AEM Infinity 3 Series User manual

Infinity Series 3 Marine Adapter
MEFI4 30-3829
AEM Performance Electronics
AEM Performance Electronics, 2205 126th Street Unit A, Hawthorne, CA90250
Phone: [phone] Fax: [phone]
http://www.aemelectronics.com
Instruction Part Number: <%DOCNUMBER%>
Document Build 2/8/2021
Instruction
Manual
WARNING!
Improper installation and/or adjustment of this product can result in major engine/vehicle damage. For
technical assistance visit our dealer locator to find a professional installer/tuner near you.
Note: AEM holds no responsibility for any engine damage or personal injury that results from the misuse
of this product, including but not limited to injury or death.
STOP!
THIS PRODUCT HAS LEGAL RESTRICTIONS.
READ THIS BEFORE INSTALLING/USING!
WARNING! THIS IS A RACE ONLY PRODUCT MANUFACTURED AND SOLD FOR INSTALLATION ON VEHICLES DESIGNED TO BE USED
SOLELY FOR COMPETITION PURPOSES. ONCE THIS PART IS INSTALLED, THE VEHICLE MAY NEVER BE USED, OR REGISTERED
OR LICENSED FOR USE, ON A PUBLIC ROAD OR HIGHWAY. IF YOU INSTALL THIS PART ON YOUR VEHICLE AND USE THE VEHICLE
ON A PUBLIC ROAD OR HIGHWAY, YOU WILL VIOLATE THE CLEAN AIR ACTAND MAY BE SUBJECT TO PERSONAL CIVIL OR
CRIMINAL LIABILITY, INCLUDING FINES OF UP TO $4,819 PER DAY.
IT IS THE RESPONSIBILITY OF THE INSTALLER AND/OR USER OF THIS PRODUCT TO ENSURE THAT IT IS USED IN COMPLIANCE
WITH ALL APPLICABLE LAWS AND REGULATIONS. IF THIS PRODUCT WAS PURCHASED IN ERROR, DO NOT INSTALL AND/OR USE
IT. THE PURCHASER MUST ARRANGE TO RETURN THE PRODUCT FOR A FULL REFUND.
THIS POLICY ONLY APPLIES TO INSTALLERS AND/OR USERS WHO ARE LOCATED IN THE UNITED STATES; HOWEVER
CUSTOMERS WHO RESIDE IN OTHER COUNTRIES SHOULD ACT IN ACCORDANCE WITH THEIR LOCAL LAWS AND REGULATIONS.

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1Introduction
General Motors Powertrain introduced the Marine Electronic Fuel Injection (MEFI) system in 1992. The
fourth generation of the GM MEFI system is known as the MEFI-4 was introduced around 2004.
Double Click on the followingimage to open a copy of the original brochure.
The AEM30-3829 adapter harness is designed to adapt an Infinity Series 3 ECUto an existing MEFI-4
engine harness. The Infinity Series 3 ECU and 30-3829 adapter harness combination will not solve
existing problems. AEMrecommends checking your engine for existing diagnostic trouble codes before
installing the new AEM products. A basic list of diagnostic codes is shown below. More detailed
information can be found in the following manual. Double Click on the following image to open a
copy of the diagnostic manual.

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2Recommended Accessories
The Series 3 Infinity ECU does not have an onboard UEGO controller. The following products are
recommended for accurate lambda measurements and control.
30-0300 / X-Series Wideband UEGO AFR Sensor Controller Gauge
30-0310 / X-Series Inline Wideband UEGO AFR Controller
3ECU Connectors
The Infinity ECUs use the MX123 Sealed Connection System fromMolex. AEMstrongly recommends
that users become familiar with the proper tools and procedures before attempting any modifications or
additions to these connector housings. The entire Molex user manual can be downloaded direct from

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Molexat http://www.molex.com/mx_upload/family//MX123UserManual.pdf
4Harness Installation Tips
FOR AUTOMOTIVE APPLICATIONS OF MARINE MEFI HARNESS:
In order for cooling fans to function via Infinity Series 3 ECUcontrol, Pin J1-23 of the FACTORY
HARNESS must be moved to Pin J1-22. Please see pinout documentation for information regarding J1
connector.
Wiring Conventions and EMI
Some wire harness assemblies come pre-wired with all connectors, fuses, and relays needed to operate
an engine. Harnesses that include a PDC generally require extension/termination of the flying leads to
their appropriate devices, and additional sensors and other devices can be wired into the harness as
needed for the specific application. The following guidelines should be adhered to while completing the
required wiring.
A proper wiring job includes proper termination of the wire at the sensor. The wire terminal end must be
moisture tight where it plugs into the sensor and it must have strong, electrically sound terminals. The
preferred method of securing a wire to a terminal is to use a crimp terminal with NO solder. It is
important to use the proper crimping tool for sound terminal construction. Plastic terminal plugs must
have moisture tight seals. Inspect each plug to make sure the seals are in place. Di-electric grease can
be added in the terminal slots to further aid in corrosion resistance.
If a splice into a wire must be made and no solder-less terminals are available, then you must properly
solder the splice.
Noise can be a serious problem and can cause intermittent misfiring of the engine. Every precaution
should be taken to prevent interference to the ECU’s operation. Resistive plug leads are REQUIRED.
To eliminate or reduce the chance of EMI, wires that carry high current must run in twisted pairs. An
example of this would be the power leads froma multiple spark ignition system. These ignition systems
can carry up to 100 amps for a couple milliseconds at the time of discharge, which induces a strong
magnetic field in close proximity of the wires.
The routing of the wire loom is critical to EFI system performance and safety. The following safety
considerations should be made when installing the wire loom:
· Heat protection: the loomshould be placed away from or insulated from sources of heat. The
obvious item(s) that should be avoided are the exhaust manifolds, EGRdelivery tubes, and
turbochargers. If it is absolutely necessary to route a wire in close proximity to any of these
items, then a suitable insulator must be used. Reflective foil insulators should be used on all
harness lengths that are routed in close proximity to extreme sources of heat.
· Noise suppression: do not route wires near HT (High Tension) leads such as ignition wires from
a distributor or a CNP (Coil Near Plug) ignition system. For coil-on-plug ignition systems this is
not as critical.
· Shielding of important signal input wires such as Crank Sensor input, Cam Sensor input, and
Knock Sensor input should be addressed when assembling a harness. VR (Variable
Reluctance) sensors, also known as MAGsensors, are 2 wire sensors that generate a voltage
as the frequency increases of the trigger wheel. These wires MUSTbe wired in a twisted pair
configuration with a shield. The shield should be terminated to chassis ground at ONE END of
the lead while the other end is left unterminated. Failure to shield these wires with proper shield

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termination will result in noise on the signal and subsequent errors in the Infinity ECU. Hall
Sensors (3 Wire) are not as susceptible to noise, but care should be taken into account when
routing these wires.
· Moving component protection: route wires away from moving components such as fans, the
blower belt, or the throttle linkage. Also, make sure the wires are not under any strain when the
engine is at full deflection on the motor mounts. This may be hard to test, ensure that there is at
least a few inches of slack in harnessing between engine-mounted and chassis-mounted
components. The use of Zip Ties is an acceptable method of securing a harness frommoving
components.
· Never have the wires in exposed bundles throughout the engine compartment. All wires should
be covered in a protective sheathing, at minimum, plastic corrugated loomto protect harness
fromabrasion. Ideally, a harness should be covered in a fire-resistant sheathing rated to a
minimumof 125C, or 257F.
· When utilizing CANBus communication devices in the harness, it is important that the CAN
Hi/Lo wires are twisted at a minimum of 1 twist per inch. When terminating these wires, ensure
that there is a 120 ohm terminating resistor installed between the two CANwires at each end of
the CANBus. If a connected device has an internal CAN terminating resistor, no external
resistor is needed.
· All additional controlled devices wired into the vehicle need to be wired with appropriately sized
wiring. When considering wire size requirements, the following factors should be considered:
Amperage of device, length of wire, heat source near wire and component. Both positive and
ground circuits require equal attention to this detail and care should be taken to choose the
appropriate wire gauge. Always use a larger wire gauge if unsure of power requirements of
device.
· Ensure that ground loops are completed correctly in the vehicle including: engine to chassis,
chassis to battery, ECU to chassis, etc.
· Ensure that when installing any additional +12vcomponents, all power (+12v) leads should be
fused with an appropriately sized fuse. Ensure that the fuse selected does not exceed the
current carrying capacity of the wire used to control the component.
· Relays should be selected so that they are capable of carrying the load of the controlled device.
Ensure that the relay has enough current carrying capacity and that the fuse in the circuit does
not exceed the rating of relay. Failure to address this will result in the relay becoming the fuse,
rather than the fuse in the circuit.
Determining ECU Location
· It is recommended that the ECU be placed in an environment that does not expose it to
temperatures above 85° Celsius (160F).

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5Harness Installation
Disconnect the MEFI4 Harness fromthe MEFI controller. Remove the MEFI Controller.
Review of the MEFI engine harness.
J1 has a Black TPA as shown below.
J2 has a Clear TPA as shown below.

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Connect J1 with the AEMadapter harness with black wires.
Connect J2 with the AEMadapter harness with white wires.

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Connect the73 Pin connector to the Series 3 ECU.

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6Harness Layout
Connector
Installation
MEFI J1
Connect to MEFI J1 with BLACK TPA
MEFI J2
Connect to MEFI J2 with Clear TPA
AUX
Optional I/O features. See pinout.
AEMNet
Optional CAN
Flash
Enable
Optional - Sets ECU to flash mode
manually
EFI Relay
Power distribution relay
Lambda1
0-5V analog to ECU Analog 18 input
Lambda2
0-5V analog to ECU Analog 19 input
HEI
Distributor
HEI distributor interface. Default
setup for HEI. Remove and replace
with jumper for non-HEI setups

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7Harness Pinout
Infinity Connector C1
73 Way F Receptacle0.64 2.8 Series
Sealed (GY)
Pin
Wire
Color
Gauge
Destination
Function
Installer Notes
C1-1
WHT
20
J2-13
COIL 5
C1-2
WHT
20
J2-12
COIL 3
C1-3
BLK
20
J1-16
IAC 1A
C1-4
BLK
20
J1-30
IAC 2A
C1-5
BLK
20
J1-15
IAC 2B
C1-6
BLK
20
J1-15
IAC 1B
C1-7
BLK
20
R1
MAIN RELAYCONTROL
C1-8
C1-9
C1-10
C1-11
C1-12
WHT
22
C6-1
CAN HI
C1-13
GRN
22
C6-2
CAN LO
C1-14
WHT
20
J2-31
COIL 1
C1-15
WHT
20
J2-28
COIL 4
C1-16
WHT
20
J2-29
COIL 6
C1-17
WHT
20
J2-30
COIL 7
C1-18
WHT
20
J2-19
IGN SWITCH IN
C1-19
BLK
18
SP3-R
ECU+12V
C1-20
BLK
22
J1-1
KNOCK SENSOR 2
C1-21
BLK
22
J1-17
KNOCK SENSOR 1
C1-22
BLK
22
SP4-R
SIG GND (ANALOG SENSOR GROUND)
C1-23
BLK
22
C5-3
SIG GND (ANALOG SENSOR GROUND)
C1-24
WHT
22
J2-16
CRANKSHAFT POSITION SENSOR HALL
C1-25
WHT
22
J2-32
CAMSHAFTPOSITION SENSOR HALL
C1-26
WHT
22
J2-20
EXHAUST TEMP S/W
C1-27
BLK
22
C5-6
DIGITAL 3 (FLEX FUEL)
C1-28
C1-29
BLK
22
C5-9
DIGITAL 5 (CLUTCH SWITCH)
C1-30

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C1-31
C1-32
WHT
20
J2-15
COIL 8
C1-33
WHT
20
J2-14
COIL 2
C1-34
BLK
20
SP2-R
PERM BATTERYPWR
C1-35
BLK
18
SP3-R
RELAY POWER IN 12V
C1-36
BLK
22
C2-1
FLASH ENABLE
C1-37
WHT
22
J2-7
CLTTEMP
C1-38
WHT
22
J2-21
AIR TEMP
C1-39
BLK
22
C5-2
OILTEMP (ANALOG TEMP 3)
C1-40
WHT
22
J2-23
TPS
C1-41
WHT
22
J2-8
MAP
C1-42
BLK
22
J1-32
FUEL PRESS (ANALOG 9)
C1-43
BLK
22
C5-11
ANALOG 10
C1-44
WHT
22
J2-2
VCC (ANALOG SENSOR POWER +5V)
C1-45
BLK
22
C5-4
VCC (ANALOG SENSOR POWER +5V)
C1-46
BLK
22
C5-12
ANALOG 11
C1-47
BLK
22
C5-5
ANALOG 13
C1-48
BLK
22
J1-4
ANALOG 16
C1-49
BLK
20
C3-1
ANALOG 18 (LAMBDA 1)
C1-50
BLK
20
C4-1
ANALOG 19 (LAMBDA 2)
C1-51
BLK
18
SP1-R
BATTERYGROUND
C1-52
C1-53
BLK
22
J1-8
LOWSIDE9 (BUZZER)
C1-54
BLK
22
J1-9
LOWSIDE8 (ENGINETEMP LAMP)
C1-55
BLK
22
J1-23
LOWSIDE7 (EOP LAMP)
C1-56
BLK
22
J1-27
LOWSIDE6 (MILLAMP)
C1-57
WHT
22
C10-11
LOWSIDE5 (HEI BYPASS)
C1-58
C1-59
C1-60
C1-61
C1-62
BLK
18
J1-11
INJECTOR B (PEAK AND HOLD)
C1-63
BLK
18
J1-26
INJECTOR A (PEAK AND HOLD)
C1-64
C1-65

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C1-66
C1-67
C1-68
BLK
22
J1-14
LOWSIDE4 (TACH)
C1-69
C1-70
BLK
20
C5-10
LOWSIDE2
C1-71
BLK
20
C5-7
LOWSIDE 1
C1-72
BLK
18
J1-6
FUELPUMP (LOWSIDE 0)
C1-73
BLK
18
J1-13
BATTERYGROUND
DIAGRAM AS VIEWED FROM WIRE ENTRY SIDE!
MEFI J1
Pin
Wire
Color
Gauge
Destination
AEM
Function
MEFI
5.0/5.7L
MEFI
6.0/8.1L
Installer
Notes
J1-1
BLK
22
C1-20
KNOCK 2
KNOCK SENSOR 2
SIGNAL
J1-2
DIAGNOSTIC TEST
TERMINAL
DIAGNOSTIC TEST
TERMINAL
J1-3
J1-4
BLK
22
C1-48
ANALOG 16
GEN WARN2
INPUT
GEN WARN2
INPUT
J1-5
J1-6
BLK
18
C1-72
FUELPUMP RELAY
FUELPUMP
RELAY
FUELPUMP
RELAY
J1-7
J1-8
BLK
22
C1-53
LOWSIDE9
BUZZER
BUZZER
J1-9
BLK
22
C1-54
LOWSIDE8
CHECK GAUGES
LAMP
CHECK GAUGES
LAMP

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J1-10
J1-11
BLK
18
C1-62
FUEL INJECTOR B
FUEL INJECTOR B
FUEL INJECTOR B
J1-12
J1-13
BLK
18
C1-73
GROUND
ECM GROUND
ECM GROUND
J1-14
BLK
22
C1-68
TACH
TACH OUTPUT1
TACH OUTPUT1
J1-15
BLK
20
C1-5
IAC 2B
IAC COIL B LOW
IAC COIL B LOW
J1-16
BLK
20
C1-3
IAC 1A
IAC COILAHIGH
IAC COILAHIGH
J1-17
BLK
22
C1-21
KNOCK 1
KNOCK SENSOR 1
SIGNAL
KNOCK SENSOR 1
SIGNAL
J1-18
J1-19
J1-20
J1-21
J1-22
J1-23
BLK
22
C1-55
LOWSIDE7
GEN WARN2
LAMP
GEN WARN2
LAMP
J1-24
J1-25
J1-26
BLK
18
C1-63
INJECTOR A
INJECTOR A
INJECTOR A
J1-27
BLK
22
C1-56
LOWSIDE6
MALFUNCTION
INDICATOR LAMP
MALFUNCTION
INDICATOR LAMP
J1-28
BLK
18
SP1-L
GROUND
ECM GROUND
ECM GROUND
J1-29
BLK
18
SP1-L
GROUND
ECM GROUND
ECM GROUND
J1-30
BLK
20
C1-4
IAC 2A
IAC COILALOW
IAC COILALOW
J1-31
BLK
20
C1-6
IAC 1B
IAC COILB HIGH
IAC COILB HIGH
J1-32
BLK
22
C1-42
FUELPRESSURE
DIAGRAM AS VIEWED FROM WIRE ENTRY SIDE!

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MEFI J2
Pin
Wire
Color
Gauge
Destination
Function
MEFI
5.0/5.7L
MEFI
6.0/8.1L
Installer
Notes
J2-1
WHT
18
SP2-L
PERM +12V
BATTERYFEED
BATTERYFEED
J2-2
WHT
22
C1-44
VREF +5V
5 VOLT
REFERENCE
5 VOLT
REFERENCE
J2-3
WHT
22
SP4-L
SENSOR GROUND
SENSOR
GROUND
SENSOR
GROUND
J2-4
J2-5
J2-6
J2-7
WHT
22
C1-37
COOLANTTEMP
ECTSENSOR
SIGNAL
ECTSENSOR
SIGNAL
J2-8
WHT
22
C1-41
MANIFOLD
PRESSURE
MAP SENSOR
SIGNAL
MAP SENSOR
SIGNAL
J2-9
J2-10
SERIALDATA
SERIALDATA
J2-11
J2-12
WHT
20
C1-2
COIL 3
IGNITION
CONTROL H
J2-13
WHT
20
C1-1
COIL 5
IGNITION
CONTROL F
J2-14
WHT
20
C1-33
COIL 2
IGNITION
CONTROL D
J2-15
WHT
20
C1-32
COIL 8
IGNITION
CONTROL B
J2-16
WHT
22
C1-24
CRANK HALL
CRANK SENSOR
SIGNAL
CRANK SENSOR
SIGNAL
J2-17
WHT
22
SP3-L
VBATT +12V
DEPSPOWER
DEPSPOWER
J2-18
WHT
22
SP4-L
SENSOR GROUND
DEPSLO
DEPSLO
J2-19
WHT
20
C1-18
IGNITION SWITCH
IGNITION FEED
IGNITION FEED
J2-20
WHT
22
C1-26
DIGITAL 2
EXHAUSTTEMP
SWITCH INPUT
J2-21
WHT
22
C1-38
INLETAIR TEMP
IATSENSOR
SIGNAL
J2-22
J2-23
WHT
22
C1-40
THROTTLE
POSITION
TP SENSOR
SIGNAL
TP SENSOR
SIGNAL
J2-24
J2-25
J2-26
J2-27

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J2-28
WHT
20
C1-15
COIL 4
IGNITION
CONTROL G
J2-29
WHT
20
C1-16
COIL 6
IGNITION
CONTROL E
J2-30
WHT
20
C1-17
COIL 7
IGNITION
CONTROL C
J2-31
WHT
20
C1-14
COIL 1
IGNITION
CONTROL
IGNITION
CONTROL A
J2-32
WHT
22
C1-25
CAM HALL
CAM SENSOR
SIGNAL
CAM SENSOR
SIGNAL
DIAGRAM AS VIEWED FROM WIRE ENTRY SIDE!
C2 - FLASH ENABLE
Pin
Wire
Color
Gauge
Destination
Function
Installer Notes
C2-1
BLK
22
C1-36
FLASH ENABLE
C2-2
BLK
22
SP2-R
PERM +12V
DIAGRAM AS VIEWED FROM WIRE ENTRY SIDE!
C3 - LAMBDA 1
Pin
Wire
Color
Gauge
Destination
Function
Installer Notes

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C3-1
BLK
20
C1-49
LAMBDA 1
C3-2
BLK
20
SP4-L
SENSOR GROUND
C3-3
DIAGRAM AS VIEWED FROM WIRE ENTRY SIDE!
C4 - LAMBDA 2
Pin
Wire
Color
Gauge
Destination
Function
Installer Notes
C4-1
BLK
20
C1-50
LAMBDA 2
C4-2
BLK
20
SP4-L
SENSOR GROUND
C4-3
DIAGRAM AS VIEWED FROM WIRE ENTRY SIDE!
C5 - AUX
Pin
Wire
Color
Gauge
Destination
Function
Installer Notes
C5-1
BLK
22
SP6-L
FUELPRESSURE
C5-2
BLK
22
C1-39
ANALOG TEMP 3
C5-3
BLK
22
C1-23
SENSOR GROUND

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C5-4
BLK
22
C1-45
VREF +5V
C5-5
BLK
22
C1-47
ANALOG 13
C5-6
BLK
22
C1-27
DIGITAL 3
C5-7
BLK
20
C1-71
LOWSIDE1
C5-8
BLK
18
SP3-L
VBATT +12V
C5-9
BLK
22
C1-29
DIGITAL 5
C5-10
BLK
20
C1-70
LOWSIDE2
C5-11
BLK
22
C1-43
ANALOG 10
C5-12
BLK
22
C1-46
ANALOG 11
DIAGRAM AS VIEWED FROM WIRE ENTRY SIDE!
C6 - AEMNET
Pin
Wire
Color
Gauge
Destination
Function
Installer Notes
C6-1
WHT
22
C1-12
CAN HI
C6-2
GRN
22
C1-13
CAN LO
C6-3
RED
22
SP3-L
VBATT +12V
C6-4
BLK
22
SP1-L
GROUND

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DIAGRAM AS VIEWED FROM WIRE ENTRY SIDE!
R1 - MAIN EFI RELAY
Pin
Wire
Color
Gauge
Destination
Function
Installer Notes
30
BLK
18
SP2-L
PERM +12V
85
BLK
20
C1-7
MAIN RELAYCONTROL
86
BLK
20
SP2-L
PERM +12V
87
BLK
18
SP3-L
ECU+12V
87A
DIAGRAM AS VIEWED FROM WIRE ENTRY SIDE!