P0815
Upshift Switch Circuit
Transmission / driver controls
Generic OBD-II
Low
What it means
P0815 means the transmission control module detected a fault in the upshift switch circuit — the switch or paddle that lets the driver command an upshift in manual or sport mode. It generally only affects manual shifting; the transmission still changes gears automatically. The usual cause is the switch itself or its wiring rather than the transmission.
Low
Can I keep driving? Safe to drive — the transmission still shifts automatically; you just lose the manual upshift command until it's fixed.
Common symptoms
What you'll notice
- Manual upshift requests ignored
- Manual / sport shift mode unavailable
- Check-engine light on
- Transmission defaults to automatic shifting only
Common causes
Most likely first
- Faulty upshift switchLikely
- Wiring or connector fault in the switch circuitCommon
- Loose or corroded electrical connectionsCommon
- Failed transmission control module (TCM)Less often
How to diagnose & fix
Work through it in order
- Inspect the upshift switch and its connector for damage or corrosion.
- Test switch continuity when pressed and released.
- Check the wiring between the switch and the TCM for opens or shorts.
- Replace the upshift switch if it fails the continuity test.
- Confirm the repair with a scan tool. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0815?+
Yes. The transmission still shifts on its own in automatic mode — you just can't command manual upshifts until the switch circuit is repaired.
Can I just clear P0815?+
You can, but it returns until the switch or wiring is fixed, since the TCM keeps monitoring the circuit.
Related codes
Often seen with P0815
Read & clear P0815 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