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HOMESERVICE MANUALSMAZDA2008TRIBUTE S SPORT, 4WDREPAIR AND DIAGNOSISENGINE PERFORMANCEFUEL DELIVERYSYMPTOM TROUBLESHOOTING [ENGINE/FUEL - EXCEPT HYBRID]POWERTRAIN CONTROL MODULE (PCM) POWER RELAY
2008 Mazda Tribute s Sport, 4WD

Powertrain Control Module (Pcm) Power Relay

2008 Mazda Tribute s Sport, 4WDSECTION Powertrain Control Module (Pcm) Power Relay
NOTE:
  • The IGN START/RUN and ground circuits, or the B+ and VPWR circuits may be reversed in the harness connector. Refer to the for schematic and connector information.

POSSIBLE CAUSE

  • Harness circuits: B+, IGN START/RUN, INJPWRM, ISP-R, PCMRC, VPWR and GND
  • PCM power relay
  • PCM
Fig 1: Identifying Injector Connector (INJ)
G05463754Courtesy of MAZDA MOTORS CORP.

Injector (INJ) Connector 

Fig 2: Identifying Powertrain Control Module Power Relay Connector (PCM Power)
G05463680Courtesy of MAZDA MOTORS CORP.

Powertrain Control Module Power (PCM Power) Relay Connector 

INSPECTION CHART - POWERTRAIN CONTROL MODULE POWER (PCM POWER) RELAY CONNECTOR

STEP INSPECTION ACTION
1 CHECK FOR DTCs
  • Is DTC P0685, P0689, or P0690 present? 
 Yes For DTCs P0685 or P0690, GO to step 8.
For DTC P0689, GO to step 11.
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 step 6.
No REPAIR the open circuit. CLEAR the DTCs.
REPEAT the self-test.
3 CHECK THE PCMRC CIRCUIT FOR AN OPEN IN THE HARNESS
NOTE:
  • If KAPWR is interrupted to the PCM (when the battery is disconnected), DTCs P0603/P1605 can be generated on the first power-up.
  • 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.
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.
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.
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.
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.
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.
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.
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.
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.
No REPAIR the open circuit. CLEAR the DTCs.
REPEAT the self-test.
20 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) - 2.3L REMOVAL/INSTALLATION .
REPEAT the PCM Quick Test. See PCM QUICK TEST  .
No If any other DTC is present, GO to applicable DTC inspection.
If no DTC is present, troubleshooting complete.
RENDER: 1.0x

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