P0838
Four Wheel Drive (4WD) Switch Circuit Low
This code indicates four wheel drive (4wd) switch circuit low. It relates to the transmission / transfer case / hybrid-ev drive systems and may affect performance, emissions, or drivability depending on the exact failure.
Four Wheel Drive (4WD) Switch Circuit Low
Common causes
- medium
Low or degraded transmission fluid
Low fluid level or old fluid can cause shifting and pressure faults.
Typical part cost: $100-400
- medium
Faulty sensor or solenoid
Transmission sensors and solenoids commonly fail and set codes.
Typical part cost: $100-400
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P0838 mean?
P0838 means "Four Wheel Drive (4WD) Switch Circuit Low". It is a generic OBD-II code that points to a fault in the transmission / transfer case / hybrid-ev drive systems.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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