Signal Circuit Inspection

Check voltage
1. Key "OFF".
2. Disconnect Knock sensor connector.
3. Key "ON".
4. Measure the voltage between terminal 1 of knock sensor harness connector and chassis ground.
5. Measure the voltage between terminal 2 of knock sensor harness connector and chassis ground.
  1. Specification : Approx 2.4V
    
    Fig 1: Measuring Voltage Between Terminal 1 And 2 Of Knock Sensor Harness Connector And Chassis Ground
    Courtesy of KIA MOTORS AMERICA, INC.
6. Is the measured voltage within specification?
  YES
  1. Go to "COMPONENT INSPECTION " procedure.
  NO
  1. Go to " 2 Check resistance" procedure.
Check resistance
1. Key "OFF".
2. Disconnect Knock sensor connector and ECM connector.
3. Measure the resistance between terminal 1 of knock sensor harness connector and 30 of PCM harness connector. [A/T]
  Measure the resistance between terminal 1 of knock sensor harness connector and 32 of ECM harness connector. [M/T]
4. Measure the resistance between terminal 2 of knock sensor harness connector and 15 of PCM harness connector. [A/T]
  Measure the resistance between terminal 2 of knock sensor harness connector and 11 of ECM harness connector. [M/T]
  1. Specification : Below Approx 1Ω
    
    Fig 2: Measuring Resistance Between Terminal 2 Of Knock Sensor Harness Connector And 11 Of ECM Harness Connector
    Courtesy of KIA MOTORS AMERICA, INC.
5. Is the measured resistance within specifications?
  YES
  1. Repair Short to ground in signal circuit and then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.
  NO
  1. Repair Open in signal circuit and then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.