DTC P0645 [MZI-3.7]
DTC P0645 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES
7
VERIFY TROUBLESHOOTING OF
DTC P0643 HAS BEEN COMPLETED
z
Verify that all disconnected
connectors reconnected.
z
Clear the DTC from the PCM
memory using the M-MDS.
z
Perform the "KOEO or KOER self-
test" using the M-MDS. (See
KOEO/KOER SELF TEST [MZI-
3.7]
.)
z
Is the PENDING CODE for the
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.
8
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 P0645
A/C relay control circuit
DETECTION
CONDITION
z
Monitors the A/C relay control circuit output from the PCM. The test fails when the
PCM grounds the A/C relay control circuit, excessive current draw is detected on the
A/C relay control circuit; or, with the A/C relay control circuit not grounded by the
PCM, voltage is not detected on the A/C relay control circuit (the PCM expects to
detect vehicle power voltage coming through the A/C relay coil to the A/C circuit).
POSSIBLE
CAUSE
z
A/C relay malfunction
z
Connector or terminal malfunction
z
Open circuit in wiring between main relay terminal No.1 D and A/C relay terminal A
z
Open circuit in wiring between A/C relay terminal E and PCM terminal IN
z
Short to ground in wiring between A/C relay terminal E and PCM terminal 1N
z
Short to power supply between A/C relay terminal E and PCM terminal 1N
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 296
© 2005 Mitchell Repair Information Company, LLC.
