Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2012 Mazda Mazdaspeed3 L4-2.3L TurboFACTORY OEM SERVICE PROCEDURE
Pinout Values and Diagnostic Parameters
PCM INSPECTION [MZR 2.3 DISI Turbo]
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 terminal voltage table (Reference)
*1
Without advanced keyless entry and push button start system
*2
With advanced keyless entry and push button start system
Inspection Using An Oscilloscope (Reference)
APP sensor (No.2) signal
Accelerator pedal released
Accelerator pedal depressed
PCM terminals
- 1AC (+)-body ground (-)
Oscilloscope setting
- 5 V/DIV (Y), 5 ms/DIV (X), DC range
Vehicle condition
- Idle after warm up
Fan control module signal
PCM terminals
- 1AE (+)-body ground (-)
Oscilloscope setting
- 5 V/DIV (Y), 5 ms/DIV (X), DC range
Vehicle condition
- Idle after warm up
Generator field coil control signal
PCM terminals
- 1AW (+)-body ground (-)
Oscilloscope setting
- 0.5 V/DIV (Y), 2 ms/DIV (X), DC range
Vehicle condition
- Idle after warm up
Generator output voltage signal
PCM terminals
- 1AX (+)-body ground (-)
Oscilloscope setting
- 2 V/DIV (Y),1 ms/DIV (X), DC range
Vehicle condition
- Idle after warm up
A/F sensor heater control signal
PCM terminals
- 2C (+)-body ground (-)
Oscilloscope setting
- 5 V/DIV (Y), 200 ms/DIV (X), DC range
Vehicle condition
- Idle after warm up
CMP sensor signal
PCM terminals
- 2S (+)-body ground (-)
Oscilloscope setting
- 2 V/DIV (Y), 100 ms/DIV (X), DC range
Vehicle condition
- Idle after warm up
CKP sensor signal
PCM terminals
- 2W (+)-body ground (-)
Oscilloscope setting
- 2 V/DIV (Y), 5 ms/DIV (X), DC range
Vehicle condition
- Idle after warm up
Wastegate control solenoid valve signal
PCM terminals
- 2AA (+)-body ground (-)
Oscilloscope setting
- 20 V/DIV (Y), 20 ms/DIV (X), DC range
Vehicle condition
- Switch the ignition to ON
Purge control signal
PCM terminals
- 2AB (+)-body ground (-)
Oscilloscope setting
- 10 V/DIV (Y), 20 ms/DIV (X), DC range
Vehicle condition
- Racing
OCV signal
PCM terminals
- 2AF (+)-body ground (-)
Oscilloscope setting
- 5 V/DIV (Y), 1 ms/DIV (X), DC range
Vehicle condition
- Racing
IGT1, IGT2, IGT3, IGT4 control signals
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
Fuel injection control (-)
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
Fuel injection control (+)
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
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 Testing and Inspection
- Main relay
1. Connect the M-MDS to the DLC-2.
2. Switch the ignition to ON.
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, FP, IMRC, INJ_1, INJ_2, INJ_3, INJ_4, SEGRP, TEST, VT DUTY1 wt, WGC
PID/DATA monitor table (reference)
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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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