Component Inspection

1. Measure resistance between signal terminal and ground terminal of the sensor connector (Component side).

   Specification  : Approx. 5MΩ at 20°C (68°F)

   Fig 1: Measuring Resistance Between Signal Terminal & Ground Terminal Of Sensor Connector

   Courtesy of HYUNDAI MOTOR CO.

1. Remove knock sensor from vehicle and secure (across mounting boss) in a shop vise.
2. Set up an oscilloscope as follows:

   Channel A (+): Signal terminal, (-): Ground terminal

3. 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

   Fig 2: Inspecting Output Signal

   Courtesy of HYUNDAI MOTOR CO.

1. Check the installation torque of the knock sensor.

   Specification  : Approx. 16 ~ 28N.m (160~250 kg.cm, 11.8~18.4 lb.ft)

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