P0900
Clutch A Actuator Control Circuit/Open
Transmission / automated clutch
Generic OBD-II
High
What it means
P0900 means the transmission control module detects an open circuit in the control wiring for clutch actuator A. On automated-manual and dual-clutch transmissions this actuator engages and releases the clutch, so an open circuit can stop the car from moving or cause it to stall. The engine itself still starts, but the vehicle may be undriveable until the actuator circuit is repaired.
High
Can I keep driving? The engine starts, but an open clutch actuator can prevent the car from moving or cause stalling — have it towed or repaired before driving.
Common symptoms
What you'll notice
- Check-engine light on
- Difficulty shifting or the transmission won't engage a gear
- Stalling when coming to a stop or setting off
- Vehicle may not move or enters a fail-safe mode
Common causes
Most likely first
- Open or damaged wiring in the clutch actuator control circuitLikely
- Loose or corroded connectors at the actuatorCommon
- Failed clutch actuatorCommon
- Failed transmission control module (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and inspect the clutch actuator connector and wiring for an open circuit, damage, or corrosion.
- Measure the actuator's control circuit for continuity and correct resistance with a multimeter.
- Confirm the actuator receives its command signal and ground when a shift is requested.
- Replace the clutch actuator if it is open or unresponsive with wiring confirmed good. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0900?+
No. On an automated clutch, an open actuator circuit can leave the car unable to move or stalling in traffic, so have it repaired before driving.
Can I just clear P0900?+
It will clear, but an open control circuit returns immediately until the actuator or wiring is repaired.
Related codes
Often seen with P0900
Read & clear P0900 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