P079D
Transmission Friction Element D Slip Detected
Transmission
Generic OBD-II
High
What it means
P079D sets when a friction element inside the transmission — a clutch pack or band identified as "element D" — slips instead of holding as commanded. The control module sees the element not gripping, and continued driving overheats and wears the transmission. Common causes are low or degraded fluid, low line pressure, or a worn friction element.
High
Can I keep driving? Not recommended — a slipping friction element overheats and wears the transmission quickly; minimize driving until it's repaired.
Common symptoms
What you'll notice
- Jerking or hesitation while accelerating
- Slipping gears — engine revs climb without matching road speed
- Difficulty shifting
- Transmission overheating
- Burning smell from the transmission
Common causes
Most likely first
- Low or contaminated transmission fluidLikely
- Worn or damaged friction element / clutch platesCommon
- Failing solenoid or poor line-pressure controlCommon
- Sensor or wiring fault reporting the slipLess often
- Internal mechanical wear inside the transmissionLess often
How to diagnose & fix
Work through it in order
- Check transmission fluid level and condition; flush and refill with the correct fluid if it's low, burnt, or dirty.
- Read freeze-frame data and note any companion friction-element or pressure codes.
- Inspect and replace the transmission filter if clogged or damaged.
- Check line pressure and solenoid operation.
- If the friction element is worn, the transmission needs internal repair or overhaul.
FAQ
Quick answers
Is it safe to drive with P079D?+
No — a slipping friction element generates heat and wears fast. Minimize driving and get it inspected before it causes major damage.
Can I just clear P079D?+
Clearing won't stop the slip; it returns quickly and driving in the meantime accelerates wear. Fix the fluid, pressure, or worn element.
Related codes
Often seen with P079D
Read & clear P079D 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