DTC Confirmation Test (Overall Function Check)
NOTE:
Use the following test to check overall function of fuel level sensor. During this test, DTC may not be confirmed.
Malfunction is detected when fuel level sensor output does not change when vehicle has been driven a long distance. Possible causes are:
- Fuel level sensor circuit open or shorted.
- Defective fuel level sensor.
- To check overall function of fuel level sensor, release fuel system pressure. See FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Remove fuel feed hose from fuel pump assembly located behind access cover under rear seat.
- Connect a fuel hose to fuel pump assembly. Place other end of hose into a suitable fuel container. Turn ignition off. Measure voltage between ground and fuel level sensor signal circuit at ECM terminal No. 83 (Green wire) by backprobing. See Figure. Turn ignition on and note voltage reading.
- Using suitable equipment, drain 7.93 gals. (30.0 L) of fuel from tank and note voltage reading. Refill tank with drained fuel. Voltage should change more than .03 volt during draining and refilling.
CAUTION:
DO NOT use ECM ground terminals when measuring voltage.