Diagnostic Test

WARNING: This page is about a different car, the 2006 Chrysler PT Cruiser. However, it is still accessible from the selected car via links, so may be relevant.

1) GOOD TRIP INDICATED
Turn the ignition on.

With the scan tool, read DTC's.

Does the Good Trip Indicator display NO?

Yes
1. Go To 3).
No
1. Go To 2).
2) O2 SENSOR HEATER OPERATION
Turn the ignition off.

NOTE: Wait a minimum of 8 minutes to allow the O2 Sensor to cool down before continuing the test. Allow the O2 Sensor voltage to stabilize between 0.4 to 0.6 volts.

Turn the ignition on.

With the scan tool, actuate the O2 Heater.

With the scan tool, monitor O2 Sensor voltage for at least 2 minutes.

Does the voltage stay between 0.4 and 0.6 volts?

Yes
1. Go To 3).
No
1. Refer to the INTERMITTENT CONDITION diagnostic procedure.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
3) O2 HEATER ELEMENT
NOTE: Allow the O2 sensor to cool down to room temperature.

Turn the ignition off.

Disconnect the O2 Sensor harness connector.

Measure the resistance across the O2 Sensor Heater element component side.

NOTE: Heater Resistance Specification for 1/1 and 1/2 O2 Sensor is from 3 to 20 ohms.

Is the O2 Sensor Heater element within specification?

Yes
1. Go To 4).
No
1. Replace the O2 Sensor.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
4) O2 SENSOR HEATER GROUND CIRCUIT SHORT TO GROUND

Fig 1: MEASURING RESISTANCE BETWEEN GROUND AND THE O2 SENSOR HEATER GROUND CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance between ground and the O2 Sensor Heater ground circuit in the O2 Sensor harness connector.

Is the resistance below 5.0 ohms?

Yes
1. Go To 5).
No
1. Repair the open O2 Sensor Heater ground circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
5) ASD RELAY OUTPUT CIRCUIT

Fig 2: MEASURING VOLTAGE OF THE ASD RELAY OUTPUT CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition on.

With the scan tool, actuate the O2 Heater Test.

Measure the voltage of the ASD Relay Output circuit in the O2 Sensor harness connector.

Is the voltage above 11.0 volts?

Yes
1. Go To 6).
No
1. Repair the ASD Relay Output circuit for an open.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
6) PCM
NOTE: Before Continuing: Disconnect the PCM harness connector and check the related wiring terminals for corrosion, damage or terminal push out. Repair as necessary.

Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

If there are no possible causes remaining, view repair.

Repair
1. Replace and program the Powertrain Control Module in accordance with the Service Information. (Refer to STANDARD PROCEDURE - PCM/ECM/SKREEM PROGRAMMING) .
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .