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Home >> Mazda >> 2003 >> MPV ES >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1633: Battery Overcharge >> Diagnostic Procedures
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Diagnostic Procedures

CAUTION: DO NOT crank engine before replacement PCM is programed to immobilizer system or PCM will be severely damaged. If test procedures require replacement of PCM on a vehicle equipped with immobilizer system, vehicle must be sent to authorized Mazda dealer to have replacement PCM programed.
  1. Check for service bulletins and on-line information. Repair as necessary. After repair, go to next step.
  2. Inspect Poor Connection Of Generator Connector -  Disconnect generator 3-pin harness connector. Check for damaged, loose or corroded terminals. If no problem is found, go to next step. If problem is present, repair terminal or connector as necessary. After repair, go to step  7.
  3. Classify Generator Malfunction Or Other Malfunction -  Turn ignition on, engine off. Check voltage between ground and generator 3-pin harness connector terminal "D" (White/Red wire). See Figure. If battery voltage is present, go to next step. If battery voltage is not present, problem is at generator. Go to step  6.
  4. Inspect Poor Connection Of PCM Connector -  Turn ignition off. Disconnect PCM 104-pin harness connector. Check for damaged, loose or corroded terminals. If no problem is found, go to next step. If problem is present, repair terminal or connector as necessary. After repair, go to step  7.
  5. Inspect Generator Control Circuit For Short To Power -  Turn ignition on, engine off. Measure voltage between ground and generator 3-pin harness connector terminal "D" (White/Red wire). If battery voltage is not present, go to step  7. If battery voltage is present, repair short to power in White/Red wire between PCM 104-pin harness connector terminal No. 53 and generator 3-pin harness connector terminal "D". See Figure and Figure . See appropriate wiring diagram under ENGINE PERFORMANCE in WIRING DIAGRAMS. After repair, go to step  7.
  6. Inspect Generator Control Terminal For Short To Power -  Measure voltage between ground and generator 3-pin harness connector terminal "D" (White/Red wire). If battery voltage is not present, go to next step. If battery voltage is present, replace generator. After repair, go to next step.
  7. Verify Trouble Shooting Of DTC P1633 Completed -  Reconnect all components. Turn ignition off, then on, engine off. Recheck DTCs. If DTC P1633 is present, replace PCM. After repair, go to next step. If DTC P1633 is not present, go to next step.
  8. Verify After Repair Procedure -  Using scan tool, perform after repair procedure. See AFTER REPAIR PROCEDURE . If DTC is not present, testing is complete. If any DTC is present, go to appropriate test for diagnosis and repair.
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