to prevent short circuit to the battery pack.
– Secure the cable to the battery pack case with the insulation tape to prevent cables from moving.
2. BMS voltage sensing connector
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▶ Insulation actions
– Place the insulation tape or rubber cap around connectors to prevent short circuit to the battery cells, modules.
– Secure the wiring to the battery pack case with the insulation tape to prevent wiring from moving.
Discharging high voltage batteries
• Be sure to read and follow the “General Safety Information and Caution” before doing any work related with the high voltage system.
Failure to follow the safety instructions may result in serious electrical injuries.
High voltage batteries can cause electric shocks or other injuries. If the following symptoms are detected in a high voltage battery, discharge it
as soon as possible by submersing it in salt water.
– There are traces of fire or smoke.
– The voltage of the battery is abnormally high (302 V or higher).
– The temperature of the high voltage battery continues to rises abnormally.
– It smells like chemicals or acryl, which suggests electrolyte leakage.
[Discharging a battery by submersing it in salt water]
1. Pour about 53 gallons (200 liters) water into a plastic container (Ex. Poly Propylene) that cans submerge the whole battery.
2. Add 238 pounds of salt to the water. Stir the water until the salt dissolves into the solution.
• [The amount of salt] = 0.538 * [The amount of water that a battery can be fully immersed]
3. Use a lift jack to submerge the high voltage battery in the salt water.
4. Leave the battery in the salt water for 12 hours before taking it out a drying it thoroughly.
• The battery should be dried in a ventilated shade to avoid direct sunlight, snow and rain.
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Hybrid Control System
Hybrid Control System
• Put only one high voltage battery in a single salt water tank.
• If you discharge more than one battery, put in the battery after discharging the previous battery completely to ensure safety.
• If not, unexpected accidents such as burns may occur by exothermic reaction.
Procedure for entering engine forced activation mode
If the engine needs to be running constantly while the vehicle is stopped to inspect emission gas or perform maintenance on the vehicle, follow
below procedure to enter engine forced activation mode.
1. Place the shift lever in P range while the vehicle is stopped. Engage the parking brake. Then follow below procedure and enter engine
forced activation mode.
• Below procedure [(1) - (5)] for engine forced activation mode must be completed within 60 sec. In case the procedure is not
completed within the time, the process is reset and you must start again from step (1).
(1) Do NOT press on the brake pedal and press the Engine Start/Stop button 2 times to enter IG ON mode.
(2) Place the shift lever in P range and then press the accel pedal 2 times.
(3) Place the shift lever in N range and then press the accel pedal 2 times.
(4) Place the shift lever in P range and then press the accel pedal 2 times.
(5) Press on the brake pedal and press the Engine Start/Stop button to start the engine, and maintain idling.
• Engine will continue to remain idling and engine forced activation mode is maintained even if the gear is shifted to different range.
2. "READY" lamp blinks in the Cluster when the vehicle is in engine forced activation mode. Check that the "READY" lamp is blinking to ensure
that engine forced activation mode is entered correctly.
• "READY" lamp will continue to blink until engine forced activation mode is cancelled. "READY" lamp will stop blinking when the
forced activation mode is cancelled.
3. Engine forced activation mode can be cancelled by pressing the Engine Start/Stop button and switching to IG OFF mode.
Basic Troubleshooting
Basic Inspection Procedure
Measuring Condition of Electronic Parts'' Resistance
The measured resistance at high temperature after vehicle running may be high or low. So all resistance must be measured at ambient
temperature (20°C, 68°F), unless stated otherwise.
• The measured resistance in except for ambient temperature (20°C, 68°F) is reference value.
Intermittent Problem Inspection Procedure
Sometimes the most difficult case in troubleshooting is when a problem symptom occurs but does not occur again during testing. An example
would be if a problem appears only when the vehicle is cold but has not appeared when warm. In this case, the technician should thoroughly
make out a "Customer Problem Analysis Sheet" and recreate (simulate) the environment and condition which occurred when the vehicle was
having the issue.
1. Clear Diagnostic Trouble Code (DTC).
2. Inspect connector connection, and check terminal for poor connections, loose wires, bent, broken or corroded pins, and then verify that the
connectors are always securely fastened.
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3. Slightly shake the connector and wiring harness vertically and horizontally.
4. Repair or replace the component that has a problem.
5. Verify that the problem has disappeared with the road test.
● Simulating Vibration
a. Sensors and Actuators
: Slightly vibrate sensors, actuators or relays with finger.
• Strong vibration may break sensors, actuators or relays
b. Connectors and Harness
: Lightly shake the connector and wiring harness vertically and then horizontally.
● Simulating Heat
a. Heat components suspected of causing the malfunction with a hair dryer or other heat source.
• DO NOT heat components to the point where they may be damaged.
• DO NOT heat the ECM directly.
● Simulating Water Sprinkling
a. Sprinkle water onto vehicle to simulate a rainy day or a high humidity condition.
• DO NOT sprinkle water directly into the engine compartment or electronic components.
● Simulating Electrical Load
a. Turn on all electrical systems to simulate excessive electrical loads (Radios, fans, lights, rear window defogger, etc.).
Connector Inspection Procedure
1. Handling of Connector
a. Never pull on the wiring harness when disconnecting connectors.
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b. When removing the connector with a lock, press or pull locking lever.
c. Listen for a click when locking connectors. This sound indicates that they are securely locked.
d. When a tester is used to check for continuity, or to measure voltage, always insert tester probe from wire harness side.
e. Check waterproof connector terminals from the connector side. Waterproof connectors cannot be accessed from harness side.
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