DTC Troubleshooting

DTC Troubleshooting: P1298

DTC P1298: ELD Circuit High Voltage

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information. Reading and Clearing Diagnostic Trouble Codes

1. Start the engine, and let it idle.

2. Check the ELD in the DATA LIST with the HDS.

Is 0.2 A or less indicated?
YES - Go to step 3.

NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the ELD and the PCM.


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

4. Disconnect the ELD 3P connector.

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

6. Measure the voltage between ELD 3P connector terminal No. 1 and body ground.

Is there battery voltage?
YES - Go to step 7.

NO - Repair open in the wire between the No. 18 ACG (15 A) fuse in the driver's under-dash fuse/relay box and the ELD, then go to step 14.






7. Turn the ignition switch to LOCK (0).

8. Connect ELD 3P connector terminal No. 3 to body ground with a jumper wire.

9. Jump the SCS line with the HDS.

10. Disconnect PCM connector E (31P).






11. Check for continuity between PCM connector terminal E18 and body ground.

Is there continuity?
YES - Go to step 12.

NO - Repair open in the wire between the PCM (E18) and the ELD, then go to step 14.






12. Check for continuity between ELD 3P connector terminal No. 2 and body ground.

Is there continuity?
YES - Go to step 13.

NO - Repair open in the wire between the ELD and G301, then go to step 14.






13. Replace the under-hood fuse/relay box. Under-Hood Fuse/Relay Box Removal/Installation

14. Reconnect all connectors.

15. Turn the ignition switch to ON (II).

16. Reset the PCM with the HDS.

17. Do the PCM idle learn procedure. PCM Idle Learn Procedure

18. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P1298 indicated?
YES - Go to step 19.

NO - Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.


19. Update the PCM if it does not have the latest software, PCM Update or substitute a known-good PCM. Reading and Clearing Diagnostic Trouble Codes

20. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P1298 indicated?
YES - Check for poor connections or loose terminals at the ELD unit and the PCM. If the PCM was updated, substitute a known-good PCM, Reading and Clearing Diagnostic Trouble Codes then recheck. If the PCM was substituted, go to step 1.

NO - If the PCM was updated, 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.