DTC Troubleshooting

Control System DTCs

DTC Troubleshooting: P0563

DTC P0563 : ECM Power Source Circuit Unexpected Voltage

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information How To Troubleshoot The Fuel And Emissions Systems.

1. Problem verification:

Problem verification
-1. Turn the ignition switch to ON (II).

-2. Clear the DTC with the HDS.

-3. Turn the ignition switch to LOCK (0).

-4. Wait 10 seconds.

-5. Turn the ignition switch to ON (II).

-6. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0563 indicated?
-YES- The failure is duplicated. Go to step 2.
-NO- Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at PGM-FI main relay 1 and the ECM.

2. Determine possible failure area (FI_MAIN_RLY_OUT line, others):

Determine possible failure area (FI_MAIN_RLY_OUT line, others)
-1. Turn the ignition switch to LOCK (0).

-2. Jump the SCS line with the HDS.

-3. Disconnect the following connector.





-4. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- Go to step 5.
-NO- Go to step 3.

3. Shorted wire check (FI_MAIN_RLY_CL- line):

Shorted wire check (FI_MAIN_RLY_CL- line)
-1. Remove PGM-FI main relay 1 (A) from the under-dash fuse/relay box.





-2. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- Repair a short in the FI_MAIN_RLY_CL- wire between the ECM (A7) and PGM-FI main relay 1, then do the repair verification.
-NO- The FI_MAIN_RLY_CL- wire is OK. Go to step 4.

4. Relay check:

Relay check
-1. Test PGM-FI main relay 1 Testing and Inspection.

Is PGM-FI main relay 1 OK?
-YES- Update the ECM ECM/PCM Update if it does not have the latest software, or substitute a known-good ECM Service and Repair, then do the repair verification.
-NO- Replace PGM-FI main relay 1, then do the repair verification.

5. Shorted wire check (FI_MAIN_RLY_OUT line to power):

Shorted wire check (FI_MAIN_RLY_OUT line to power)
-1. Remove PGM-FI main relay 1 (A) from the under-dash fuse/relay box.





-2. Measure the voltage between test points 1 and 2.









Is there battery voltage?
-YES- Repair a short to power in the FI_MAIN_RLY_OUT wire between the ECM (A9) and PGM-FI main relay 1, then do the repair verification.
-NO- The FI_MAIN_RLY_OUT wire is OK. Go to step 6.

6. Relay check:

Relay check
-1. Test PGM-FI main relay 1 Testing and Inspection.

Is PGM-FI main relay 1 OK?
-YES- PGM-FI main relay 1 is OK. Update the ECM ECM/PCM Update if it does not have the latest software, or substitute a known-good ECM Service and Repair, then do the repair verification.
-NO- Replace PGM-FI main relay 1, then do the repair verification.

Repair verification:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect all connectors.

-3. Turn the ignition switch to ON (II).

-4. Reset the ECM with the HDS How To Troubleshoot The Fuel And Emissions Systems.

-5. Do the ECM idle learn procedure ECM/PCM Idle Learn Procedure.

-6. Turn the ignition switch to LOCK (0).

-7. Wait 10 seconds.

-8. Turn the ignition switch to ON (II).

-9. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0563 indicated?
-YES- Check for poor connections or loose terminals at PGM-FI main relay 1 and the ECM. If the ECM was updated, substitute a known-good ECM Service and Repair, then recheck. If the ECM was substituted, go to step 1.
-NO- Troubleshooting is complete. If the ECM was substituted, replace the original ECM Service and Repair. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.