Circuit/System Testing
WARNING: This page is about a different variant/trim than selected.
- Ignition OFF, disconnect the harness connector at the appropriate B52 Heated Oxygen Sensor, ignition ON.
- Verify that a test lamp illuminates between the ignition voltage circuit terminal 2 and ground.
- If the test lamp does not illuminate and the circuit fuse is good
- Ignition/Vehicle - Off & Remove - Test lamp
- Test for less than 2 Ω in the ignition circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
- If the test lamp does not illuminate and the circuit fuse is open
- Ignition/Vehicle - Off & Remove - Test lamp
- Test for infinite resistance between the ignition circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance, test all components connected to the fuse and replace as necessary.
- Go to next step: If the test lamp illuminates
- Verify DTC P103B, P103C is not set.
- If a related DTC is set
- Ignition/Vehicle - Off
- Disconnect the electrical connector: B52B Heated Oxygen Sensor 2
- Disconnect the electrical connector: X3 @ K20 Engine Control Module
- Test for less than 2 ohms between the test points: Ignition circuit terminal 2 @ B52B Heated Oxygen Sensor 2 (harness side) & Terminal 16 X3 @ Control module harness
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Test or replace the component: K20 Engine Control Module
- Go to next step: If a related DTC is not set
- Verify that a test lamp does not illuminate between the ignition voltage circuit terminal 2 and the control circuit terminal 1.
- If the test lamp illuminates
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for infinite resistance between the control circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance, replace the K20 Engine Control Module.
- Go to next step: If the test lamp does not illuminate
- Remove the test lamp.
- Verify the scan tool HO2S 1 or 2 Heater Control Circuit High Voltage Test Status parameter is OK when commanding the HO2S Heater Sensor 1 or 2 ON with a scan tool.
- If OK is not displayed
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
- Test for less than 1 V between the control circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K20 Engine Control Module.
- Go to next step: If OK is displayed
- Less than 10 Ω of additional resistance on the ignition voltage circuit, or control circuit may set a DTC. If there is a resistance on a circuit, the driver will remain ON and the scan tool HO2S High Voltage Test Status parameter will display OK.
- Performing this test may set additional DTCs.
- Install a 10 A fused jumper wire between the control circuit terminal 1 and the ignition voltage circuit terminal 2.
- Verify the scan tool HO2S 1 or 2 Heater Control Circuit High Voltage Test Status parameter is Malfunction when commanding the HO2S Heater Sensor 1 or 2 ON with a scan tool.
- If Malfunction is not displayed
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for less than 2 Ω in the control circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- Go to next step: If Malfunction is displayed
- Test or replace the B52 Heated Oxygen Sensor.
NOTE:
NOTE:
This test may only be performed once per key cycle. If test is repeated, ignition OFF, allow the engine control module to shut down completely, then ignition ON.