P0326

P0326
Knock Sensor 1 Circuit - Range / Performance
Knock Sensor 1 - Signal implausible

P0331
Knock Sensor 2 Circuit - Range / Performance
Knock Sensor 2 - Signal implausible

P1386
Knock Control - Malfunction
Knock Control Test Pulse - Signal implausible

Function
The Knock Control is designed to detect knocking combustion and to adjust the ignition timing toward late. When no further knocking occurs, the ignition timing is advanced again gradually to the specified value. Because of the engine design (boxer engine), 2 knock sensors are needed.

Knock Sensor 1 cylinders 1 to 3
Knock Sensor 2 cylinders 4 to 6

Diagnostic conditions
Engine speed higher than 3600 1/min





Wiring Diagram.









Diagnostic procedure
Check wiring from ECM to knock sensors for continuity.
1. Remove knock sensor connectors.
2. Remove ECM connector.
3. Connect ohmmeter to ECM connector, pin 70 and to knock sensor connector 1, pin 1. Specified value: 0 - 5 ohms.
4. Connect ohmmeter to ECM connector, pin 40 and to knock sensor connector 2, pin 1. Specified value: 0 - 5 ohms.
5. Connect ohmmeter to ECM connector, pin 71 and to knock sensor connector 1, pin 2. Specified value: 0 - 5 ohms.
6. Connect ohmmeter to ECM connector, pin 71 and to knock sensor connector. 2, pin 2. Specified value: 0 - 5 ohms.
7. Connect ohmmeter to knock sensor connector 1, pin 3 and to ground. Specified value: 0 - 5 ohms.
8. Connect ohmmeter to knock sensor connector 2, pin 3 and to ground. Specified value: 0 - 5 ohms.

- If the meter reads infinite resistance at points 3 to 8, check wiring harness for chafing and pinching damage.

Check wiring from ECM to knock sensors for short to ground.
1. Remove connectors for knock sensors.
2. Remove ECM connector.
3. Connect ohmmeter to ECM connector, pin 70 and ground. Specified value: ohms
4. Connect ohmmeter to ECM connector, pin 40 and ground. Specified value: ohms

- If the meter reads resistance of 0 - 5 ohms at points 3 and 4, check wiring harness for chafing and pinching damage.

Check wiring from ECM to knock sensors for short to B+.
1. Remove knock sensor connectors.
2. Remove ECM connector.
3. Connect voltmeter to ECM connector, pin 70 and ground. Specified value: 0 Volt
4. Connect voltmeter to ECM connector, pin 40 and ground. Specified value: 0 Volt
5. Connect voltmeter to ECM connector, pin 71 and ground. Specified value: 0 Volt.

- If meter reads battery voltage at points 3 to 5, check wiring harness for chafing and pinching damage.