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Knock Sensor 3, Checking






Knock Sensor 3, Checking

The following procedure is used to diagnose Knock Sensor 3 (G198) which is controlled by Engine Control Module (ECM) 2 (J624).

Special tools, testers and auxiliary items required

Multimeter.

Wiring diagram.

Test requirements

The mounting bolt of Knock Sensor 3 (G198) tightened to 20 Nm.

The Engine Control Module (ECM) 2 (J624) fuses OK.

Battery voltage at least 12.5 volts.

All electrical consumers such as, lights and rear window defroster, switched off.

Vehicles with automatic transmission, shift selector lever into position " P" or "N".

A/C switched off.

Ground (GND) connections between engine/transmission/chassis OK.

Ignition switched off.

Test Procedure

- Perform a preliminary check to verify the customers complaint. Refer to => [ Preliminary Check ] Preliminary Check

- Remove the front engine cover - 1 -.





- Disconnect the Knock Sensor 3 (G198) electrical harness connector- 8 -.





Checking internal resistance

- Using a Multimeter, check the Knock Sensor 3 (G198) terminals 1 to 2 for an internal short.





Specified value: infinite (Infinity).

If the specified value was not obtained:

- Replace Knock Sensor 3 (G198). Refer to appropriate repair information.

If the specified value was obtained:

Checking wiring

If the manufacturers test box is being used, perform the following step.

- Install the test box. Refer to appropriate repair information.

If the manufacturers test box is not being used, perform the following step.

- Remove the Engine Control Module (ECM) 2 (J624). Refer to appropriate repair information.

- Using a Multimeter, check the Knock Sensor 3 (G198) electrical harness connector to the Engine Control Module (ECM) 2 (J624) electrical harness connector T60a for an open circuit.









Specified value: 1.5 ohms Max.

If the specified value was not obtained:

- Check the wiring connection for an open circuit, short circuit to Battery (+) or Ground (GND).

- Check the wiring connection for damage, corrosion, lose or broken terminals.

- If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring and the resistance was not OK:

- Replace Knock Sensor 3 (G198). Refer to appropriate repair information.

If no malfunction is found in the wiring and the resistance was OK:

- Replace the Engine Control Module (ECM) 2 (J624). Refer to appropriate repair information.

- Assembly is performed in the reverse order of removal.

Final procedures

After repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 0A.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 0A.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.