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2019 MAZDA MAZDA3

2.5L I4FWDAUTOMATICgas
6 active safety recalls on this vehicle — view recalls
Repairs0Labor479Torque3805Fluid6DTC919Battery0Maintenance0Recalls6
P1633low severityPowertrain

KAM Voltage Too Low

on 2019 Mazda Mazda3 2.5L I4 · FWD

What this code means

The PCM has detected that the Keep Alive Memory voltage is too low to maintain stored data. The PCM will lose adaptive values and must relearn when power is restored.

Symptoms

  • Check Engine Light
  • Loss of adaptive fuel trim values
  • Rough idle after restart
  • Transmission relearning shift points

Common causes

  • Discharged battery
  • Corroded battery cables
  • Excessive parasitic drain
  • Blown KAM fuse
  • Faulty PCM power relay

Diagnostic steps

  1. Test battery voltage with key off (should be above 12.4V)
  2. Inspect battery terminals for corrosion
  3. Check KAM fuse
  4. Test for parasitic drain
  5. Check PCM power relay

Repair notes

Clean battery terminals; replace the battery if discharged; repair the KAM power circuit.

Other Powertrain codes on this vehicle

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