Signal from fuel sending unit, checking
If the fuel gauge is malfunctioning, check for signal at the instrument cluster.
- Connect VAS5051 tester or VAG1551 scan tool. See VAS 5051 VEHICLE DIAGNOSTIC, MEASURING AND INFORMATION SYSTEM OR VAG1551 SCAN TOOL, CONNECTING AND SELECTING FUNCTIONS .
- Read memory. See READ MEASURING VALUE BLOCK (SCAN TOOL FUNCTION 08) .
- Select display group 2.
- If the display in the diagnostic unit V.A.G 1551 does display the fuel level but not the instrument cluster, replace the instrument cluster.
- If no fuel level is displayed in the diagnostics unit V.A.G 1551, check the signal at the multi-pin connector at the instrument cluster.
- Instrument cluster removal. See INSTRUMENT CLUSTER, REMOVING AND INSTALLING .
- Connect the test box V.A.G 1598 with the adapter V.A.G 1598/25 to the 32-pin connector.
- Use the multi meter V.A.G 1526 between terminal 5 and terminal 7 (sensor ground) and measure the resistance.
Base value:
Vehicles with front wheel drive:
SENDER FOR FUEL GAUGE -G- RESISTANCE (VEHICLES WITH FRONT WHEEL DRIVE)
| Sender | Tank full | Tank empty |
|---|---|---|
| Sender for fuel gauge -G- | 270 ohm | 70 ohm |
Vehicles with all wheel drive (Quattro) (Production date up to approx. 02.99):
SENDER FOR FUEL GAUGE RESISTANCE (VEHICLES WITH ALL WHEEL DRIVE, PRODUCTION DATE UP TO 02.99)
| Sender | Tank full | Tank empty | ||
|---|---|---|---|---|
| Sender for fuel gauge -G- | approx. 70 ohm | approx. 10 ohm (1) | ||
| Sender II for fuel gauge -G169- | approx. 118.5 ohm | approx. 20 ohm | ||
| Sender III for fuel gauge -G237- | approx. 81.5 ohm | approx. 30 ohm | ||
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Vehicles with Quattro drive (production date approx. from 02.99 on):
SENDER FOR FUEL GAUGE RESISTANCE (VEHICLES WITH QUATTRO DRIVE, PRODUCTION DATE FROM 02.99 ON)
| Sender | Tank full | Tank empty | ||
|---|---|---|---|---|
| Sender for fuel gauge -G- | approx. 70 ohm | approx. 10 ohm(1) | ||
| Sender II for fuel gauge -G169- | approx. 108.5 ohm | approx. 20 ohm | ||
| Sender III for fuel gauge -G237- | approx. 91.5 ohm | approx. 30 ohm | ||
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- If the base value is not achieved, check the harness connectors between the instrument cluster and the sender for the fuel gauge -G- (Front drive/Quattro) or -G169- (Quattro) or -G237- (Quattro) according to wiring diagram
See appropriate System Wiring Diagram article.
- If no open or short circuit is detected, check the sending unit -G- (Front drive/Quattro) or -G169- (Quattro) or -G237- (Quattro).
- Check sender for fuel gauge.
- If the base values are not achieved, the instrument cluster is defective and must be replaced. See INSTRUMENT CLUSTER, REMOVING AND INSTALLING .