Component Tests and General Diagnostics

Ignition Control Circuit Diagnostic Chart:

Ignition Control Circuit:

DIAGNOSTIC CHART AND DIAGRAM

1. CHECK OUTPUT SIGNAL FOR ECU. Measure voltage between ECU connector terminal and body while cranking the engine.

Connector & Terminal/Specified value
#1: (B62) No. 10 Body/5 V, min.
#2: (B62) No. 8 - Body/5 V, min.
#3: (B62) No. 9 - Body/5 V, min.
#4: (B62) No. 7 - Body/5 V, min.
#5: (B62) No. 21 - Body/5 V, min.
#6: (B62) No. 16 - Body/5 V, min.

ECM And Ignitor Connectors:

2. CHECK HARNESS CONNECTOR BETWEEN ECU AND IGNITOR.
1) Turn ignition switch to "OFF".
2) Disconnect connectors from ECU and ignitor.
3) Measure resistance of harness between ECU and ignitor.

Connector & Terminal/Specified value
#1: (B62) No. 10 - (B12) No. 1/0 ohms
#2: (B62) No. 8 - (B12) No. 2/0 ohms
#3: (B62) No. 9 - (B12) No. 3/0 ohms
#4: (B62) No. 7 - (B12) No. 5/0 ohms
#5: (B62) No. 21 - (B12) No. 6/0 ohms
#6: (B62) No. 16 - (B12) No. 7/0 ohms
Body - (B12) No. 4/0 ohms

3. CHECK IGNITOR OUTPUT SIGNAL.
1) Connect all connectors.
2) Measure voltage between ignitor output connector and body while cranking the engine.


Connector & Terminal/Specified value
#1: (811) No. 1 - Body/5 V, min.
#2: (B11) No. 2 - Body/5 V, min.
#3: (B11) No. 3 - Body/5 V, min.
#4: (B11) No. 4 - Body/5 V, min.
#5: (B11) No. 5 - Body/5 V, min.
#6: (811) No. 6 - Body/5 V, min.

Ignitor And Coil Connectors:

4. CHECK HARNESS CONNECTOR BETWEEN IGNITOR AND EACH IGNITION COIL.
1) Turn ignition switch to "OFF".
2) Disconnect ignitor connector (B31) and each ignition coil connector from engine harness.
3) Measure resistance of harness connector between ignitor and each ignition coil.


Connector & Terminal/Specified value
#1: (811) No. 1 - (B27) No.2/0 ohms
#2: (B11) No. 2 - (830) No. 2/0 ohms
#3: (B11) No. 3 - (B28) No. 2/0 ohms
#4: (811) No.4 - (831) No.2/0 ohms
#5: (B11) No. 5 - (B29) No. 2/0 ohms
#6: (811) No. 6 - (832) No. 2/0 ohms

5. CHECK POWER SUPPLY CIRCUIT OF IGNITION COIL.
1) Connect all connectors.
2) Turn ignition switch to "ON".
3) Measure voltage between ignition coil terminal and body.


Connector & Terminal/Specified value
#1: (E27) No. 1 - Body/12 V, min.
#2: (E30) No. 1 - Body/12 V, min.
#3: (E28) No. 1 - Body/12 V, min.
#4: (E31) No. 1 - Body/12 V, min.
#5: (E29) No. 1 - Body/12 V, min.
#6: (E30) No. 1 - Body/12 V, min.



6. CHECK IGNITION SYSTEM FOR SPARK WITH NEW IGNITION COIL.
1) Turn ignition switch to "OFF".
2) Remove each ignition coil from cylinder head.
3) Replace ignition coil with new one.
4) Crank engine to check that spark occurs at each cylinder.