Knock Sensor 2 -G66-, Checking
General Description
The Knock Sensor 2 -G66- is a tuned accelerometer on the engine which converts engine vibration to an electrical signal. The Engine Control Module -J623- uses this signal to determine the presence of engine knock and to retard spark timing.
Special tools and workshop equipment required
- Multimeter.
- Wiring Diagram.
- Scan Tool.
Test Procedure
NOTE:
Prior to beginning the test procedure, make sure to check the items listed below:
Poor fuel quality
Ignition timing malfunction
Loose components on the engine block
Engine temperature must be in the normal range
| Step |
Procedure |
Result / Action to Take |
| 1 |
- PERFORM: Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK
.
-- Was Complaint verified? |
-- YES:
-- NO:
- GATHER more information from customer about the complaint.
|
| 2 |
- IGNITION: OFF.
- CONNECT: Scan tool.
- START: Engine and let Idle.
- CHECK: The ignition advance timing value.
- TAP: Near the Knock Sensor 2 -G66- area and monitor for any fluctuations in the ignition timing advance value.
- IGNITION: OFF.
- SPECIFIED VALUE: 1 - 10 degrees of ignition timing fluctuation.
-- Was Value obtained? |
-- YES:
- Condition may be intermittent.
- PERFORM: Visual Inspection of wiring and component.
- CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals.
- REPAIR: Faulty wiring or connector.
- GO TO: Step 4.
-- NO:
|
| 3 |
- REMOVE: Engine Control Module - J623-. Refer to appropriate Service Information.
- CHECK: Knock Sensor 2 -G66- harness connector terminal 1 to the Engine Control Module - J623- harness connector T60 / 9 for resistance.
- CHECK: Knock Sensor 2 -G66- harness connector terminal 2 to the Engine Control Module - J623- harness connector T60 / 24 for resistance.
- CHECK: Knock Sensor 2 -G66- harness connector terminal 3 to the Engine Control Module - J623- harness connector T60 / 52 for resistance.
- SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Were Values obtained? |
-- YES:
- TIP: The Knock Sensor 2 -G66- may fail under loaded operation; please swap a known good Knock Sensor 2 -G66- prior to continuing to the next step.
- GO TO: Step 4.
-- NO:
- PERFORM: Visual Inspection of wiring and component.
- CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals.
- REPAIR: Faulty wiring or connector.
- GO TO: Step 4.
|
| 4 |
- Final Procedure
- Perform a road test to verify repair.
-- Does the original DTC return? |
-- YES:
- CHECK: Engine Control Module -J623- harness connector for any damaged, pushed-out pins.
- REPAIR: As necessary.
- If all electrical connections are OK:
- REPLACE: Engine Control Module -J623-. Refer to appropriate Service Information.
- Clear the DTC's. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY
.
- Repair is complete. Generate Readiness Code. Refer to READINESS CODE
.
- Return vehicle to Customer.
-- NO:
- Perform the diagnostic procedure for any DTC's.
- If no DTC's return, the repair is complete.
- Return vehicle to customer.
|