Fuel Gauge: Testing and Inspection

Required special tools and test equipment
- VAG1551 or VAG1552 Scan Tool (ST)
- VAG1598/25 test box
- Multimeter US1119 (Fluke 83 or equivalent)

Checking
If the fuel gauge in the instrument cluster shows an incorrect reading, first check whether the signal is received by the instrument cluster.

- Connect VAG1551/VAG1552 Scan Tool (ST) and press buttons -1- and -7- to insert "Instrument Cluster" address word 17 (with ignition switched on). Testing and Inspection

Indicated on display

Rapid data transfer Q
17 - Instrument Cluster

- Press -Q- button to confirm input.

Indicated on display (after approximately 5 seconds)

4B0919930BC5INSTRCLUSTUN4 D13->
coding 07262 WSC 06812

- Press -> button.

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -8- to select "Read Measuring Value Block" function 08, and press -Q- button to confirm input.

Indicated on display

Rapid data transfer Q
08 - Read Measuring Value Block

Indicated on display

Read Measuring Value Block HELP
Input display group number XXX

- Press buttons -0-, -0- and -2- to input display group number 002, and press -Q- button to confirm input.

Indicated on display (1-4 = display fields)

Read Measuring Value Block 2 ->
1 2 3 4

If the fuel level is displayed in display field 2 on the scan tool, the instrument cluster is faulty and must be replaced.
If the fuel level is not displayed in display field 2:
- Check signal to multi-pin connector at instrument cluster.
- Press -> button.

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -6- to select "End Output" function 06.

Indicated on display

Rapid data transfer Q
06 - End Output

- Press -Q- button to confirm input.

- Connect VAG1598/25 test box to blue 32-pin connector.
- Using multimeter US1119 (Fluke 83 or equivalent), measure resistance between terminals 5, (fuel gauge sender) and 7, (signal Ground).

Specifications:
- Fuel tank full: approx. 270 ohms
- Fuel tank half full: approx. 170 ohms
- Fuel tank on reserve: approx. 96 ohms

If specifications are not obtained:
- Check wiring per wiring diagram.
- If wiring is faulty, repair wiring.

If wiring is OK:
- Remove sender from tank.
- Test sender.

If specifications are still not obtained:
- Replace sender.