OBD-II FAULT CODE
B1838

Battery Saver Power Relay Circuit Failure

Reference information for B1838. Because this is manufacturer-specific, confirm the exact definition for the vehicle before using the diagnostic guidance below.

Manufacturer-specific code

This code can have different meanings depending on vehicle make, model and year. Treat the definition below as a reference and confirm it with OEM service information before diagnosis or repair.

BodySystem
Power supply / chargingCategory
HighSeverity
  • Body/accessory warning lamp or feature not working
  • Weak battery
  • Charging system fault
  • Loose/corroded terminals
  • Poor ground
  • Check related fuses, connectors, grounds and switch/module power supply
  • Test battery state of charge and charging voltage
  • Inspect terminals and ground straps
  • Clean/tighten terminals, replace weak battery, repair alternator/charging circuit as needed
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Disclaimer: Information is provided for general guidance only and may not apply to all vehicles. Always consult a qualified technician.