Infiniti M45 (Y34). Manual - part 458

DTC P1220 FUEL PUMP CONTROL MODULE (FPCM)

EC-521

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Wiring Diagram

ABS002PW

TBWA0306E

EC-522

DTC P1220 FUEL PUMP CONTROL MODULE (FPCM)

Specification data are reference values and are measured between each terminal and ground.

CAUTION:

Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.

Diagnostic Procedure

ABS002PX

1. 

CHECK GROUND CONNECTIONS

1.

Turn ignition switch OFF.

2.

Loosen and retighten two ground screws. 
Refer to 

EC-141, "Ground Inspection"

 .

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace ground connections.

TER-

MINAL 

NO.

WIRE 

COLOR

ITEM

CONDITION

DATA (DC Voltage)

25

B/R

Fuel pump control 
module (FPCM)

[When cranking engine]

0 - 0.5V

[Engine is running]

●

Warm-up condition

●

Idle speed

8 - 12V

41

GY

Fuel pump relay

[Ignition switch: ON]

●

For a few seconds after turning ignition switch 
ON

[Engine is running]

0 - 1.0V

[Ignition switch: ON]

●

More than a few seconds after turning ignition 
switch ON.

BATTERY VOLTAGE
(11 - 14V)

116

G/R

Fuel pump control 
module (FPCM) check

[Engine is running]

●

More than a few seconds after turning ignition 
switch ON

Approximately 0V

[Ignition switch ON]

●

For a few seconds after turning ignition switch 
ON

[Engine is running]

●

Warm-up condition

●

Idle speed

4 - 6V

PBIB1118E

DTC P1220 FUEL PUMP CONTROL MODULE (FPCM)

EC-523

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2. 

CHECK FPCM POWER SUPPLY CIRCUIT

1.

Disconnect fuel pump control module (FPCM) harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between FPCM terminal 2 and ground with CON-
SULT-II or tester.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 3.

3. 

DETECT MALFUNCTIONING PART

Check the following.

●

Harness connectors M141, B211

●

Harness connectors B62, B262

●

Harness for open or short between FPCM and harness connector B211

>> Repair open circuit or short to ground or short to power in harness or connectors.

4. 

CHECK FPCM GROUND CIRCUIT-I FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Check harness continuity between FPCM terminal 3 and ground.
Refer to Wiring Diagram.

3.

Also check harness for short to power.

OK or NG

OK

>> GO TO 5.

NG

>> Repair open circuit or short to power in harness or connectors.

Voltage: Battery voltage

PBIB1129E

PBIB0099E

Continuity should exist.

EC-524

DTC P1220 FUEL PUMP CONTROL MODULE (FPCM)

5. 

CHECK FPCM GROUND CIRCUIT-II FOR OPEN AND SHORT

1.

Disconnect “fuel level sensor unit and fuel pump” harness con-
nector.

2.

Disconnect dropping resistor harness connector.

3.

Check harness continuity between the following;
“fuel level sensor unit and fuel pump” terminal 1 and dropping
resistor terminal 2, 
FPCM terminal 4 and dropping resister terminal 2.
Refer to Wiring Diagram.

4.

Check harness continuity between the following;
FPCM terminal 4 and ground, 
“fuel level sensor and fuel pump” terminal 1 and ground.
Refer to Wiring Diagram.

5.

Also check harness for short to power.

OK or NG

OK

>> GO TO 7.

NG

>> GO TO 6.

6. 

DETECT MALFUNCTIONING PART

Check the following.

●

Harness connectors B62, B262

●

Harness for open or short between “fuel level sensor unit and fuel pump” and dropping resistor

●

Harness for open or short between FPCM and dropping resistor

●

Harness for open or short between “fuel level sensor unit and fuel pump” and ground

●

Harness for open or short between FPCM and ground

>> Repair open circuit or short to ground or short to power in harness or connectors.

7. 

CHECK FPCM INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Disconnect ECM harness connector.

2.

Check harness continuity between ECM terminal 116 and FPCM terminal 4.
Refer to Wiring Diagram.

3.

Check harness continuity between ECM terminal 116 and ground.
Refer to Wiring Diagram.

4.

Also check harness for short to power.

OK or NG

OK

>> GO TO 9.

NG

>> GO TO 8.

Continuity should exist.

Continuity should not exist.

PBIB1127E

Continuity should exist.

Continuity should not exist.