Transmission Fluid Pressure Sensor/Switch C Circuit Intermittent
What it means
P0874 means the transmission's "C" fluid-pressure sensor circuit is dropping out intermittently — the signal comes and goes rather than failing outright. The engine runs normally, but the controller loses a valid pressure reading now and then, which can cause occasional harsh shifts, slipping, or brief limp mode. Intermittent faults usually trace to a loose connector or chafed wiring, so wiggle-testing the harness is the key step.
Can I keep driving? Usually drivable, but intermittent harsh or slipping shifts stress the transmission — get it checked before the fault becomes constant.
Common symptoms
What you'll notice
- Check-engine light on (may come and go)
- Harsh or delayed shifting that comes and goes
- Occasional transmission slipping
- Transmission may briefly enter limp mode
Common causes
Most likely first
- Loose, corroded, or intermittent connector at the sensor 'C'Likely
- Chafed or intermittently shorting/open wiring in the circuitCommon
- Faulty transmission fluid pressure sensor/switch 'C'Common
- Low or dirty transmission fluidLess often
- Failed transmission control module (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data to capture the conditions when the fault appears.
- Wiggle-test the sensor 'C' connector and harness while watching for dropouts.
- Inspect for corrosion, chafing, and loose pins; repair intermittent connections.
- Check fluid level and condition, then test the sensor's signal against spec.
- Replace the pressure sensor/switch if it drops out, then clear and road-test.
FAQ
Quick answers
Is it safe to drive with P0874?+
Can I just clear P0874?+
Related codes
Often seen with P0874
Read & clear P0874 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.