Knock Sensor: Testing and Inspection

KNOCK SENSOR

OPERATION
The knock sensor converts cylinder block vibrations due to knocking into voltage according to the strength of the vibrations and inputs it to the engine control module. The engine control module controls the delay in spark timing according to this signal.

TROUBLESHOOTING HINTS
When knocking occurs when driving at maximum load, the following troubles, other than the knock sensor, can be inferred.
1. Incorrect spark plug heat rating
2. Incorrect gasoline
3. Incorrect standard spark timing adjustment

HARNESS INSPECTION





STEP 1. Check for an open circuit or a short-circuit to ground between the knock sensor and the engine control module.
- Knock sensor connector: Disconnected
- Engine control module connector: Disconnected

OK: GO TO STEP 2
NG: Repair the harness. (A1 - 78)





STEP 2. Check for continuity in the ground circuit.
- Knock sensor connector: Disconnected

OK: STOP
NG: Repair the harness. (A2 - Ground)