DTC P0183: Fuel Temperature Sensor "A" Circuit High Input
- Turn ignition off. Connect scan tool. Start engine. Observe fuel temperature sensor signal. If displayed value is less than -40°F (-40°C), go to next step. If displayed value is more than -40°F (-40°C), check for poor contact in ECM or fuel pump connectors, or for an open in wiring of fuel pump circuit. See appropriate wiring diagram in WIRING DIAGRAMS article. Repair as necessary and retest system.
- Turn ignition off. Disconnect 6-pin fuel pump connector. Using a voltmeter connected to ground, measure voltage at fuel pump connector terminal No. 6. See Fig 1. If voltage is more than 10 volts, repair short circuit in wiring between ECM and fuel pump connectors. If voltage is 10 volts or less, leave voltmeter connected and go to next step.
- Turn ignition on and recheck voltage. If voltage is more than 10 volts, repair short to voltage in wiring between fuel pump and ECM connectors. If voltage is 10 volts or less, go to next step.
- Recheck voltage. If voltage is more than 4 volts, go to next step. If voltage is 4 volts or less, repair open in wiring between fuel pump connector and ECM, or for poor contact at fuel pump or ECM connectors.
- Turn ignition off. Using an ohmmeter, measure resistance between ground and fuel pump connector terminal No. 5. If resistance is less than 5 ohms, replace fuel temperature sensor. If resistance is 5 ohms or more, repair open in wiring between fuel pump connector and ECM, or check for poor contact at fuel pump or ECM connectors. Check for faulty ground circuit to fuel pump connector.