DTC P0128 [MZI-3.7]
DTC P0128 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES
DIAGNOSTIC PROCEDURE
DTC P0128 (MZI-3.7) DIAGNOSTIC PROCEDURE
z
Are there any malfunction?
No
Go to the next step.
8
VERIFY TROUBLESHOOTING OF
DTC P0123 HAS BEEN COMPLETED
z
Make sure to reconnect all
disconnected connectors.
z
Clear the DTC from the PCM memory
using the M-MDS.
z
Start the engine.
z
Perform the "KOEO/KOER self-test".
(See
KOEO/KOER SELF TEST
[MZI-3.7]
.)
z
Is same DTC present?
Yes
Replace the PCM, then go to the next step. (See
PCM REMOVAL/INSTALLATION [MZI-
3.7]
.)
No
Go to the next step.
9
VERIFY AFTER REPAIR PROCEDURE
z
Perform the "AFTER REPAIR
PROCEDURE". (See
AFTER
REPAIR PROCEDURE [MZI-3.7]
.)
z
Are any DTCs present?
Yes
Go to the applicable DTC inspection. (See
DTC
TABLE [MZI-3.7]
.)
No
Troubleshooting completed.
DTC P0128
Coolant thermostat (coolant temp below thermostat regulating temperature)
DETECTION
CONDITION
z
P0128 Indicates that the thermostat monitor has not achieved the required
engine operating temperature within a specified amount of time after starting
the engine.
POSSIBLE CAUSE
z
Insufficient warm up time
z
Low engine coolant level
z
Leaking or stuck open thermostat
z
Inoperative cylinder head temperature (CHT) sensor
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 the next step.
VERIFY RELATED REPAIR INFORMATION
Perform repair or diagnosis according to
2008 Mazda CX-9 Grand Touring
2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:08:35 AM
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© 2005 Mitchell Repair Information Company, LLC.
