Test B: Incorrect Fuel Gauge Indication

PINPOINT TEST B: INCORRECT FUEL GAUGE INDICATION

B1-B4:

B4-B5:

B6-B8:

B9-B10:

B11-B13:

NOTE: On gasoline-equipped vehicles, the fuel pump module may also be called the fuel tank unit and on diesel-equipped vehicles, the fuel level sender may also be called the fuel level sensor or fuel gauge sensor.

Normal Operation
The fuel pump module (gasoline) or fuel level sender (diesel) is hardwired to the instrument cluster between the signal circuit 29 (YE/WH) and the return circuit 651 (BK/YE), which is grounded internally within the instrument cluster. The instrument cluster provides a reference voltage to the fuel pump module (gasoline) or fuel level sender (diesel) on circuit 29 (YE/WH). As the fuel level changes, a float actuates a variable resistor that alters the fuel level signal voltage. The instrument cluster monitors the changes in voltage and commands the fuel gauge with a corresponding movement of the pointer.

DTC B1202 - is a continuous memory DTC that sets after 33 seconds if the instrument cluster detects an open or short to voltage on the fuel level input, circuit 29 (YE/WH).

DTC B1204 - is a continuous memory DTC that sets after 33 seconds if the instrument cluster detects a short to ground on the fuel level input, circuit 29 (YE/WH).

Possible Causes
- Circuit 29 (YE/WH) open, short to ground or voltage
- Circuit 29 (YE/WH) short to circuit 651 (BK/YE)
- Circuit 651 (BK/YE) open or short to voltage
- Fuel level sensor (float and card)
- Fuel level sender (diesel)
- Fuel pump module (gasoline)
- Fuel tank
- Instrument cluster