Control Circuit Inspection

Check for Open in Control Harness

1. Ignition "OFF"
2. Disconnect HO2S and ECM connectors.
3. Measure resistance between terminals 2 of the HO2S heater harness connector and 40 of the ECM harness connector.
   1. Specification: Approx. 0Ω
      Fig 1: Measuring Resistance Between Terminals 2 Of HO2S Heater Harness Connector And 40 Of ECM Harness Connector

      
4. Is resistance within the specification?

   YES

   1. Go to next step as below.

   NO

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

Check for Short to Battery in Control Circuit

1. Reconnect the ECM connector.
2. Ignition "ON" & Engine "OFF".
3. Measure voltage between terminal 2 of the HO2S heater harness connector and chassis ground.
   1. Specification: Approx 0V
      Fig 2: Measuring Voltage Between Terminal 2 Of HO2S Heater Harness Connector And Chassis Ground

      
4. Is voltage within the specification?

   YES

   1. Go to "COMPONENT INSPECTION " procedure.

   NO

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