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Fuel Gauge Inoperative Or Inaccurate

  1. If vehicle has been checked for Diagnostic Trouble Codes (DTCs), go to next step. If vehicle has not been checked for DTCs, see appropriate TESTS W/CODES article in ENGINE PERFORMANCE section:
  2. Disconnect Powertrain Control Module (PCM) Blue 80-pin connector C1. Turn ignition switch to RUN position. If fuel gauge reads full, go to next step. If fuel gauge does not read full, go to step 5).
  3. Turn ignition switch to OFF position. Ensure PCM connector C1 is still disconnected. Connect a 3-amp fused jumper wire between PCM connector C1, terminal No. 3 (Orange wire) and ground. If fuel gauge reads empty, go to step 7). If fuel gauge does not read empty, go to next step.
  4. Remove instrument cluster. See INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. Using DVOM, check for continuity between PCM connector C1, terminal No. 3 (Orange wire) and instrument cluster Black 32-pin connector terminal C14 (Orange wire). If continuity exists, go to step 6). If continuity does not exist, go to next step.
  5. Repair open in circuit No. 55 (Orange wire) between PCM connector C1 and instrument cluster. Recheck system operation.
  6. Replace instrument cluster. See INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. Recheck system operation.
  7. Turn ignition switch to OFF position. Disconnect PCM Clear 80-pin connector C2. Disconnect Black 6-pin connector C405 (body wiring harness-to-electronic brake control and fuel sender wiring harnesses, located under vehicle, behind driver's seat). Connect a 3-amp fused jumper wire between connector C405 terminal "F" (Purple wire) and ground. Using DVOM, check for continuity between PCM connector C2, terminal No. 69 (Purple wire) and ground. If continuity exists, go to next step. If continuity does not exist, go to step 9).
  8. Disconnect 3-amp fused jumper wire. Leave DVOM connected as specified in step 7). If continuity exists, go to next step. If continuity does not exist, go to step 10).
  9. Repair open, excessive resistance or short to ground in circuit No. 30 (Purple wire) between PCM connector C2 and fuel level sending unit. Recheck system operation.
  10. Reconnect PCM connectors C1 and C2. Connect Instrument Panel Tester (J-33431-C) or resistor of equal value between connector C405 terminal "F" (Purple wire) and ground. Turn ignition switch to RUN position. Vary resistance of instrument panel tester as specified. See TESTER RESISTANCE SPECIFICATIONS  table. If fuel gauge indicator responds as indicated, go to next step. If fuel gauge indicator does not respond as indicated, go to step 13).
    TESTER RESISTANCE SPECIFICATIONS

    Ohms Fuel Gauge Level
    245 Full
    180 3/4
    160 1/2
    100 1/4
    42 Empty
  11. Turn ignition switch to OFF position. Disconnect PCM Blue 80-pin connector C1. Check for poor connection or open in circuit No. 808 (Black wire) between PCM connector C1, terminal No. 17 and connector C405 terminal "D". Repair as necessary and recheck system operation. If circuit is okay, go to next step.
  12. Check for poor terminal connections at fuel tank sending unit. Check float for obstructions or damage. Repair as necessary and recheck system operation. If no problems are found, replace fuel tank sending unit. Recheck system operation.
  13. Replace PCM. See procedures in appropriate REMOVE/INSTALL/OVERHAUL article in ENGINE PERFORMANCE section:

Recheck system operation.

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