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Engine Control Module: Testing and Inspection

ECU Testing:






1. Lift up floormat in front of passenger seat.
2. Connect Mazda SST, or aftermarket equivalent, between PCME and wiring harness using adapter.

CAUTION: Applying voltage to SST terminals A or B will damage the unit.

3. Measure voltage at each terminal as shown on terminal voltage chart.
4. If any terminal voltage is incorrect, check the input or output device and related wiring. For troubleshooting help, see Terminal Check Points below.
5. If no problems are detected, replace PCME.

PCME TERMINAL VOLTAGE CHART

PART 1

PCME Pin Voltage Chart (Part 1):






PART 2

PCME Pin Voltage Chart (Part 2):






PART 3

PCME Pin Voltage Chart (Part 3):






TERMINAL CHECK POINTS

PART 1

Terminals 1A - 1L:






PART 2

Terminals 1M - 1U:






PART 3

Terminals 1V - 2O:






PART 4

Terminals 2P - 2Z:




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