Knock Sensor: Testing and Inspection
NOTES:- Knock sensors can not be checked electrically, check DTC memory.
- Use connector insertion tool 3247 for knock sensor removing and installing.
- It is important that exact knock sensor tightening torque of 20 Nm (15 ft lb) be maintained to make sure that there is proper knock sensor function.
- Visually check the knock sensor connector for corrosion.
- When repairing or replacing knock sensor connector terminals, ONLY replace with gold plated terminals.
CHECKING KNOCK SENSOR WIRING:
- Disconnect knock sensor harness connectors in engine compartment.
- Check all three terminals in knock sensor harness connector for shorting to each other.
Wires must not be short circuited to each other.
If there is a short circuit:
- Replace knock sensor.
CHECKING WIRING BETWEEN KNOCK SENSOR AND ECM:
- Connect VAG 1598/19 test box to ECM harness connector.
- Check wiring for continuity or short between knock sensor and ECM using wiring diagram.
Terminal Assignments (inside connector)
1 - Ground (GND) wire
2 - Signal wire
3 - Shield
KNOCK SENSOR (KS) 1 -G61-:
- Check signal wire for continuity between harness connector terminal 2 (in engine compartment) and test box socket A13.
Specified Value: max. 1 ohm.
- Check Ground (GND) wire for continuity between harness connector terminal 1 and test box socket A14.
Specified Value: max. 1 ohm.
- Check shielding for continuity between harness connector terminal 3 (in engine compartment) and engine Ground.
Specified Value: max. 1 ohm.
If specified values are not obtained:
- Repair open or short circuit.
KNOCK SENSOR (KS) 2 -G66-:
- Check signal wire for continuity between harness connector terminal 2 (in engine compartment) and test box socket A15.
Specified Value: max. 1 ohm.
- Check Ground (GND) wire for continuity between harness connector terminal 1 and test box socket A14.
Specified Value: max. 1 ohm.
- Check shielding for continuity between harness connector terminal 3 (in engine compartment) and engine Ground.
Specified Value: max. 1 ohm.
If the specified values are not obtained:
- Eliminate open or short circuit in wiring.
KNOCK SENSOR 1 (bank 1):
Knock Sensor ECM Connector A or
Terminal Number Engine Ground (GND)
1 (Ground) A14
2 (Signal) A13
3 (Shield) Engine Ground (GND)
KNOCK SENSOR 2 (bank 2):
Knock Sensor ECM Connector A or
Terminal Number Engine Ground (GND)
1 (Ground) A14
2 (Signal) A15
3 (Shield) Engine Ground (GND)