DTC Troubleshooting: P1298 (20-2)

DTC P1298:  ELD Circuit High Voltage


NOTE: Before you troubleshoot, record all freeze data and review the general troubleshooting information.

1.Turn the ignition switch ON (II).

2.Check the ELECTRICAL LOAD DETECTOR in the DATA LIST with the HDS.

Is 0.2 A or less indicated?


YES - Go to 3.


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


3.Turn the ignition switch OFF.

4.Disconnect the ELD 3P connector.

5.Turn the ignition switch ON (II).

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

 

Is there battery voltage?


YES - Go to 7.


NO - Repair open in the wire between the No. 3 ALTERNATOR (10 A) fuse and the ELD, then go to 15.

7.Turn the ignition switch OFF, and wait 1 minute.

8.Disconnect ECM connector No. 2 (58P).

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

 

10.Check for continuity between ECM connector No. 2 terminal No. 23 and body ground.

 

Is there continuity?


YES - Go to 11.


NO - Repair open in the wire between the ELD and ECM connector No. 2 terminal No. 23, then go to 15.

11.Connect ELD 3P connector terminal No. 2 to body ground with a jumper wire.

 

12.Check for continuity between ECM connector No. 2 terminal No. 21 and body ground.

 

Is there continuity?


YES - Go to 13.


NO - Repair open in the wire between the ELD and ECM connector No. 2 terminal No. 21, then go to 15.

13.Turn the ignition switch OFF.

14.Replace the under-hood fuse/relay box.

15.Reconnect all connectors.

16.Turn the ignition switch ON (II).

17.Reset the ECM with the HDS.

18.Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - Go to 19.


NO - Troubleshooting is complete.n


19.Update the ECM if it does not have the latest software, or substitute a known-good ECM.

20.Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P1298 is indicated, check for poor connections or loose terminals at the ELD and the ECM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM.n