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DTC P1633: Battery Overcharge: Testing

NOTE: Check for service bulletins and on-line information.
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. Turn ignition on. Using scan tool, monitor ALTT V and B+ PIDs. Start engine. If ALTT V PID is more than 18.5 volts and B+ PID is less than 16 volts, go to next step. If ALTT V PID is 18.5 volts or less, problem is intermittent. See TROUBLE SHOOTING - NO CODES article.
  2. Disconnect generator connector. Check generator harness connector and generator terminals. If problems are not present, go to next step. If any problems are present, repair as necessary. Go to step  7 .
  3. Turn ignition on. Check voltage between generator harness connector terminal "D" (White/Red wire) and ground. If battery voltage is present, go to next step. See WIRING DIAGRAMS article. If battery voltage is not present, problem is at generator. Go to step  6 .
  4. Turn ignition off. Disconnect PCM connector. PCM is mounted to passenger floor, behind glove box. Check connector and PCM terminals. If problems are not present, go to next step. If any problems are present, repair as necessary. Go to step  7 .
  5. Turn ignition on. Check voltage between generator harness connector terminal "D" (White/Red wire) and ground. 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 harness connector terminal No. 53 and generator harness connector terminal "D". See Figure . See WIRING DIAGRAMS article. Go to step  7 .
  6. Check voltage between generator terminal "D" and ground. If battery voltage is not present, go to next step. If battery voltage is present, replace generator. Go to next step.
  7. Reconnect all components. Turn ignition off, then on. Recheck DTCs. If same DTC is present, replace PCM and go to next step. If same DTC is not present, go to next step.
  8. 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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