Mazda CX-7 2007 Workshop Manual page 136

STEP
5 VERIFY CURRENT INPUT SIGNAL STATUS
• Warm up the engine.
• Access the O2S12 or the P0140 PID using the
M-MDS.
• Verify the PID while racing the engine at least
10 times in NEUTRAL.
• Is the PID reading normal?
— More than 0.55 V at least once during
engine racing
6 INSPECT INSTALLATION OF REAR HO2S
• Check if the rear HO2S is loosely installed.
• Is the sensor installed securely?
7 INSPECT GAS LEAKAGE FROM EXHAUST
SYSTEM
• Visually check if any gas leakage is found
between the exhaust pipe and the rear HO2S.
• Is there gas leakage?
8 INSPECT SEALING OF ENGINE COOLANT
PASSAGE
• Perform the ENGINE COOLANT LEAKAGE
INSPECTION.
(See01-12-6 ENGINE COOLANT LEAKAGE
INSPECTION[L3 WITH TC].)
• Is the cooling system hold pressure normal?
9 INSPECT ENGINE COMPRESSION
• Inspect the engine compression.
(See01-10-9 COMPRESSION
INSPECTION[L3 WITH TC].)
• Is it normal?
10 VERIFY TROUBLESHOOTING OF DTC P0140
COMPLETED
• Make sure to reconnect all disconnected
connectors.
• Turn the ignition switch to the ON position.
(Engine off)
• Clear the DTC from the memory using the M-
MDS.
• Perform the HO2S heater, HO2S, and TWC
Repair Verification Drive Mode.
(See01-02-10 OBD-II DRIVE MODE[L3 WITH
TC].)
• Is the PENDING CODE for this DTC present?
11 VERIFY AFTER REPAIR PROCEDURE
• Perform the "AFTER REPAIR PROCEDURE".
(See01-02-10 AFTER REPAIR
PROCEDURE[L3 WITH TC].)
• Are any DTCs present?
End Of Sie
01-02–94
ON-BOARD DIAGNOSTIC [L3 WITH TC]
INSPECTION
Yes Go to Step 8.
No Go to the next step.
Yes Go to the next step.
No Install the sensor securely, then go to Step 10.
Yes Repair or replace any malfunctioning exhaust part, then go
to Step 10.
• Inspect the following wiring harness for an open or short
No
to the ground circuit, repair or replace the wiring
harness if necessary.
— Rear HO2S terminal A (wiring harness-side) to PCM
terminal 2Q (wiring harness-side)
• Repair or replace the wiring harness if necessary.
• If all items above are normal, replace the malfunctioning
sensor.
Then go to Step 10.
Yes Repair or the replace the malfunctioning part according to
the inspection result.
Then go to Step 10.
No Go to the next step.
Yes Go to the next step.
No Perform engine overhaul for repairs, then go to the next
step.
Yes Replace the PCM, then go to the next step.
(See01-40-6 PCM REMOVAL/INSTALLATION[L3 WITH
TC].)
No Go to the next step.
Yes Go to the applicable DTC troubleshooting.
(See01-02-13 DTC TABLE[L3 WITH TC].)
No Troubleshooting completed.
ACTION