Nissan Frontier. Manual — part 446

P0850 PNP SWITCH

EC-355

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

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Refer to Wiring Diagram.

3. Also check harness for short to ground and short to power.
OK or NG

OK

>> GO TO 7.

NG

>> GO TO 6.

6.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors E152, M31

• Harness for open or short between ECM and combination meter

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

7.

CHECK PNP INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-III

1. Check harness continuity between A/T assembly terminal 9 and TCM terminal 8.

2. Also check harness for short to ground and short to power.
OK or NG

OK

>> GO TO 8.

NG

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

8.

CHECK INTERMITTENT INCIDENT

Refer to

GI-42, "Intermittent Incident"

.

OK or NG

OK

>> GO TO 9.

NG

>> Repair or replace.

9.

REPLACE COMBINATION METER

Refer to

MWI-5, "METER SYSTEM : System Diagram"

.

>> INSPECTION END

M/T MODELS

1.

CHECK PNP SWITCH GROUND CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Disconnect PNP switch harness connector.

3. Check harness continuity between PNP switch terminal 2 and ground.

Refer to Wiring Diagram.

4. Also check harness for short to power.
OK or NG

OK

>> GO TO 3

NG

>> GO TO 2.

2.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors F14, E5

• Harness for open or short between PNP switch and ground

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

Continuity should exist.

Continuity should exist.

Continuity should exist.

EC-356

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

P0850 PNP SWITCH

3.

CHECK PNP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Disconnect ECM harness connector.

2. Check harness continuity between ECM terminal 101 and PNP switch terminal 1.

Refer to Wiring Diagram.

3. Also check harness for short to ground and short to power.
OK or NG

OK

>> GO TO 5.

NG

>> GO TO 4.

4.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors F14, E5

• Harness for open or short between PNP switch and ECM

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

5.

CHECK PNP SWITCH

Refer to

EC-94, "Wiring Diagram"

.

OK or NG

OK

>> GO TO 6.

NG

>> Replace PNP switch. Refer to

TM-83, "Disassembly"

.

6.

CHECK INTERMITTENT INCIDENT

Refer to

GI-42, "Intermittent Incident"

.

>> INSPECTION END

Continuity should exist.

P1148 CLOSED LOOP CONTROL

EC-357

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

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P1148 CLOSED LOOP CONTROL

On Board Diagnosis Logic

INFOID:0000000009481040

This self-diagnosis has the one trip detection logic.

NOTE:

DTC P1148 is displayed with another DTC for air fuel ratio (A/F) sensor 1.

Perform the trouble diagnosis for the corresponding DTC.

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1148
1148

Closed loop control function

The closed loop control function does not
operate even when vehicle is being driven in
the specified condition.

• Harness or connectors

[The air fuel ratio (A/F) sensor 1 circuit is
open or shorted.]

• Air fuel ratio (A/F) sensor 1
• Air fuel ratio (A/F) sensor 1 heater

EC-358

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

P117A AIR FUEL RATIO

P117A AIR FUEL RATIO

DTC Logic

INFOID:0000000009481041

DTC DETECTION LOGIC

NOTE:

If DTC P117A is displayed with other DTC, first perform the trouble diagnosis for the other DTC. Refer

to

EC-82, "DTC Index"

.

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING-1

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-

ing the next test.

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON.

3. Turn ignition switch OFF and wait at least 10 seconds.

NOTE:

Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.

>> GO TO 2.

2.

PRECONDITIONING-2

1. Turn ignition switch ON.

2. Clear the mixture ratio self-learning value. Refer to

EC-58, "CONSULT Function"

.

Will CONSULT be used?

YES

>> GO TO 3.

NO

>> GO TO 6.

3.

PERFORM DTC CONFIRMATION PROCEDURE-1

1. Turn ignition switch ON.

2. Select “COOLAN TEMP/S” in “DATA MONITOR” mode of “ENGINE” using CONSULT.

3. Start engine.

4. Make sure that “COOLAN TEMP/S” indicates more than 80

°C (176°F).

>> GO TO 4.

4.

PERFORM DTC CONFIRMATION PROCEDURE-2

With CONSULT

1. Select “SYSTEM 1 DIAGNOSIS B B1” and “SYSTEM 1 DIAGNOSIS A B1” in “DATA MONITOR” mode of

“ENGINE” using CONSULT.

2. Drive vehicle under the following conditions for at least 5 consecutive seconds.

CAUTION:

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P117A

AIR FUEL RATIO B1
(AIR FUEL RATIO B1)

ECM detects a lean/rich air fuel ratio state in any
cylinder for a specified length of time.

• Fuel injector
• Exhaust gas leaks
• Incorrect fuel pressure
• Mass air flow sensor
• Intake air leaks
• Lack of fuel
• Incorrect PCV hose connection
• Improper spark plug
• Insufficient compression
• The fuel injector circuit is open or

shorted

• ignition coil
• The ignition signal circuit is open or

shorted