P0779
Pressure Control Solenoid B Intermittent
Transmission / pressure control
Generic OBD-II
Medium
What it means
P0779 means the transmission control module saw an intermittent fault in the pressure control solenoid "B" circuit — the signal drops out or goes out of range now and then rather than constantly. Because it comes and goes, the most common culprit is a loose or corroded connector or chafed wiring rather than the solenoid itself.
Medium
Can I keep driving? Usually drivable — the fault comes and goes, so shifting may be normal most of the time with occasional harsh or slipping shifts. Get it fixed before it becomes constant.
Common symptoms
What you'll notice
- Occasional harsh, firm, or delayed shifts
- Intermittent slipping or flaring between gears
- Check-engine light that may come and go
- Brief drops into limp mode that clear on restart
Common causes
Most likely first
- Intermittent open or short in the solenoid B wiring or connectorLikely
- Loose or corroded electrical connection at the solenoidCommon
- Failing pressure control solenoid BCommon
- Failed transmission control module (TCM)Less often
How to diagnose & fix
Work through it in order
- Scan for codes and read freeze-frame data to capture the conditions when it sets.
- Because the fault is intermittent, focus on the wiring — wiggle-test the harness and connector while watching for a signal drop.
- Inspect the solenoid connector for corroded, spread, or backed-out pins and repair as needed.
- Check transmission fluid level and condition, and test the solenoid's resistance against spec.
- If wiring and solenoid are good, suspect the TCM. Clear and re-test with a road test.
FAQ
Quick answers
Is it safe to drive with P0779?+
Usually yes for short trips, since the problem is intermittent — but harsh or slipping shifts stress the transmission, so don't ignore it.
Can I just clear P0779?+
It will clear, but an intermittent wiring or solenoid fault brings it back. Tracking down the loose or corroded connection is the real fix.
Related codes
Often seen with P0779
Read & clear P0779 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