P079C
Transmission Friction Element C Slip Detected
Transmission / internal (clutch)
Generic OBD-II
High
What it means
P079C means the transmission control module detected friction element "C" — one of the internal clutch packs or bands — slipping instead of holding its gear solidly. Slip is one of the more damaging conditions a transmission can report: it generates heat and wears the clutch material fast, so it should be addressed quickly rather than driven on.
High
Can I keep driving? Drive as little as possible — a slipping friction element builds heat and wears fast, and extended driving can ruin the transmission. Get it checked promptly.
Common symptoms
What you'll notice
- Slipping or jerking when shifting gears
- Delayed or erratic shifting
- Transmission running hot
- Higher-than-expected engine RPM for the gear
- Check-engine light on
Common causes
Most likely first
- Low transmission fluid levelLikely
- Worn or damaged friction element (clutch pack) CCommon
- Faulty solenoid or valve not applying the element with enough pressureCommon
- Wiring or sensor faults feeding bad data to the moduleLess often
- Internal mechanical wear or damage in the transmissionLess often
How to diagnose & fix
Work through it in order
- Check transmission fluid level and condition first; if low or dirty, service it with the specified fluid.
- Inspect the pan and filter for clutch material or metal debris, and replace a clogged filter.
- Verify apply pressure and test the solenoids/valve body controlling friction element C.
- Check and adjust transmission bands for proper tension where applicable.
- If pressures are correct, the friction element/clutch plates are worn and the transmission needs teardown or overhaul. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P079C?+
Not for long. A slipping clutch pack overheats and wears quickly, so keep driving to a minimum and get it diagnosed before the damage spreads.
Can I just clear P079C?+
You can, but it returns as soon as the element slips again. Clearing it without fixing the fluid, pressure, or worn clutch just hides worsening damage.
Related codes
Often seen with P079C
Read & clear P079C 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