SEAT Workshop Service and Repair Manuals

Verification process –  Before checking, make sure that the sender is fitted and correctly secured.

–  By the underneath of the vehicle, disconnect the grey triple connection-arrow- to the engine speed sender.

–  Measure the resistance between contacts 2+3 of connector to sender. Specification: 730 … 1000 Ω.   Note! The resistance value of the engine speed sender refers to a temperature of 20 °C. The resistance rises when the temperature increases. If the ideal value is not measured: –  Replace engine speed sender -G28-. If the specification is obtained:

–  Adjust the multimeter to measure resistance and connect between contacts 2 and 1 (screening), as well as between contacts 3 and 1 (screening). Specification: ∞Ω (no passage). If the ideal value is not measured: –  Replace engine speed sender -G28-. If the specification is obtained:

–  Connect test box -V.A.G 1598/31- to control unit wiring harness, without connecting the engine control unit (for BBX engines use the tester -V.A.G 1598/22-) → Chapter.

–  Check wiring between test box and 3-pin connector for open circuit or closed circuit to earth or positive:

3-pin connector, contact	Test box -V.A.G 1598/31-, female connector	Test box -V.A.G 1598/22-, female connector
1 (screening)	108	54
2 (earth)	90	67
3 (signal)	82	53
Specification: 1.5 Ω max.

–  Additionally check wires for short to one another. If no wiring fault is detected: –  Replace engine control unit: → VAS 5051; Vehicle self-diagnosis.