Mazda CX-9 Grand Touring 2009 Manual page 1335

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
Ignition wiring
Electrical connections
Fuses
Smooth operation of throttle valve
PCM GND circuit (1D, U, 1BP,
1BK)
Are all items normal?
Connect the M-MDS to the DLC-2.
Turn the ignition switch to the ON position
3 (Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?
4 Is the engine overheating?
Connect the M-MDS to the DLC-2.
Access MAF PID.
5
Drive vehicle with monitoring PID. Is
MAF PID within specification?
NOTE:
The following test is for engine
running at rough idle with A/C on.
If other symptoms exist, go to the
next step.
6
Connect pressure gauge to A/C low and
high pressure side lines.Start engine and
idle it.Turn the A/C switch on.Measure low
side and high side pressures.Are pressures
within specifications?(See
REFRIGERANT PRESSURE
CHECK .)
NOTE:
The following test is for engine
running rough with P/S on. If other
7
symptoms exist, go to the next
step.
Connect the M-MDS to the DLC-2.Start
2008 Mazda CX-9 Grand Touring
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Service if necessary.
Repeat Step 2.
DTC is displayed:
Go to the appropriate DTC inspection.
(See DTC TABLE [MZI-3.7] .)
No DTC is displayed:
Go to the next step.
Go to symptom troubleshooting "No.17
Cooling system concerns - Overheating".
(See NO.17 COOLING SYSTEM
CONCERNS-OVERHEATING [MZI-
3.7].)
Go to the next step.
Go to the next step.
Inspect for open or short circuit of MAF
sensor and related wiring harness.
Go to the next step.
If the A/C is always on, go to symptom
troubleshooting "No.24 A/C is always on
or A/C compressor runs continuously".
(See NO.24 A/C IS ALWAYS ON OR
A/C COMPRESSOR RUNS
CONTINUOUSLY [MZI-3.7].)
For other symptoms, inspect the
following:
Refrigerant charging amount
Condenser fan operation
Go to the next step.
Inspect power steering pressure switch
operation and wiring harness between P/S
pressure switch and PCM terminal 21.