Knock Sensor (KS) 2 G66, checking

WARNING: This page is about a different car, the 2006 Audi A4, 2005 Audi A4, 2004 Audi A4, 2003 Audi A4, and 2002 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Use only gold-plated terminals when servicing terminals in the electrical harness connectors of the Knock Sensor (KS) 2 G66.

Special tools, testers and auxiliary items required

Multimeter.
Wiring diagram.

Test requirements

The mounting bolt of Knock Sensor (KS) 2 G66 tightened to 20 Nm.
The Motronic Engine Control Module (ECM) J220 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 .

Start diagnosis

Fig 1: Location Of Knock Sensor (KS) 2 -G66-

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Disconnect the Knock Sensor (KS) 2 G66 electrical harness connector - arrow -.

Checking internal resistance

Fig 2: Identifying Engine Speed (RPM) Sensor G28 Terminals

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Using a Multimeter, check the Knock Sensor (KS) 2 G66 terminals 1 to 2 for an internal short.

Specified value: ∞ (Infinity).

If the specified value was not obtained:

Replace the Knock Sensor (KS) 2 G66.

If the specified value was obtained:

Checking wiring

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

Install the test box VAG1598/31. Refer to 24 MULTIPORT FUEL INJECTION (MFI) .

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

Remove the Motronic Engine Control Module (ECM) J220. Refer to → Motronic Engine Control Module (ECM) J220, Replacing .

Fig 3: Identifying 3-Pin Connector Terminals 1 & 3

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Using a Multimeter, Check the Knock Sensor (KS) 2 G66 electrical harness connector to the Motronic Engine Control Module (ECM) J220 electrical harness connector for resistance.

Knock Sensor (KS) 2 G66 electrical harness connector terminals	Motronic Engine Control Module (ECM) J220 electrical harness connector terminals or test box sockets
1	107
2	99
3	108

Specified value: 1.5 Ω 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 electrical harness connector for damage, corrosion, loose 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 (KS) 2 G66.
Erase the DTC memory. Refer to → Diagnostic Mode 04 - Reset/Delete Diagnostic Data .
Perform a road test to verify repair.

If the DTC does not return:

Repair complete, Generate readiness code. Refer to → Readiness Code .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was not OK:

Replace the Motronic Engine Control Module (ECM) J220. Refer to → Motronic Engine Control Module (ECM) J220, Replacing .
Assembly is performed in the reverse of the removal.

Final procedures

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

Check the DTC memory.
If necessary, erase the DTC memory. Refer to Diagnostic Mode 04 - Reset/Delete Diagnostic Data .
If the DTC memory was erased, generate readiness code. Refer to Readiness Code Description .

End of diagnosis