Test B: Incorrect Fuel Gauge Indication

PINPOINT TEST B: INCORRECT FUEL GAUGE INDICATION

B1:

B2-B5:

B5-B7:

B7-B8:

B9-B11:

B11-B12:

B13-B14:

B15-B17:

B18:

NOTE:
- The fuel pump module is also called the fuel sender.
- The fuel level sensor is also called the remote fuel sender.

Normal Operation
The fuel tank is a saddle tank design with variable resistance senders, driven by floats, that provide resistances related to fuel height in each side to the instrument cluster. The fuel level is determined using variable resistance fuel sensor units, with an approximate resistance range between 15 ohms ± 2 ohms at empty (E) and 160 ohms ± 4 ohms at full (F). The instrument cluster sends a signal to the fuel pump module through circuit 29 (YE/WH) and returns through circuit 1843 (BK/OG). The instrument cluster sends a signal to the fuel level sensor circuit 1356 (LG/VT) and returns through circuit 1357 (LB/YE). The instrument cluster monitors the resistance readings from the fuel sensors and commands the fuel gauge with a corresponding movement of the pointer. If the instrument cluster detects the fuel level sensor circuitry is open, the fuel gauge defaults to the fuel pump module value only and the fuel gauge indicates E to 1/2 tank. If the instrument cluster detects fuel pump module circuitry is open, the fuel gauge defaults to the empty position.

DTC B1202 - sets when the instrument cluster detects an open or a short to voltage on the fuel pump module signal circuit for more than 33 seconds.

DTC B1204 - sets when the instrument cluster detects a short to ground on the fuel pump module signal circuit for more than 33 seconds.

DTC B2627 - sets when the instrument cluster detects an open or a short to voltage on the fuel level sensor signal circuit for more than 33 seconds.

DTC B2628 - sets when the instrument cluster detects a short to ground on the fuel level sensor signal circuit for more than 33 seconds.

NOTE: Normal operation of the fuel delivery system allows the remote side of the fuel tank (the side opposite of the fuel filler hose) to have less fuel than the side with the fuel pump module (side with the fuel filler hose).

DTC B2879 - sets when the instrument cluster detects a large discrepancy in the amount of fuel (based on input from the fuel senders) between both sides of the fuel tank.

Possible Causes
- Circuit 29 (YE/WH) open, short to ground or voltage
- Circuit 1356 (LG/VT) open, short to ground or voltage
- Circuit 1357 (LB/YE) open or short to voltage
- Circuit 1843 (BK/OG) open or short to voltage
- Fuel pump module
- Fuel level sensor
- Fuel tank transfer tube
- Fuel lines
- Fuel tank
- Instrument cluster