DTC P1127:00 [MZI-3.7]


id0102d2316700

DTC P1127:00

Exhaust temperature out of range, HO2S tests not completed

DETECTION CONDITION
•  The HO2S monitor uses an exhaust temperature model to determine when the HO2S heaters are cycled ON. The test fails when the inferred exhaust temperature is below a minimum calibrated value.
POSSIBLE CAUSE
•  Exhaust system too cool
•  Engine not operating long enough prior to carrying out the KOER self-test
•  PCM malfunction

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 FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY RELATED 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
EXHAUST TEMPERATURE OUT OF RANGE
Note
•  Address all other DTCs before proceeding.
•  Turn the ignition switch to the ON position (Engine running)
•  Verify that the engine is at normal operating temperature.
•  Access the PCM and monitor the HO2S heater PID.
•  Is the PID state ON?
Yes
Perform the KOER self-test.
Go to the next step.
No
Run the engine until the PID indicates ON.
Perform the KOER self-test.
Go to the next step.
4
VERIFY TROUBLESHOOTING OF DTC P1127:00 HAS BEEN COMPLETED
•  Verify that all disconnected connectors reconnected.
•  Clear DTC from memory using M-MDS.
•  Start engine.
•  Perform the KOEO or KOER self-test.
•  Is same DTC present?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM.
Go to the next step.
No
Go to the next step.
5
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.