Nissan Frontier. Manual - part 394

POWER SUPPLY AND GROUND CIRCUIT

EC-147

< DTC/CIRCUIT DIAGNOSIS >

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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 or tester.

OK or NG

OK

>> Go to 

EC-446

.

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 105 and ground with CONSULT 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 24 and ground with CONSULT 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.

2. Disconnect IPDM E/R harness connector E119.

3. Check harness continuity between ECM terminals 105 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.

Voltage: Battery voltage

PBIB2658E

Voltage:

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

Voltage: Battery voltage

Continuity should exist.

EC-148

< DTC/CIRCUIT DIAGNOSIS >

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POWER SUPPLY AND GROUND CIRCUIT

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 24 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-149, "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 12, 16, 107, 108, 111, 112 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

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-42, "Intermittent Incident"

.

OK or NG

Continuity should exist.

BBIA0614E

Continuity should exist.

POWER SUPPLY AND GROUND CIRCUIT

EC-149

< DTC/CIRCUIT DIAGNOSIS >

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OK

>> Replace IPDM E/R.

NG

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

Ground Inspection

INFOID:0000000009480773

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

EC-150

< DTC/CIRCUIT DIAGNOSIS >

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U0101 CAN COMM CIRCUIT

U0101 CAN COMM CIRCUIT

Description

INFOID:0000000009480774

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-

tiplex communication line with high data communication speed and excellent error detection ability. Many elec-

tronic control units are equipped onto a vehicle, and each control unit shares information and links with other

control units during operation (not independent). In CAN communication, control units are connected with 2

communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.

Each control unit transmits/receives data but selectively reads required data only.

On Board Diagnosis Logic

INFOID:0000000009480775

This self-diagnosis has the one trip detection logic.

DTC Confirmation Procedure

INFOID:0000000009480776

1. Turn ignition switch ON and wait at least 3 seconds.
2. Check DTC.
3. If DTC is detected, go to 

EC-150, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000009480777

Go to 

LAN-14, "Trouble Diagnosis Flow Chart"

.

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

 U0101

0101

Lost communication 
with TCM

When ECM is not transmitting or receiving CAN 
communication signal of OBD (emission related di-
agnosis) with TCM for 2 seconds or more.

• CAN communication line between 

TCM and ECM

• CAN communication line open or 

shorted