Diagnostic Test

1) PRE-DIAGNOSTIC CHECK OUT

Fig 1: Connecting Scan Tool & Turning Ignition On
Courtesy of DAIMLERCHRYSLER CORP.

NOTE: Always perform diagnostics with a fully charged battery.

NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal connections can set DTCs.

NOTE: Check for applicable TSBs related to the problem.

Turn the ignition on.

With the DRB III®, read PCM DTCs.

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors. Repair as necessary.

Perform this procedure prior to symptom diagnosis.

Continue
1. Go To 2).
2) CHECK FOR CURRENT DTC

Fig 2: Connecting Scan Tool & Turning Ignition On
Courtesy of DAIMLERCHRYSLER CORP.

NOTE: It is important to perform the diagnostics on the O2 Sensor that set the DTC.

NOTE: Check for contaminates that may have damaged the O2 Sensor: contaminated fuel, unapproved silicone, oil and coolant.

NOTE: If the PCM detects and stores a DTC, the PCM also stores the engine/vehicle operating conditions under which the DTC was set. Some of these conditions are displayed on the DRB III® at the same time the DTC is displayed.

NOTE: Before erasing stored DTCs, record these conditions. Attempting to duplicate these conditions may assist when checking for an active DTC.

Turn the ignition on.

With the DRB III®, erase PCM DTCs.

NOTE: It maybe necessary to road test the vehicle for this DTC to set.

With the DRB III®, read PCM DTCs.

Did this DTC set again?

Yes
1. Go To 3).
No
1. Go To 6).
3) EXHAUST LEAK
Start the engine.

Inspect the exhaust system for leaks between the engine and the O2 Sensors. (Refer to EXHAUST SYSTEM - INSPECTION) .

Are there any exhaust leaks?

Yes
1. Repair or replace the leaking exhaust parts as necessary. (Refer to EXHAUST SYSTEM/CATALYTIC CONVERTER - REMOVAL) .
2. Perform POWERTRAIN VERIFICATION TEST - VER 2 .
No
1. Go To 4).
4) O2 SIGNAL CIRCUIT

Fig 3: Checking Sensor Signal Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off

Disconnect the O2 Sensor harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Turn the ignition on.

Measure the voltage of the O2 Signal circuit at the O2 Sensor harness connector.

Is the voltage approximately 0.47 volt?

Yes
1. Go To 5).
No
1. Check the O2 Signal circuit for damage, short to ground, open, or short to voltage. If OK, replace and program the Powertrain Control Module. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/POWERTRAIN CONTROL MODULE - REMOVAL) .
2. Perform POWERTRAIN VERIFICATION TEST - VER 2 .
5) SENSOR GROUND CIRCUIT

Fig 4: Checking Sensor Ground Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Disconnect the PCM harness connectors.

NOTE: Check connectors - Clean/repair as necessary.

Measure the resistance of the Sensor Ground circuit from the O2 Sensor harness connector to the PCM harness connector.

Is the resistance below 5.0 ohms?

Yes
1. Replace the Oxygen Sensor. (Refer to FUEL SYSTEM/FUEL INJECTION/O2 SENSOR - REMOVAL) .
2. Perform POWERTRAIN VERIFICATION TEST - VER 2 .
No
1. Check the Sensor Ground circuit for damage, short to ground, open, or short to voltage. If OK, replace and program the Powertrain Control Module. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/POWERTRAIN CONTROL MODULE - REMOVAL) .
2. Perform POWERTRAIN VERIFICATION TEST - VER 2 .
6) INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.

NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors specific to this DTC. Wiggle the wires while checking for shorts and open circuits.

NOTE: Check for any Technical Service Bulletins that may apply.

Were there any problems found?

Yes
1. Repair as necessary.
2. Perform POWERTRAIN VERIFICATION TEST - VER 2 .
No
1. The condition that caused this DTC to set is currently not present. Inspect the related wiring harness for a possible intermittent condition.