SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSAUDI2005A4 QUATTRO, 4D SEDAN, 3.2 GREPAIR AND DIAGNOSISENGINE PERFORMANCETUNE-UP3.2L - GENERIC SCAN TOOL, ENGINE CODE: BKH28 - IGNITION/GLOW PLUG SYSTEMIGNITION SYSTEM, SERVICINGKNOCK SENSOR (KS) , CHECKING
2005 Audi A4 Quattro, 4D Sedan, 3.2 G

Knock Sensor (KS) , Checking

2005 Audi A4 Quattro, 4D Sedan, 3.2 GSECTION Knock Sensor (KS) , Checking

The following procedure is used to check Knock Sensor (KS) 1 G61 and Knock Sensor (KS) 2 G66.

Special tools, testers and auxiliary items required 

  • Multimeter.
  • Wiring diagram.
NOTE:
  • Cylinders 1, 2, and 3 (bank 1) are monitored by Knock sensor (KS) 1 -G61-. Cylinders 4, 5, and 6 (bank 2) are monitored by Knock sensor (KS) 2 -G66-.
  • Knock sensors themselves cannot be checked electrically.
  • When servicing terminals in the harness connector of knock sensors, use only gold-plated terminals.
  • For the knock sensors to function properly, it is important that the tightening torque be exactly 20 Nm.
  • Contact surfaces between Knock Sensor (KS) 1 G61 and Knock Sensor (KS) 2 G66 and cylinder block must be free of corrosion, dirt and grease.

Test requirements 

  • The mounting bolt of Knock Sensor (KS) 1 G61/Knock Sensor (KS) 2 G66 tightened to 20 Nm.
  • The Engine Control Module (ECM) J623 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 → General Diagnosis .

Start diagnosis 

Fig 1: Removing/Installing Rear Engine Cover
GW00017835Courtesy of VOLKSWAGEN UNITED STATES, INC.
  • Remove the rear engine cover - arrows  -.

Checking knock sensor and wiring 

NOTE:
  • The knock sensor electrical connectors can be identified by color. Knock Sensor (KS) 1 -G61- (Bank 1) is green. Knock Sensor (KS) 2 -G66- (Bank 2) is gray.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.