P0779 code meaning
Pressure Control Solenoid B Intermittent
Powertrain system Generic code P07xx codes Check engine light
What P0779 means
Pressure control solenoids are current-controlled proportional valves, and what B and C mean depends on the design: on GM's clutch-to-clutch automatics they are the pressure valves of clutches 2 and 3, on GM's CVT B is primary pulley pressure and C line pressure, on Jatco CVTs B is the secondary pressure valve, on Saab's AF40 B and C are clutch valves SLC1/SLC2. In J2012 P0779 is an intermittent fault of valve B. The only manufacturer use found differs: Mitsubishi's 2022 Jatco CVT sets P0779 for an open circuit or short to positive in the secondary pressure valve circuit after 1 s (short to ground is P0778). The transmission then engages harshly, accelerates weakly and does not lock up.
P0779 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor1 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0779
- Harsh engagement at times
- Weak acceleration, no lock-up
- Check engine light
Common causes of P0779
- Most likelyConnector or wire open or loose contact
- PossibleShort to positive in the harness
- PossibleValve coil faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Pressure control solenoidTransmission valve bodyTransmission clutchesTransmission control module
What each part of P0779 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 7 | Area: transmission. |
| 79 | The exact fault in that area. |
What to do next
- Note P0779 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0779
What does P0779 mean?
P0779 means "Pressure Control Solenoid B Intermittent". Pressure control solenoids are current-controlled proportional valves, and what B and C mean depends on the design: on GM's clutch-to-clutch automatics they are the pressure valves of clutches 2 and 3, on GM's CVT B is primary pulley pressure and C line pressure, on Jatco CVTs B is the secondary pressure valve, on Saab's AF40 B and C are clutch valves SLC1/SLC2. It is a generic code, so it means the same on every make.
Is it safe to drive with P0779?
Drive gently and only to a workshop. With P0779 the car can go into limp mode (reduced power) to protect itself.
Will P0779 fail an emissions test?
Yes, it can. P0779 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0779 to fix?
Difficulty: medium. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P0779 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.