With Generic Scan Tool
Check Knock Sensors
- Contact surfaces between knock sensor and cylinder block must be free of corrosion, dirt and grease.
- For the Knock Sensors to function properly, it is important for tightening torque to be exactly 20 Nm.
- Use only gold-plated terminals when servicing terminals in harness connector of knock sensors.
Recommended special tools and equipment
- VAG1526 multimeter or VAG1715 multimeter
- VAG1594 connector test kit
- Wiring diagram
Test requirements
- Knock sensor securing bolt tightened to 20 Nm.
- On Board Diagnostic (OBD) must have recognized a malfunction at one or both of the Knock Sensors (KS).
- Ignition switched off.
Checking resistance values of knock sensors
Vehicles with engine code AWD
- Disconnect the 3-pin harness connector for Knock Sensor (KS) 1 -G61- (-1-).
- Measure resistance between terminals 1 + 2, 1 + 3, and 2 + 3 at connectors to knock sensors.
Specified value: Infinite Ohms
- Disconnect the 3-pin harness connector for Knock Sensor (KS) 2 -G66- (-1-).
- Measure resistance between terminals 1 + 2, 1 + 3, and 2 + 3 at connectors to knock sensors.
Specified value: Infinite Ohms
If specified value is not obtained:
- Replace the respective knock sensor:
- Knock Sensor (KS) 1 -G61-, item 7,
- Knock Sensor (KS) 2 -G66-, item 8.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes
Vehicles with engine code AWP, AWW
- Disconnect 2-pin harness connector to Knock Sensor (KS) 1 -G61-(-1-) and/or 2-pin harness connector to Knock Sensor (KS) 2 -G66-(-2-).
- Measure resistance between terminals 1 + 2 at connectors to knock sensors.
Specified value: Infinite Ohms
If specified value is not obtained:
- Replace the respective knock sensor:
- Knock Sensor (KS) 1 -G61-, item 12,
- Knock Sensor (KS) 2 -G66-, item 13.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes
Continuation for all vehicles
If specified value is obtained:
- Check wires.
Checking wiring
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test
Vehicles with engine code AWD
- Check wiring between test box and 3-pin connector for open circuit according to wiring diagram.
Terminal 1 + socket 106 (-G61-) / 107 (-G66-)
Terminal 2 + socket 99 (-G61-) / 99 (-G66-)
Terminal 3 + socket 108 (-G61-) / 108 (-G66-)
Wire resistance: max: 1.5 Ohms
- Also check wires for short circuit to each other.
Specified value: Infinite Ohms
If specified value is not obtained:
- Replace the respective knock sensor:
- Knock Sensor (KS) 1 -G61-, item 7,
- Knock Sensor (KS) 2 -G66-, item 8.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes
Vehicles with engine code AWP, AWW
- Check wires between test box and 2-pin connector for open circuit according to wiring diagram.
Terminal 1 + socket 106 (-G61-) / 107 (-G66-)
Terminal 2 + socket 99 (-G61-) / 99 (-G66-)
Wire resistance: max: 1.5 Ohms
- Also check wires for short circuit to each other.
Specified value: Infinite Ohms
If specified value is not obtained:
- Replace the respective knock sensor:
Knock Sensor (KS) 1 -G61-, item 12,
Knock Sensor (KS) 2 -G66-, item 13.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data.Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes