Component resistance inspection
Measure resistance between terminals 1 and 2 of the sensor connector(Component side)
Specification : Approx. 5MΩ at 20°C(68°F)
Output signal inspection
Remove knock sensor from vehicle and secure (across mounting boss) in a shop vise.
Set up an oscilloscope as follows :
Channel A (+): terminal 1 (-): terminal 2
Rap on vise with a ball peen hammer while monitoring oscilloscope screen (there should be a spike of less than 1 volt with each hammer strike).
Specification : knock sensor send a voltage spike with hammer strikes
Installation torque inspection
Check the installation torque of the knock sensor.
Specification : Approx. 16 ~ 28N·m(160~250 kg·cm,11.8~18.4 lb·ft)
Has a problem been found?
YES
▶ Check knock sensor for contamination, deterioration, or damage. Substitute with a known-good sensor and check for proper operation. If the problem is corrected, replace sensor and then go to "Verification of Vehicle Repair" procedure
NO
▶ Check for poor connection between ECM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection. Repair as necessary and go to "Verification of Vehicle Repair" procedure