7
z
Visually inspect the HO2S circuit for
exposed wiring, contamination, corrosion and
correct assembly. Repair if necessary.
z
Measure the voltage between HO2S terminal
B and D on the component side.
z
Increase the engine speed to 2,000 rpm for 3
min.
z
Turn the ignition switch to the ON position
(Engine running)
z
Monitor the signal voltage.
z
Is the voltage more than 0.5 V at any time
during the engine running?
Yes Go to the next step.
No
Replace the HO2S.
Then go to Step 9.
8
PERFORM THOROUGH WIGGLE TEST ON
HO2S WIRING HARNESS
z
Turn the ignition switch off.
z
Connect the HO2S connector.
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
signal PID.
z
Wiggle, shake, and bend small sections of the
wiring harness while working from the
sensor to the PCM.
z
While monitoring the HO2S PID, does the
HO2S stop switching?
Yes
Isolate the concern and repair if
necessary.
Then go to the next step.
No
Go to the next step.
9
VERIFY TROUBLESHOOTING OF DTC
P0172, P0175 HAS BEEN COMPLETED
z
Verify that all disconnected connectors are
reconnected.
z
Turn the ignition switch to the ON position
(Engine off).
z
Clear the DTC from the PCM memory using
the M-MDS.
z
Start the engine and run it at idle.
z
Retrieve DTCs using the M-MDS.
z
Is the PENDING CODE for this 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.
VERIFY AFTER REPAIR PROCEDURE
2008 Mazda CX-9 Grand Touring
2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:08:36 AM
Page 115
© 2005 Mitchell Repair Information Company, LLC.
