Glow Plug Indicator Circuit Troubleshooting

Turn the ignition switch ON (II). Do the gauge self-diagnostic procedure. Does the glow plug indicator flash?
YES | - | Go to Step 3 .
NO | - | Substitute a known-good gauge assembly, and recheck. If the glow plug indicator circuit is OK, replace the original gauge assembly.■
Turn the ignition switch OFF. Turn the ignition switch ON (II), and watch the glow plug indicator. Does the glow plug indicator stay off?
YES | - | Go to Step 7 .
NO | - | Go to Step 5 .
Turn the ignition switch OFF. Turn the ignition switch ON (II), and watch the glow plug indicator. Does the glow plug indicator stay on?
YES | - | Go to Step 12 .
NO | - | The glow plug indicator circuit is OK.■
Try to start the engine. Does the engine start?
YES | - | Go to Step 8 .
NO | - | Go to Step 16 .
Turn the ignition switch OFF, and wait 30 seconds. Disconnect the gauge control module 36P connector. Disconnect ECM connector No. 2 (58P). Check for continuity between ECM connector No. 2 terminal No. 33 and gauge control module 36P connector terminal No. 28. Is there continuity?
YES | - | Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM. ■
NO | - | Repair open in the wire between the gauge assembly and ECM connector No. 2 terminal No. 33.■
Turn the ignition switch OFF, and wait 30 seconds. Disconnect the gauge control module 36P connector. Disconnect ECM connector No. 2 (58P). |

Check for continuity between ECM connector No. 2 terminal No. 33 and body ground. Is there continuity?
YES | - | Repair short in the wire between the gauge assembly and ECM connector No. 2 terminal No. 33.■
NO | - | Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM. ■
Press the inertia switch button. Try to start the engine. Does the engine start?
YES | - | Troubleshooting is complete.■
NO | - | Go to Step 18 .
Check PGM-FI main relay 1. Is PGM-FI main relay 1 OK?
YES | - | Go to Step 19 .
NO | - | Replace PGM-FI main relay 1.■
Inspect the No. 8 FI ECU (ECM) (20 A) fuse in the under-hood fuse/relay box. Is the fuse OK?
YES | - | Go to Step 26 .
NO | - | Go to Step 20 .
Disconnect PGM-FI main relay 1. |

Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 1 and No. 4 individually. Is there continuity?
YES | - | Repair short in the wire between PGM-FI main relay 1 and the No. 8 FI ECU (ECM) (20 A) fuse. Also replace the No. 8 FI ECU (ECM) (20 A) fuse.■
NO | - | Go to Step 22 .
Turn the ignition switch OFF, and wait 30 seconds. Disconnect ECM connector No. 2 (58P). Disconnect the fuel rail pressure control valve 2P connector. |

Check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and body ground. Is there continuity?
YES | - | Repair short in the wire between PGM-FI main relay 1, the fuel rail pressure control valve and ECM connector No. 2 terminal No. 1, No. 3 or No. 5. Also replace the No. 8 FI ECU (ECM) (20 A) fuse.■
NO | - | Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM. ■
Turn the ignition switch OFF. Disconnect PGM-FI main relay 1. |

Measure voltage between body ground and PGM-FI main relay 1 4P connector terminals No. 1 and No. 4 individually. Is there battery voltage?
YES | - | Go to Step 29 .
NO | - | Repair open in the wire between PGM-FI main relay 1 and the No. 8 FI ECU (ECM) (20 A) fuse.■
Disconnect ECM connector No. 2 (58P). |

Connect PGM-FI main relay 1 4P connector terminal No. 3 to body ground with a jumper wire. |

Check for continuity between ECM connector No. 2 terminal No. 19 and body ground. Is there continuity?
YES | - | Go to Step 35 .
NO | - | Go to Step 32 .
Disconnect the inertia switch 3P connector. |

Connect inertia switch 3P connector terminals No. 1 and No. 3 with a jumper wire. |

Check for continuity between ECM connector No. 2 terminal No. 19 and body ground. Is there continuity?
YES | - | Replace the inertia switch .■
NO | - | Repair open in the wire between PGM-FI main relay 1 and ECM connector No. 2 terminal No. 19.■

Measure voltage between ECM connector No. 2 terminal No. 35 and body ground. Is there battery voltage?
YES | - | Go to Step 37 .
NO | - | Go to Step 36 .
Inspect the No. 18 IG ACG (15 A) fuse in the under-dash fuse/relay box. Is the fuse OK?
YES | - | Repair open in the wire between the No. 18 IG ACG (15 A) fuse and ECM connector No. 2 terminal No. 1.■
NO | - | Repair short in the wire between the No. 18 IG ACG (15 A) fuse and ECM connector No. 2 terminal No. 1.■

Check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and ECM connector No. 2 terminals No. 1, No. 3, and No. 5 individually. Is there continuity?
YES | - | Go to Step 38 .
NO | - | Repair open in the wire between PGM-FI main relay 1 and ECM connector No. 2 terminal No. 1, No. 3 or No. 5.■

Check for continuity between body ground and ECM connector No. 2 terminals No. 2, No. 4, and No. 6 individually. Is there continuity?
YES | - | Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM. ■
NO | - | Repair open in the wire between PGM-FI main relay 1 and ECM connector No. 2 terminal No. 1, No. 3 or No. 5.■