Signal Circuit Inspection

■ Check for short to ground in signal circuit 

1. Measure resistance between signal terminal of the sensor harness connector and chassis ground.

   Specification:  Infinite

   Fig 1: Measuring Resistance Between Signal Terminal Of Sensor Harness Connector And Chassis Ground

   Courtesy of HYUNDAI MOTOR AMERICA
2. Is resistance within the specification?

   YES 

   • Go to next step as below.

   NO 

   • Check signal circuit for short to ground. Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.

■ Check for short to power in signal circuit 

1. Disconnect PCM connector.
2. Ignition "ON" & Engine "OFF"
3. Measure voltage between signal terminal of sensor harness connector and chassis ground.

   Specification:  Approx. 0V

   Fig 2: Measuring Voltage Between Signal Terminal Of Sensor Harness Connector And Chassis Ground

   Courtesy of HYUNDAI MOTOR AMERICA
4. Is voltage within the specification?

   YES 

   • Go to next step as below.

   NO 

   • Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.

■ Check for open in signal harness 

1. Ignition "OFF"
2. Measure resistance between signal terminal of sensor harness connector and Knock signal terminal of the PCM harness connector.

   Specification:  Approx. 0Ω

   Fig 3: Measuring Resistance Between Signal Terminal Of Sensor Harness Connector And Knock Signal Terminal Of PCM Harness Connector

   Courtesy of HYUNDAI MOTOR AMERICA
3. Is resistance within the specification?

   YES 

   • Go to next step as below.

   NO 

   • Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.