DTC Troubleshooting: P1030 (183-1)

DTC P1030:  Fuel Heater Circuit Malfunction

1.Turn the ignition switch ON (II).

2.Clear the DTC with the HDS.

3.Do the FUEL HEATER ON/OFF in the INSPECTION MENU with the HDS.

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

Is DTC P1030 indicated?


YES - Go to 5.


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


5.Turn the ignition switch OFF.

6.Check the No. 31 FUEL HEATER MONITOR (7.5 A) fuse in the under-hood fuse/relay box.

Is the fuse OK?


YES - Go to 7.


NO - Replace the No. 31 FUEL HEATER MONITOR (7.5 A) fuse, then go to 15.


7.Check the No. 12 +B FUEL HEATER (30 A) fuse in the under-hood fuse/relay box.

Is the fuse OK?


YES - Go to 8.


NO -

  • Repair short in the wire between the No. 12 +B FUEL HEATER (30 A) fuse and the fuel heater relay. Also replace the No. 12 +B FUEL HEATER (30 A) fuse, then go to 15.
  • Repair short in the wire between the fuel heater relay and the No. 31 FUEL HEATER MONITOR (7.5 A) fuse in the under-hood fuse/relay box, then go to 15.

8.Disconnect the fuel heater relay.

9.Check the fuel heater relay.

Is the fuel heater relay OK?


YES - Go to 10.


NO - Replace the fuel heater relay, then go to 14.


10.Measure voltage between fuel heater relay 4P connector terminal No. 1 and body ground.

 

Is there battery voltage?


YES - Go to 11.


NO - Repair open in the wire between the No. 12 +B FUEL HEATER (30 A) fuse and the fuel heater relay, then go to 14.

11.Disconnect the fuel heater 2P connector.

12.Disconnect ECM connector No. 1 (96P).

13.Check for continuity between ECM connector No. 1 terminal No. 37 and body ground.

 

Is there continuity?


YES - Repair short in the wire between No. 31 FUEL HEATER MONITOR (7.5 A) fuse and ECM connector No. 1 terminal No. 37. Also replace No. 31 FUEL HEATER MONITOR (7.5 A) fuse in the under-hood fuse/relay box, then go to 14.


NO - Go to 19.


14.Reconnect all connectors.

15.Turn the ignition switch ON (II).

16.Reset the ECM with the HDS.

17.Do the FUEL HEATER ON/OFF in the INSPECTION MENU with the HDS.

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

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P1030 is indicated, check for poor connections or loose terminals at the fuel heater relay and the ECM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - Troubleshooting is complete.n


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

20.Do the FUEL HEATER ON/OFF in the INSPECTION MENU with the HDS.

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

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P1030 is indicated, check for poor connections or loose terminals at the fuel heater relay 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