No Response From PCM (Powertrain Control Module)
NO RESPONSE FROM POWERTRAIN CONTROL MODULENo Response From Powertrain Control Module:
POSSIBLE CAUSES
- Fused B+ circuit open
- Fused engine control relay output circuit open
- PCM ground circuits
- SCI receive circuit open
- SCI receive circuit shorted to ground
- SCI receive circuit shorted to voltage
- SCI transmit circuit open
- SCI transmit circuit shorted to ground
- SCI transmit circuit shorted to voltage
- Powertrain control module
DIAGNOSTIC TEST
1. CHECK COMMUNICATION WITH OTHER MODULES
Turn the ignition on.
Using the DRB III(R), attempt to communicate with any other module.
Q: Is the DRB III(R) able to communicate with the module selected?
YES: Go to 2
NO: Perform Symptom No Response From All Modules. No Response From All Modules
2. FUSED B(+) CIRCUIT OPEN
Turn the ignition off.
Disconnect the PCM C5 harness connector.
NOTE: Check connector - Clean/repair as necessary.
Turn the ignition on.
Measure the voltage of the Fused B(+) circuit at the PCM C5 harness connector.
Q: Is the voltage above 10 volts?
YES: Go to 3
NO: Repair the Fused B(+) circuit for an open. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
3. FUSED ENGINE CONTROL RELAY OUTPUT CIRCUIT OPEN
With the ignition on.
Measure the voltage of the Fused Engine Control Relay Output circuit at the PCM C5 harness connector.
Q: Is the voltage above 10 volts?
YES: Go to 4
NO: Repair the Fused Engine Control Relay Output circuit for an open. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
4. PCM GROUND CIRCUITS OPEN
Turn the ignition off.
Measure the resistance of the Ground circuits from the PCM C5 harness connector to ground.
Q: Is the resistance below 5.0 ohms on each ground circuit?
YES: Go to 5
NO: Repair the Ground circuit(s) for an open. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
5. SCI RECEIVE CIRCUIT OPEN
With the ignition off.
Disconnect the PCM C4 harness connector.
NOTE: Check connector - Clean/repair as necessary.
Measure the resistance of the PCM SCI Receive circuit from the PCM C4 harness connector to the DLC.
Q: Is the resistance below 5.0 ohms?
YES: Go to 6
NO: Repair the PCM SCI Receive circuit for an open. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
6. SCI RECEIVE CIRCUIT SHORTED TO GROUND
With the ignition off.
Measure the resistance between ground and the PCM SCI Receive circuit.
Q: Is the resistance above 100 kohms?
YES: Go to 7
NO: Repair the PCM SCI Receive circuit for a short to ground. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
7. SCI RECEIVE CIRCUIT SHORTED TO VOLTAGE
Turn the ignition on.
Measure the voltage of the PCM SCI Receive circuit at the DLC.
Q: Is the voltage below 0.5 volt?
YES: Go to 8
NO: Repair the PCM SCI Receive circuit for a short to voltage. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
8. SCI TRANSMIT CIRCUIT OPEN
Turn the ignition off.
Measure the resistance of the PCM SCI Transmit circuit from the PCM harness connector to the DLC.
Q: Is the resistance below 5.0 ohms?
YES: Go to 9
NO: Repair the PCM SCI Transmit circuit for an open. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
9. SCI TRANSMIT CIRCUIT SHORTED TO GROUND
With the ignition off.
Measure the resistance between ground and the PCM SCI Transmit circuit.
Q: Is the resistance above 100 kohms?
YES: Go to 10
NO: Repair the PCM SCI Transmit circuit for a short to ground. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
10. SCI TRANSMIT CIRCUIT SHORTED TO VOLTAGE
Turn the ignition on.
Measure the voltage of the PCM SCI Transmit circuit at the DLC.
Q: Is the voltage below 0.5 volt?
YES: Replace the Powertrain Control Module. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
NO: Repair the PCM SCI Transmit circuit for a short to voltage. Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2