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Home >> Audi >> 2009 >> A5 Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> Engine Control Systems >> GENERIC SCAN TOOL [CALA] (2 Of 2) (COUPE) >> Generic Scan Tool >> Diagnosis And Testing >> Diagnostic Procedures >> Knock Sensor 1 - G61-, Checking >> Notes
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Knock Sensor 1 - G61-, Checking: Notes

General Description 

The Knock Sensor 1 -G61- 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, If Necessary.

Special Tools And Workshop Equipment Required 

Test Requirements 

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
  • 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.
  • IGNITION: OFF.
  • CONNECT: Scan tool.
  • START: Engine and let Idle.
  • CHECK: The ignition advance timing value.
  • TAP: Near the Knock Sensor 1 -G61- 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 Knock Sensor 1 - G61-, CHECKING - 4 .
-- NO:
  • REMOVE: Engine Control Module - J623-. Refer to appropriate service information.
  • DISCONNECT: Knock Sensor 1 -G61- harness connector.
  • CHECK: Knock Sensor 1 -G61- harness connector terminal 1 to the Engine Control Module - J623- harness connector T60 / 58 for resistance.
  • CHECK: Knock Sensor 1 -G61- harness connector terminal 2 to the Engine Control Module - J623- harness connector T60 / 57 for resistance.
  • CHECK: Knock Sensor 1 -G61- harness connector terminal 3 to the Engine Control Module - J623- harness connector T60 / 42 for resistance.
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Were Values obtained?
-- YES:
  • TIP: The Knock Sensor 1 -G61- may fail under loaded operation; please swap a known good Knock Sensor 1 -G61- prior to continuing to the next step.
  • GO TO: Step 4 Knock Sensor 1 - G61-, CHECKING - 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 Knock Sensor 1 - G61-, CHECKING - 4 .
Refer To The Final Procedure Below;