Knock Sensors, Checking
Knock Sensors, Checking
NOTE:
- 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
- V.A.G 1526 multimeter or V.A.G 1715 multimeter
- V.A.G 1594 connector test kit
- Wiring diagram
Requirements
- Knock sensor mounting bolt tightened to 20 Nm.
- Ignition switched off.
Checking resistances and wires (vehicles with engine code AEG)
- Disconnect 2-pin connectors from knock sensors.
1. Knock Sensor (KS) 1 -G61-
2. Knock Sensor (KS) 2 -G66-
NOTE: Before disconnecting harness connectors, mark allocation to component.
- Measure resistance between terminals 1 + 2 at connectors to knock sensors.
Specified value: Infinite Ohms
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test
- Check wires between test box and 2-pin connector to Engine Control Module (ECM) for open circuit according to wiring diagram.
Wire resistance: max. 1.5 Ohms
- Check wires for short circuit to each other.
Specified value: Infinite Ohms
If resistances and wires are OK.
- Replace the respective knock sensor:
- Knock Sensor (KS) 1 -G61-.
- Knock Sensor (KS) 2 -G66-.
- 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.
Checking resistances and wires (vehicles with engine code AVH, AZG, BBW, BEV)
- Disconnect 2-pin connectors from knock sensors.
1. Knock Sensor (KS) 1 -G61-
2. Knock Sensor (KS) 2 -G66-
NOTE: Before disconnecting harness connectors, mark allocation to component.
- Measure resistance between terminals 1 + 2 at connectors to knock sensors.
Specified value: Infinite Ohms
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test
- Check wires between test box and 2-pin connector to Engine Control Module (ECM) for open circuit according to wiring diagram.
Wire resistance: max. 1.5 Ohms
- Check wires for short circuit to each other.
Specified value: Infinite Ohms
If resistances and wires are OK.
- Replace respective knock sensor:
Vehicles with engine code AVH, AZG, BEV:
- Knock Sensor (KS) 1 -G61-.
- Knock Sensor (KS) 2 -G66-.
Vehicles with engine code BBW.
- Knock Sensor (KS) 1 -G61-.
- Knock Sensor (KS) 2 -G66-.
- 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.