P0848
Transmission Fluid Pressure Sensor/Switch B Circuit High
Transmission / fluid pressure
Generic OBD-II
Medium
What it means
P0848 means the transmission controller sees an abnormally high voltage on the fluid pressure sensor/switch "B" circuit, usually from an open or a short-to-power in the wiring. The engine starts and runs, but with a bad pressure signal the transmission may shift irregularly or drop into a protective limp mode until the circuit is repaired.
Medium
Can I keep driving? The engine runs, but shifts may be harsh, delayed, or the transmission may enter limp mode — have it diagnosed before hauling or long trips.
Common symptoms
What you'll notice
- Check-engine light on
- Harsh or delayed shifting
- Irregular shifting or transmission stuck in a fail-safe gear
- Reduced fuel efficiency
Common causes
Most likely first
- Faulty transmission fluid pressure sensor/switch (B)Likely
- Open circuit or short-to-power in the sensor wiringCommon
- Loose or corroded connector at the sensorCommon
- Failed control module (rare — check wiring first)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and note when the high reading occurs.
- Inspect the pressure sensor connector and wiring for opens, shorts, or corrosion.
- Compare the sensor's reported pressure to actual line pressure with a scan tool/gauge.
- Repair wiring/connector faults, then replace the pressure sensor/switch if it still reads high. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0848?+
Brief driving is usually okay, but harsh shifting or limp mode can strain the transmission. Get it looked at soon.
Can I just clear P0848?+
It comes back until the sensor circuit is repaired. Clearing only resets the light.
Related codes
Often seen with P0848
Read & clear P0848 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX