DTC P0151[AJ (3.0L Duratec)]

id0102a4817700

DTC P0151

Front HO2S (LH) sensor circuit out of range low voltage
DETECTION CONDITION
•  The PCM monitors the front HO2S (LH) voltage at the PCM terminal 87. If during testing the PCM detects that the front HO2S (LH) alternates between 0 and -1 V, the PCM determines the front HO2S (LH) circuit is out of range low voltage.
POSSIBLE CAUSE
•  Contaminated front HO2S (LH) (water, fuel, etc.)
•  Crossed front HO2S (LH) signal/signal return wiring

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
•  Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA
•  Is DTC P0151 on the FREEZE FRAME DATA?
Yes
Go to the next step.
No
Go to the FREEZE FRAME DATA DTC inspection.
(See DTC TABLE[AJ (3.0L Duratec)].)
4
CHECK FOR SOURCE OF POTENTIAL FRONT HO2S (RH) CONTAMINATION
•  Investigate the following items as potential sources of front HO2S (LH) contamination:
―  Use of unapproved silicon sealers.
―  Fuel contaminated by silicon additives.
―  Excessive oil burning. (rings, valve seals, oil overfill).
―  Glycol leaking internally in the engine.
―  Leaded-contaminated fuel.
―  Short drive cycles in cold weather.
―  Use of unapproved cleaning agents.
•  Were any of the above conditions or concerns found during inspection?
Yes
Repair the source of contamination.
Then go to Step 6.
No
Go to the next step.
5
VERIFY HARNESS PINS ARE IN PROPER LOCATION
•  Measure the resistance between the following at the harness side connector.
―  Between the PCM terminal 87 and front HO2S (LH) terminal B.
―  Between the PCM terminal 91 and front HO2S (RH) terminal D.
•  Is the resistance below 5 ohms?
Yes
Replace the front HO2S (LH), then go to the next step.
No
Repair harness pin locations, then go to the next step.
6
VERIFY TROUBLESHOOTING OF DTC P0151 COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Drive the vehicle at 64 km/h {40 MPH} for at least 5 minutes.
•  Is the PENDING CODE same DTC present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION[AJ (3.0L Duratec)].)
No
Go to the next step.
7
VERIFY AFTER REPAIR PROCEDURE
•  Perform “AFTER REPAIR PROCEDURE”.
•  Is there any DTC present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE[AJ (3.0L Duratec)].)
No
Troubleshooting completed.