DTC Troubleshooting: P1030 (183)
DTC P1030:
 Fuel Heater Circuit Malfunction
NOTE: Before you troubleshoot, record all freeze data and review the general troubleshooting information.
  1. Turn the ignition switch ON (II).
  1. Clear the DTC with the HDS.
  1. Do the FUEL HEATER ON/OFF in the INSPECTION MENU with the HDS.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P1030 indicated?
YES -
Go to Step 5 .
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the fuel heater the under-hood fuse/relay box and the ECM.■
  1. Turn the ignition switch OFF.
  1. Check the No. 25 FUEL HEATER MONITOR (7.5 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?
YES -
Go to Step 7 .
NO -
Go to Step 8 .
  1. Check the No. 23 FUEL HEATER (30 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?
YES -
Replace the under-hood fuse/relay box, then go to Step 11 .
NO -
Repair short in the wire between the fuel heater and the under-hood fuse/relay box. Also replace the No. 23 FUEL HEATER (30 A) fuse, then go to Step 12 .
  1. Disconnect the fuel heater 2P connector.
  1. Disconnect ECM connector No. 1 (96P).
  1. Check for continuity between ECM connector No. 1 terminal No. 37 and body ground.
Is there continuity?
YES -
Repair short in the wire between the under-hood fuse/relay box and ECM connector No. 1 terminal No. 37. Also replace No. 25 FUEL HEATER MONITOR (7.5 A) fuse in the under-hood fuse/relay box, then go to Step 11 .
NO -
Substitute a known-good under-hood fuse/relay box, then go to Step 11 and recheck. If DTC P1030 is not indicated, replace the original under-hood fuse/relay box, then go to Step 11 . If DTC P1030 is indicated, go to Step 16 .
  1. Reconnect all connectors.
  1. Turn the ignition switch ON (II).
  1. Reset the ECM with the HDS.
  1. Do the FUEL HEATER ON/OFF in the INSPECTION MENU with the HDS.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P1030 indicated?
YES -
Check for poor connections or loose terminals at the fuel heater, the under-hood fuse/relay box, and the ECM, then go to Step 1 .
NO -
Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.■
  1. Reconnect all connectors.
  1. Update the ECM if it does not have the latest software, or substitute a known-good ECM.
  1. Do the FUEL HEATER ON/OFF in the INSPECTION MENU with the HDS.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P1030 indicated?
YES -
Check for poor connections or loose terminals at the fuel heater, the under-hood fuse/relay box, and the ECM. If the ECM was updated, substitute a known-good ECM, then go to Step 18 . If the ECM was substituted, go to Step 1 .
NO -
If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.■