p1633 keep alive power voltage too low
P1633 Keep Alive Power Voltage Too Low
- OBD2 Code: P1633
- Description: Keep Alive Power Voltage Too Low
- Definition: This code indicates that the powertrain control module (PCM) has detected a voltage level in the keep alive memory circuit that is below the specified threshold. The keep alive memory stores important data and settings for the vehicle’s operation, and low voltage can lead to loss of this information.
p1633 – Keep Alive Power Voltage Too Low
Severity: Moderate
Common Causes
p1633 – Keep Alive Power Voltage Too Low
Common causes:
- Weak or dead battery
- Faulty alternator
- Poor electrical connections
- Blown fuse related to the keep alive power circuit
- Faulty PCM (Powertrain Control Module)
Common Misdiagnosis
OBD2 Code: P1633
Description: Keep Alive Power Voltage Too Low
Common Misdiagnosis: Replacing the battery or alternator without checking for wiring issues or blown fuses that may be causing the low voltage condition.
Common Diagnostic Steps
OBD2 Code: P1633
Description: Keep Alive Power Voltage Too Low
Common Diagnostic Steps:
- Check the vehicle’s battery voltage and ensure it is fully charged.
- Inspect battery terminals and connections for corrosion or looseness. Clean and tighten as necessary.
- Examine the keep alive memory (KAM) circuit for any blown fuses or damaged wiring.
- Test the alternator output to confirm it is charging the battery correctly.
- Use a multimeter to check for continuity in the KAM circuit from the PCM to the battery.
- If equipped, inspect any aftermarket electrical accessories that may be drawing excessive power when the vehicle is off.
- Clear codes and perform a road test to see if the code returns after repairs are made.