Operation CHARM: Car repair manuals for everyone.

P0685






P0685 - ASD/Main Control Circuit






For wiring diagrams, refer to.

When Monitored: With the control circuit active and battery voltage greater than 10.4 volts.

Set Condition: The PCM detects an open or shorted condition in the ASD Relay Control circuit.






Always perform the pre-diagnostic troubleshooting procedure before proceeding. Refer to => Non-DTC Based Diagnostics. Pre-Diagnostic Troubleshooting Procedure

Test Step 1 - DTC is Active

Turn the ignition ON.

With the scan tool, clear DTCs in the PCM.

With the scan tool, actuate the auto shutdown relay control state.

With the scan tool, select view DTCs.

Is the status active for this DTC?

Yes

Go to Test Step 2 => [ Test
Step 2 - Fused B+ Circuit Open or High Resistance ]

No

Refer to the checking for an intermittent DTC diagnostic procedure. Refer to => Non-DTC Based Diagnostics. Checking for an Intermittent DTC

Test Step 2 - Fused B+ Circuit Open or High Resistance






Turn the ignition OFF.

Remove the ASD Relay.

Using a test lamp connected to ground, check both fused B+ circuits in the auto shutdown relay connector.

The test lamp should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test lamp illuminated and bright?

Yes

Go to Test Step 3 => [ Test
Step 3 - ASD Relay Control Circuit Shorted to Voltage ]

No

Repair the fused B+ circuits for an open circuit or high resistance.

Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test

Test Step 3 - ASD Relay Control Circuit Shorted to Voltage






Turn the ignition OFF.

Disconnect the PCM connector.

Turn the ignition ON.

Measure the voltage of the ASD relay control circuit in the auto shutdown relay connector.

Is there any voltage present?

Yes

Repair the ASD relay control circuit for a short to voltage.

Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test

No

Go to Test Step 4 => [ Test
Step 4 - ASD Relay Control Circuit Shorted to Ground ]

Test Step 4 - ASD Relay Control Circuit Shorted to Ground






Turn the ignition OFF.

Measure the resistance between ground and the ASD relay control circuit in the auto shutdown relay connector.

Is the resistance less than 100 ohms?

Yes

Repair the ASD relay control circuit for a short to ground.

Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test

No

Go to Test Step 5 => [ Test
Step 5 - ASD Relay Control Circuit Open or High Resistance ]

Test Step 5 - ASD Relay Control Circuit Open or High Resistance






Measure the resistance of the ASD relay control circuit between the auto shutdown relay connector and the PCM harness connector.

Is the resistance less than 5.0 ohms?

Yes

Go to Test Step 6 => [ Test
Step 6 - Auto Shutdown Relay ]

No

Repair the ASD relay control circuit for an open or high resistance.

Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test

Test Step 6 - Auto Shutdown Relay






Connect the PCM connector.

Turn the ignition ON.

With the scan tool, actuate the auto shutdown relay control state control to the ON position.

Using a test lamp connected to 12 volts, check the relay control circuit in the auto shutdown relay harness connector.

If the DTC is active, the actuation test may not be allowed by the PCM. If may be necessary to clear the DTCs before starting the actuation.

The test lamp should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test lamp illuminated and bright?

Yes

Replace the auto shutdown relay.

Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test

No

Go to Test Step 7 => [ Test
Step 7 - PCM ]

Test Step 7 - PCM

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the auto shutdown relay and the PCM.

Look for any chafed, pierced, pinched, or partially broken wires.

Look for broken, bent, pushed out or corroded terminals.

Refer to any technical service bulletins that may apply.

Were any problems found?

Yes

Repair as necessary.

Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test

No

Replace and program the PCM.

Perform the PCM Verification Test. Refer to => Non-DTC
Based Diagnostics. PCM Verification Test