Nissan Frontier D40. Manual - part 349

POWER SUPPLY AND GROUND CIRCUIT

EC-87

< COMPONENT DIAGNOSIS >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

POWER SUPPLY AND GROUND CIRCUIT

Diagnosis Procedure

INFOID:0000000005273048

1.

INSPECTION START

Start engine.
Is engine running?

Yes or No

Yes

>> GO TO 8.

No

>> GO TO 2.

2.

CHECK ECM POWER SUPPLY CIRCUIT-I

1.

Turn ignition switch OFF and then ON.

2.

Check voltage between ECM terminal 109 and ground with
CONSULT-III or tester.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.
• Fuse block (J/B) connector M4
• 10A fuse (No.1)
• Harness connectors M31, E152
• Harness for open or short between ECM and fuse

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

4.

CHECK GROUND CONNECTIONS

1.

Turn ignition switch OFF.

2.

Loosen and retighten two ground screws on the body. Refer to 

EC-90, "Ground Inspection"

.

OK or NG

OK

>> GO TO 5.

NG

>> Repair or replace ground connections.

5.

CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I

1.

Disconnect ECM harness connector.

2.

Check harness continuity between ECM terminals 1, 115, 116 and ground.
Refer to Wiring Diagram.

Voltage: Battery voltage

MBIB0015E

BBIA0614E

Continuity should exist.

EC-88

< COMPONENT DIAGNOSIS >

[QR25DE]

POWER SUPPLY AND GROUND CIRCUIT

3.

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 F32, E2
• Harness for open or short between ECM and ground

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

7.

CHECK ECM POWER SUPPLY CIRCUIT-II

1.

Reconnect ECM harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between IPDM E/R connector E119 terminal 3
and ground with CONSULT-III or tester.

OK or NG

OK

>> Go to 

EC-382

.

NG

>> GO TO 8.

8.

CHECK ECM POWER SUPPLY CIRCUIT-III

1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON and then OFF.

3.

Check voltage between ECM terminals 119, 120 and ground
with CONSULT-III or tester.

OK or NG

OK

>> GO TO 13.

NG (Battery voltage does not exist.)>>GO TO 9.
NG (Battery voltage exists for more than a few seconds.)>>GO  TO

11.

9.

CHECK ECM POWER SUPPLY CIRCUIT-IV

1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Check voltage between ECM terminal 111 and ground with
CONSULT-III or tester.

OK or NG

OK

>> GO TO 10.

NG

>> GO TO 11.

10.

CHECK ECM POWER SUPPLY CIRCUIT-V

1.

Disconnect ECM harness connector.

Voltage: Battery voltage

PBIB2658E

Voltage:

After turning ignition switch OFF, battery 
voltage will exist for a few seconds, then drop 
to approximately 0V.

PBIB1630E

Voltage: Battery voltage

PBIB1191E

POWER SUPPLY AND GROUND CIRCUIT

EC-89

< COMPONENT DIAGNOSIS >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

2.

Disconnect IPDM E/R harness connector E119.

3.

Check harness continuity between ECM terminals 119, 120 and IPDM E/R terminal 4.
Refer to Wiring Diagram.

4.

Also check harness for short to ground and short to power.

OK or NG

OK

>> GO TO 16.

NG

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

11.

CHECK ECM POWER SUPPLY CIRCUIT-VI

1.

Disconnect ECM harness connector.

2.

Disconnect IPDM E/R harness connector E119.

3.

Check harness continuity between ECM terminal 111 and IPDM E/R terminal 7.
Refer to Wiring Diagram.

4.

Also check harness for short to ground and short to power.

OK or NG

OK

>> GO TO 12.

NG

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

12.

CHECK 20A FUSE

1.

Disconnect 20A fuse (No.53) from IPDM E/R.

2.

Check 20A fuse.

OK or NG

OK

>> GO TO 16.

NG

>> Replace 20A fuse.

13.

CHECK GROUND CONNECTIONS

Loosen and retighten two ground screws on the body. Refer to

EC-90, "Ground Inspection"

.

OK or NG

OK

>> GO TO 14.

NG

>> Repair or replace ground connections.

14.

CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II

1.

Disconnect ECM harness connector.

2.

Check harness continuity between ECM terminals 1, 115, 116 and ground.
Refer to Wiring Diagram.

3.

Also check harness for short to power.

OK or NG

OK

>> GO TO 16.

NG

>> GO TO 15.

15.

DETECT MALFUNCTIONING PART

Continuity should exist.

Continuity should exist.

BBIA0614E

Continuity should exist.

EC-90

< COMPONENT DIAGNOSIS >

[QR25DE]

POWER SUPPLY AND GROUND CIRCUIT

Check the following.
• Harness connectors F32, E2
• Harness for open or short between ECM and ground

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

16.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-46, "Intermittent Incident"

.

OK or NG

OK

>> Replace IPDM E/R.

NG

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

Ground Inspection

INFOID:0000000005273049

Ground connections are very important to the proper operation of electrical and electronic circuits. Ground
connections are often exposed to moisture, dirt and other corrosive elements. The corrosion (rust) can
become an unwanted resistance. This unwanted resistance can change the way a circuit works.
Electronically controlled circuits are very sensitive to proper grounding. A loose or corroded ground can drasti-
cally affect an electronically controlled circuit. A poor or corroded ground can easily affect the circuit. Even
when the ground connection looks clean, there can be a thin film of rust on the surface.
When inspecting a ground connection follow these rules:
• Remove the ground bolt or screw.
• Inspect all mating surfaces for tarnish, dirt, rust, etc.
• Clean as required to assure good contact.
• Reinstall bolt or screw securely.
• Inspect for “add-on” accessories which may be interfering with the ground circuit.
• If several wires are crimped into one ground eyelet terminal, check for proper crimps. Make sure all of the

wires are clean, securely fastened and providing a good ground path. If multiple wires are cased in one eye-
let make sure no ground wires have excess wire insulation.

For detailed ground distribution information, refer to 

PG-27, "Ground Distribution"

.

PBIB1870E