SEAT Workshop Service and Repair Manuals

Engine speed sender -G28-: checking

The engine speed sender -G28- is a speed and reference mark sender. If there is no speed signal, the engine will not start. If the speed signal fails when the engine is running, the engine stalls.

Fitting location → Item

Special tools and workshop equipment required

t	Hand multimeter -V.A.G 1526 A- or -V.A.G 1715-

t	auxiliary measuring set -V.A.G 1594 A- or -V.A.G 1594 C-

t	Test box -V.A.G 1598/22-

t	Current flow diagrams

Checking conditions l  Battery voltage at least 11.5 V Test sequence

–  Pull off 3-pin connector -2- to the engine speed sender

–  Measure the supply voltage with the multimeter and the auxiliary cables of -V.A.G 1594 A- or -V.A.G 1594 C- between:

Connector, contact	Connector, contact
1 (positive)	3 (earth)
Switch ignition on
Specification: 4.5 V min.

–  Switch ignition off. If no voltage is present

–  Connect test box -V.A.G 1598/22- to control unit wiring harness.

–  Check the wiring between test box and 3-pin connector for open circuit using current flow diagram.

Connector, contact	Test box -V.A.G 1598/22-, socket
1	62
2	53
3	67
Specification: 1.5 Ω max.

–  Additionally, check wires for shorts to one another, to vehicle earth or to battery positive.    Specification: ∞ Ω

If no wiring fault is detected and voltage was present between contacts 1 + 3: –  Replace engine speed sender -G28- → Item. If no wiring fault is detected and voltage was not present between contacts 1 + 3: –  Renew engine control unit → VAS 5051; Vehicle self-diagnosis.