Transmission Fluid Pressure Sensor/Switch C Circuit Low
What it means
P0872 means the transmission control module reads an abnormally low voltage from the "C" fluid-pressure sensor/switch, one of the sensors that report hydraulic line pressure inside the transmission. The engine still runs, but with a low or missing pressure signal the transmission may slip, shift roughly, or run hot. Because slipping and heat can damage the transmission, it's worth diagnosing without much delay.
Can I keep driving? The engine starts and runs, but the transmission may slip, shift harshly, or overheat; keep driving to a minimum until it's checked to protect the transmission.
Common symptoms
What you'll notice
- Check-engine light on
- Transmission slips or won't shift properly
- Harsh or erratic gear changes
- Transmission running hot
Common causes
Most likely first
- Faulty transmission fluid pressure sensor/switch CLikely
- Open or short to ground in the sensor wiring (reads low)Common
- Damaged or corroded connector at the sensorCommon
- Failed transmission control module (TCM)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check transmission fluid level and condition.
- Inspect the pressure-sensor connector and wiring for damage, corrosion, or shorts to ground.
- Compare the sensor's signal voltage against service data; replace the pressure sensor/switch if out of range.
- If wiring and sensor are good, suspect the TCM. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0872?+
Can I just clear P0872?+
Related codes
Often seen with P0872
Read & clear P0872 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.