Pcm Power Relay

NOTE:

The IGN START/RUN and ground circuits, or the B+ and VPWR circuits may be reversed in the harness connector. See appropriate SYSTEM WIRING DIAGRAMS article for schematic and connector information.

POSSIBLE CAUSES

Harness circuits: B+, IGN START/RUN, INJPWRM, ISP-R, PCMRC, VPWR and GND
PCM power relay
PCM

Fig 1: Identifying Injector (INJ) Connector Terminals

Courtesy of MAZDA MOTORS CORP.

Injector (INJ) Connector

Fig 2: Identifying Powertrain Control Module Power (PCM Power) Relay Connector Terminals

Courtesy of MAZDA MOTORS CORP.

Powertrain Control Module Power (PCM Power) Relay Connector

DTC DETECTION CONDITION POSSIBLE COUSES CHART

STEP	INSPECTION		ACTION
1	CHECK FOR DTCs Is DTC P0562, P0563, P0685, P0689, or P0690 present?	Yes	For DTC P0562 or P0563, GO to the next step. For DTC P0685 or P0690, GO to step 8. For DTC P0689, GO to step 11.
1		No	GO to the next step.
2	CHECK THE B+ AND IGN START/RUN VOLTAGE TO PCM POWER RELAY Key OFF. PCM power relay connector disconnected. Key ON, engine OFF (KOEO). Measure the voltage between PCM power relay connector B+, harness side and ground. Measure the voltage between PCM power relay connector IGN START/RUN, harness side and ground. Are the voltages greater than 10 V?	Yes	GO to the next step.
2		No	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
3	CHECK THE PCMRC CIRCUIT FOR AN OPEN IN THE HARNESS Key OFF. PCM connector disconnected. Measure the resistance between PCM power relay connector PCMRC, harness side and PCM connector PCMRC, harness side Is the resistance less than 5 ohms?	Yes	GO to the next step.
3		No	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
4	CHECK THE PCMRC CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS Key ON, engine OFF (KOEO). Measure the voltage between PCM connector PCMRC, harness side and ground. Is any voltage present?	Yes	REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test.
4		No	GO to the next step.
5	CHECK THE ISP-R VOLTAGE AT THE PCM HARNESS CONNECTOR Key OFF. PCM power relay connector connected. Key ON, engine OFF (KOEO). Measure the voltage between PCM connector ISP-R, harness side and ground. Is the voltage greater than 10 V?	Yes	GO to step 7.
5		No	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
6	CHECK THE PCM POWER RELAY GROUND CIRCUIT FOR AN OPEN Measure the voltage between PCM power relay connector B+, harness side and PCM power relay connector GND, harness side. Is the voltage greater than 10 V?	Yes	GO to the next step.
6		No	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
7	CHECK FOR AN OPEN VPWR CIRCUIT BETWEEN THE PCM AND POWER RELAY Key OFF. PCM connector disconnected. Measure the resistance between PCM power relay connector VPWR, harness side and PCM connector VPWR, harness side. Is the resistance less than 5 ohms?	Yes	INSTALL a new PCM power relay. CLEAR the DTCs. REPEAT the self-test.
7		No	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
8	DTCs P0685 OR P0690: CHECK THE PCMRC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS Key OFF. PCM power relay connector disconnected. PCM connector disconnected. Measure the resistance between PCM connector PCMRC, harness side and ground. Is the resistance greater than 10K ohms?	Yes	GO to the next step.
8		No	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
9	CHECK THE ISP-R CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS Key OFF. Measure the voltage between PCM connector ISP-R, harness side and ground. Is any voltage present?	Yes	REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test.
9		No	GO to the next step.
10	CHECK THE INJPWRM CIRCUIT FOR AN OPEN IN THE HARNESS INJ connector disconnected. Measure the resistance between PCM connector INJPWRM, harness side and INJ connector VPWR, harness side. Is the resistance less than 5 ohms?	Yes	GO to step 12.
10		No	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
11	DTC P0689: CHECK THE ISP-R VOLTAGE AT THE PCM HARNESS CONNECTOR Key OFF. PCM connector disconnected. Key ON, engine OFF (KOEO). Measure the voltage between PCM connector ISP-R, harness side and ground. Is the voltage greater than 10 V?	Yes	GO to the next step.
11		No	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
12	VERIFY TROUBLESHOOTING OF DTCs COMPLETED Disconnect all the PCM connectors. Check for: corrosion damaged pins pushed-out pins Connect all connectors and make sure they seat correctly. Clear DTCs from PCM memory using IDS or equivalent generic OBD II tester. Carry out the PCM Quick Test. See PCM QUICK TEST . Is same DTC present?	Yes	INSTALL a new PCM. See POWERTRAIN CONTROL MODULE (PCM) REMOVAL/INSTALLATION - 2.5L or POWERTRAIN CONTROL MODULE (PCM) REMOVAL/INSTALLATION - 3.0L . REPEAT the PCM Quick Test. See PCM QUICK TEST .
12		No	If any other DTC is present, go to applicable DTC inspection. If no DTC is present, troubleshooting complete.