Nissan Frontier D22. Manual - part 508

IGNITION SIGNAL

EC-1135

[VG33E]

C

D

E

F

G

H

I

J

K

L

M

A

EC

Wiring Diagram

UBS00DQ5

BBWA0496E

EC-1136

[VG33E]

IGNITION SIGNAL

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 the ECM terminals, such as the ground.

: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)

Diagnostic Procedure

UBS00DQ6

1. 

INSPECTION START

Turn ignition switch OFF, and restart engine.
Is engine running?

Yes or No

Yes (With CONSULT-II)>>GO TO 2.
Yes (Without CONSULT-II)>>GO TO 3.
No

>> GO TO 4.

2. 

CHECK OVERALL FUNCTION

With CONSULT-II

1.

Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT-II.

2.

Make sure that all circuits do not produce a momentary engine
speed drop.

OK or NG

OK

>> INSPECTION END.

NG

>> GO TO 4.

TER-

MINAL 

NO.

WIRE 

COLOR

ITEM

CONDITION

DATA (DC Voltage)

1

PU/W

Ignition signal

[Engine is running]

●

Idle speed

NOTE:
The pulse cycle changes depending on rpm at 
idle

Approximately 0.7V

[Engine is running] 

●

Engine speed is 2,000 rpm

1.1 - 1.5V

SEF988U

SEF989U

SEF070Y

IGNITION SIGNAL

EC-1137

[VG33E]

C

D

E

F

G

H

I

J

K

L

M

A

EC

3. 

CHECK OVERALL FUNCTION

 Without CONSULT-II

1.

Let engine idle.

2.

Read the voltage signal between ECM terminal 1 and ground
with an oscilloscope.

3.

Verify that the oscilloscope screen shows the signal wave as
shown below.

OK or NG

OK

>> INSPECTION END.

NG

>> GO TO 4.

4. 

CHECK IGNITION COIL POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect ignition coil harness connector.

3.

Turn ignition switch ON.

4.

Check voltage between terminal 7 and ground with CONSULT-II
or tester.

OK or NG

OK

>> GO TO 6.

NG

>> GO TO 5.

5. 

DETECT MALFUNCTIONING PART

Check the following.

●

Harness connectors E43, M65

●

Harness connectors M59, F27

●

Harness for open or short between ignition coil and ignition switch

>> Repair harness or connectors.

PBIB1431E

SEF988U

AEC656A

Voltage: Battery voltage

SEF721U

EC-1138

[VG33E]

IGNITION SIGNAL

6. 

CHECK POWER TRANSISTOR GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Disconnect power transistor harness connector.

3.

Check harness continuity between power transistor terminal 2 and engine ground. Refer to Wiring Dia-
gram.

4.

Also check harness for short to power.

OK or NG

OK

>> GO TO 7.

NG

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

7. 

CHECK INPUT SIGNAL CIRCUIT

1.

Strip tape covering resistor.

2.

Disconnect resistor harness connector.

3.

Check harness continuity between ignition coil terminal 8 and resistor terminal 1, resistor terminal 2 and
ECM terminal 2. Refer to Wiring Diagram.

4.

Also check for short to ground and short to power.

OK or NG

OK

>> GO TO 8.

NG

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

8. 

CHECK RESISTOR

Check resistance between resistor terminals 1 and 2.

OK or NG

OK

>> GO TO 9.

NG

>> Replace resistor.

9. 

CHECK POWER TRANSISTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Disconnect ECM harness connector.

2.

Check harness continuity between ECM terminal 1 and power transistor terminal 1. Refer to Wiring Dia-
gram.

3.

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

OK or NG

OK

>> GO TO 10.

NG

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

Continuity should exist.

Continuity should exist.

Resistance: Approximately 2.2

Ω [at 25°C (77°F]

SEF240V

Continuity should exist.