DTC Troubleshooting

Control System DTCs

DTC Troubleshooting: P0563

DTC P0563 : PCM 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:

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

-2. Clear the DTC with the HDS. How to Troubleshoot the Fuel And Emissions Systems

-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 PCM.

2. 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):

-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 PCM (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:

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

Is PGM-FI main relay 1 OK?
-YES- Update the PCM PCM Update if it does not have the latest software, or substitute a known-good PCM 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):

-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 PCM (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:

-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 PCM PCM Update if it does not have the latest software, or substitute a known-good PCM 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 PCM with the HDS How to Troubleshoot the Fuel And Emissions Systems.

-5. Do the PCM idle learn procedure 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 PCM. If the PCM was updated, substitute a known-good PCM Service and Repair, then recheck. If the PCM was substituted, go to step 1.
-NO- Troubleshooting is complete. If the PCM was substituted, replace the original PCM Service and Repair. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.