2012 Mazda CX-7 FWD L4-2.3L TurboFACTORY OEM SERVICE PROCEDURE

Component Tests and General Diagnostics





PCM INSPECTION [L3 WITH TC]

Without Using the M-MDS

NOTE:
- The PCM terminal voltage can vary with the conditions when measuring and changes due to aged deterioration on the vehicle, causing false diagnosis. Therefore determine comprehensively where the malfunction occurs among the input systems, output systems, and the PCM.

PCM inspection preparation

1. Disconnect the negative battery cable.

2. Remove the battery and battery tray. Removal and Replacement

3. Remove the windshield wiper arm and blade. (See Windshield Wiper Arm And Blade Removal/Installation.)

4. Remove the cowl grille. (See Cowl Grille Removal/Installation.)

5. Remove the windshield wiper motor. (See Windshield Washer Motor Removal/Installation.)

6. Remove the cowl panel. (See Cowl Panel Removal/Installation.)

7. Remove the PCM bracket with the PCM connector still connected. (See Service and Repair.)

8. Install the battery and battery tray. Removal and Replacement

9. Connect the negative battery cable.

PCM terminal voltage table (Reference)

Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Inspection Using An Oscilloscope (Reference)

Fan control module signal

Factory service manual diagram




PCM terminals
- 1R (+)-body ground (-)
- 1AE (+)-body ground (-)

Oscilloscope setting
- 5 V/DIV (Y), 20 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

Generator field coil control signal

Factory service manual diagram




PCM terminals
- 1AW (+)-body ground (-)

Oscilloscope setting
- 0.5 V/DIV (Y), 2 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (engine speed approx. 650 rpm, no load)

Generator output voltage signal

Factory service manual diagram




PCM terminals
- 1AX (+)-body ground (-)

Oscilloscope setting
- 2 V/DIV (Y),1 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

A/F sensor heater control signal

Factory service manual diagram




PCM terminals
- 2C (+)-body ground (-)

Oscilloscope setting
- 2 V/DIV (Y), 20 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

CMP sensor signal

Factory service manual diagram




PCM terminals
- 2S (+)-body ground (-)

Oscilloscope setting
- 2 V/DIV (Y), 100 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

CKP sensor signal

Factory service manual diagram




PCM terminals
- 2W (+)-body ground (-)

Oscilloscope setting
- 2 V/DIV (Y), 5 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

Wastegate control solenoid valve signal

Factory service manual diagram




PCM terminals
- 2AA (+)-body ground (-)

Oscilloscope setting
- 20 V/DIV (Y), 20 ms/DIV (X), DC range

Vehicle condition
- Ignition switch to the ON position

Purge control signal

Factory service manual diagram




PCM terminals
- 2AB (+)-body ground (-)

Oscilloscope setting
- 10 V/DIV (Y), 20 ms/DIV (X), DC range

Vehicle condition
- Engine speed is 2,000 rpm

OCV signal

Factory service manual diagram




PCM terminals
- 2AF (+)-body ground (-)

Oscilloscope setting
- 2.5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

IGT1, IGT2, IGT3, IGT4 control signals

Factory service manual diagram




PCM terminals
- IGT1 (No.1): 2BA (+)-body ground (-)
- IGT2 (No.2): 2AW (+)-body ground (-)
- IGT3 (No.3): 2AX (+)-body ground (-)
- IGT4 (No.4): 2AT (+)-body ground (-)

Oscilloscope setting
- 2 V/DIV (Y), 20 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

Fuel injection control (-)

Factory service manual diagram




PCM terminals
- Fuel injection No.1: 2BB (+)-body ground (-)
- Fuel injection No.2: 2BC (+)-body ground (-)
- Fuel injection No.3: 2BD (+)-body ground (-)
- Fuel injection No.4: 2AZ (+)-body ground (-)

Oscilloscope setting
- 10 V/DIV (Y), 20 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

Fuel injection control (+)

Factory service manual diagram




PCM terminals
- Fuel injection No.1, No.4: 2BG (+)-body ground (-)
- Fuel injection No.2, No.3: 2BH (+)-body ground (-)

Oscilloscope setting
- 20 V/DIV (Y), 400 microsecond/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

Using the M-MDS

NOTE:
- PIDs for the following parts are not available on this model. Perform the specific inspections for the following parts:

- CMP sensor (See Testing and Inspection.)
- Main relay

1. Connect the M-MDS to the DLC-2.

Factory service manual diagram





2. Turn the ignition switch to the ON position.

3. Measure the PID value.

- If PID value is not within the specification, follow the instructions in the "Inspection item" column.

NOTE:
- The PID/DATA MONITOR function monitors the calculated value of the input/output signals in the PCM. Therefore, an output device malfunction is not directly indicated as a malfunction of the monitored value for the output device. If a monitored value of an output device is out of specification, inspect the monitored value of the input device related to the output control.
- For input/output signals except those of the monitoring items, use a voltmeter to measure the PCM terminal voltage.
- The simulation items that are used in the ENGINE CONTROL SYSTEM OPERATION INSPECTION are as follows.

- ACCS, ALTF, ARPMDES, EVAPCP, EVAPCV, FAN_DUTY, FAN_DUTY2, FP, IMRC, INJ_1, INJ_2, INJ_3, INJ_4, SEGRP, TEST, VT DUTY1 Wt, WGC

PID/DATA monitor table (reference)

Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory service manual diagram




Factory Service Tools

Use the Manual With the Right Hardware

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

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