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Diagnostic Procedures

  1. If QUICK TEST was not performed, go to QUICK TEST  under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
    NOTE: Verify A/C and defrost were off during Self-Test. If A/C or defrost were on, turn system off and rerun Self-Test.

  2. DTC P1464: Check ACCS PID

    Ensure A/C and defrost are turned off. With KOEO, using scan tool, select Diagnostic Data Link. Select PCM. Select PID/Data Monitor and Record. Access and observe ACCS PID. If ACCS PID is on, go to next step. If ACCS PID is off, ACCS PID indicates ACCS input to PCM is low. Verify test results. With A/C and defrost off, rerun Self-Test where DTC P1464 was received. Go to step  7 .

  3. ACCS PID On: Disconnect A/C Cycling Switch & Check If ACCS PID Turns Off

    Turn ignition off. Disconnect A/C cycling switch. With KOEO, using scan tool, select Diagnostic Data Link. Select PCM. Select PID/Data Monitor and Record. Access and observe ACCS PID. If ACCS PID is on, go to next step. If ACCS PID is off, verify operation of A/C demand switch. If A/C demand switch is okay, repair short to power in A/C demand circuit to A/C cycling switch. See Fig 1 . See WIRING DIAGRAMS article. Go to step  7 .
    Fig 1: Identifying A/C Circuits
    G00155556Courtesy of MAZDA MOTORS CORP.

  4. Check Power To A/C Clutch Circuit For Short To Power

    Turn ignition off. Disconnect A/C clutch relay. With KOEO, measure voltage between A/C clutch power circuit (Gray/White wire) in harness connector and chassis ground. See Fig 2 . Turn ignition off. If voltage is less than one volt, go to next step. If voltage is one volt or more, repair short to power. See WIRING DIAGRAMS article. Go to step  7 .
    Fig 2: Identifying A/C Clutch Relay Circuits
    G00155555Courtesy of MAZDA MOTORS CORP.

  5. Check ACCS Circuit For Short To Power

    Turn ignition off. Disconnect PCM connector. Install breakout box, leaving PCM disconnected. With KOEO, measure voltage between breakout box terminals No. 41 (ACCS circuit) and 103 (PWR GND circuit). Turn ignition off. If voltage is less than one volt, go to next step. If voltage is one volt or more, repair ACCS short circuit to power. See WIRING DIAGRAMS article. Go to step  7 .

  6. Check ACCS Circuit Voltage To PCM With A/C Clutch Relay Connected

    Reconnect A/C clutch relay. With KOEO, measure voltage between breakout box terminals No. 41 (ACCS circuit) and 103 (PWR GND circuit). Turn ignition off. If voltage is less than one volt, replace faulty PCM. Go to next step. If voltage is one volt or more, replace faulty A/C clutch relay. Go to next step.

  7. Verify Trouble Shooting Of DTCs Completed

    Reconnect all electrical connectors. Using scan tool, clear DTC memory. Using scan tool, retrieve DTCs. See QUICK TEST  under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM and repeat QUICK TEST  under SELF-DIAGNOSTIC SYSTEM. If any other DTC is present, go to applicable procedure for other DTCs. See DIAGNOSTIC TROUBLE CODE DEFINITIONS  . If no DTCs are set, trouble shooting is complete.
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