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Knock Sensors, Checking



Knock Sensors, Checking







Special tools and equipment
- VAG 1526A
- VAG 1594A
- VAG 1598/31

NOTE:
- The knock sensor (KS) 1 -G61- and engine coolant temperature (ECT) sensor -G62- cannot be tested by themselves electrically.
- Use only gold-plated terminals when repairing the cable connectors for the knock sensors.
- To ensure that the knock sensors function properly it is important to keep to the specified tightening torque of 20 Nm.
- Check connector between knock sensor and wiring harness for corrosion.

Testing knock sensor wiring
- Disconnect connector of relevant knock sensor.







- Test for short between all three terminals in knock sensor connector (terminals 1+2, 1+3, 2+3).
- Specified value: Infinity Ohms (no continuity) - the wiring must not be connected to each other.
- If there is a connection between terminals, install a new knock sensor.

If no malfunction is found:

Checking wiring from knock sensors to engine control module
- Connect test box VAG 1598/31 to wiring harness for engine control module; do not connect engine control module. Wiring and Component Testing Using VAG1598/31 Test Box
- Check for open circuit and short to ground/positive or ground in following wiring connections:







- Knock sensor (KS) 1 -G61 - (Bank 1)

Connector Test box VAG 1598/31
terminal Socket

1 (signal) 106
2 (ground) 99
3 (screening) 108

- Knock Sensor (KS) 2 -G66- (Bank 2)

Connector Test box VAG 1598/31
terminal Socket

1 (signal) 107
2 (ground) 99
3 (screening) 108

- Repair any open/short circuit as necessary.