DTC P1127 [MZI-3.7]
DTC P1127 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES
DIAGNOSTIC PROCEDURE
DTC P1127 (MZI-3.7) DIAGNOSTIC PROCEDURE
DTC P1127
Exhaust temperature out of range, HO2S tests not completed
DETECTION
CONDITION
z
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
z
Engine not operating long enough prior to carrying out the KOER self-test
z
Exhaust system too cool
STEP
INSPECTION
ACTION
1
VERIFY FREEZE FRAME DATA HAS
BEEN RECORDED
z
Has FREEZE FRAME DATA been
recorded?
Yes Go to the next step.
No
Record FREEZE FRAME DATA on the repair
order, then go to next step.
2
VERIFY RELATED REPAIR
INFORMATION AVAILABILITY
z
Verify related Service Bulletins
availability.
z
Is any related Service Bulletins
available?
Yes
Perform repair or diagnosis according to
available Service Bulletins.
z
If vehicle is not repaired, go to next step.
No
Go to the next step.
3
EXHAUST TEMPERATURE OUT OF
RANGE
z
Turn the ignition switch to the ON
position (Engine running)
z
Verify that the engine is at normal
operating temperature.
z
Access the PCM and monitor the
HO2S heater PID.
z
Is the PID state ON?
NOTE:
z
Address all other DTCs before
proceeding.
Yes
Perform the KOER self-test, then go to the next
step. (See
KOEO/KOER SELF TEST [MZI-
3.7]
.)
No
Run the engine until the PID indicates ON.
Perform the KOER self-test, then go to the next
step.
(See
KOEO/KOER SELF TEST [MZI-3.7]
.)
VERIFY TROUBLESHOOTING OF
DTC P1127 HAS BEEN COMPLETED
2008 Mazda CX-9 Grand Touring
2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:08:40 AM
Page 316
© 2005 Mitchell Repair Information Company, LLC.
