P0775: Pressure Control Solenoid B Malfunction (Meaning, Causes, Fixes)
What P0775 means
An automatic transmission changes gears by applying clutches and bands with fluid pressure. The control module uses pressure control solenoids to set that pressure in each hydraulic circuit at the right moment. RepairPal says the transmission control module (TCM) sets P0775 when it detects that a pressure control solenoid is not performing as desired. OBD-Codes.com says the powertrain control module (PCM) sets it when pressure control solenoid B has a general malfunction. P0775 is the general code for the B solenoid; the more specific codes in the same family are P0776 (performance or stuck off), P0777 (stuck on), P0778 (electrical) and P0779 (intermittent) (OBD-Codes.com, RepairPal). It is a generic OBD-II code that OBD-Codes.com says shows up on Ford, Lincoln, Mercury, Chevrolet, Toyota, Nissan, Allison/Duramax, Dodge, Jeep, Honda, Acura and other vehicles, but the exact test values and repair steps vary by transmission, so the vehicle's service information should come first.
Severity: can I keep driving?
Stop and fix promptly
Get it checked soon. RepairPal rates P0775 Urgent, meaning it can cause severe damage or be unsafe. OBD-Codes.com calls it moderate at first but says it can get worse quickly if it isn't fixed. The transmission may slip, overheat or drop into limp mode, so avoid hard acceleration, towing and long trips until it's diagnosed, and get off the road safely if it suddenly loses drive.
Common symptoms
- Check engine light on (OBD-Codes.com)
- Transmission may not shift properly (RepairPal); OBD-Codes.com describes slipping when shifting or catching in gear
- Vehicle goes into limp mode (OBD-Codes.com)
- Transmission overheating (OBD-Codes.com)
- Lower fuel economy (both sources)
- Possibly misfire-like symptoms (OBD-Codes.com)
Likely causes
Roughly most to least common, based on the sources below. Your vehicle may differ.
- Failed pressure control solenoid (both sources)
- Low transmission fluid (RepairPal), or dirty or contaminated fluid (OBD-Codes.com)
- Dirty or clogged transmission filter (OBD-Codes.com)
- Wiring problem, or a corroded or damaged connector (both sources)
- Faulty transmission control module (RepairPal) or PCM (OBD-Codes.com)
- Defective transmission pump, defective valve body or restricted hydraulic passages (OBD-Codes.com)
- The sources differ: RepairPal lists only the module, low fluid, the solenoid and wiring, while OBD-Codes.com adds fluid contamination, the filter, the pump, the valve body and blocked passages. They also disagree on severity, with RepairPal rating it Urgent and OBD-Codes.com calling it moderate at first, and they name different computers (TCM versus PCM) as the one that sets the code
Diagnostic steps you can do
Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.
- Read all stored codes and freeze frame data before clearing anything; a more specific B solenoid code (P0776 to P0779) or other transmission codes can point to the real cause.
- Check for technical service bulletins (TSBs) for your vehicle, year and transmission; OBD-Codes.com says this can save a lot of time.
- Check the transmission fluid level and condition using the procedure in your owner's or service manual, and look for burnt smell, dark color or debris.
- Check your records for when the fluid and filter were last changed (OBD-Codes.com).
- Inspect the wiring and connectors to the transmission pressure control solenoids, the pump (if electric) and the computer for damage, corrosion, loose connections or damaged pins.
- Further testing needs a digital multimeter and your vehicle's specific voltage and pressure specs; OBD-Codes.com says wiring should normally read 0 ohms with the power off unless the service data says otherwise.
Typical fixes
- Top up, or change the fluid and filter (both sources point to fluid)
- Replace the faulty pressure control solenoid
- Clean corroded connectors or repair damaged wiring
- Flush the transmission to clear restricted passages (OBD-Codes.com)
- Repair or replace the valve body or transmission pump if diagnosis points there (OBD-Codes.com)
- Reflash or replace the transmission or engine control module (both sources list the module)
Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.
🛠 When to call a pro
- The transmission is slipping, overheating or stuck in limp mode
- The fluid is burnt or full of debris
- The fluid level and wiring check out and the code comes back
- Testing needs pressure gauges, a scan tool or removing the pan and valve body
- OBD-Codes.com warns this code can be misdiagnosed as an engine misfire, a transmission pump problem, an internal transmission problem or a driveline problem, so a proper diagnosis matters before buying parts
Where to buy
Plain search links. Always match parts to your exact year, make, model and engine.
FAQs
Is P0775 serious?
Treat it as serious. RepairPal rates it Urgent. OBD-Codes.com says it usually starts as moderate but can get worse quickly, with slipping, overheating and limp mode possible.
What's the difference between P0775 and P0776?
Both point at pressure control solenoid B. P0775 is the general malfunction code, while P0776 specifically means the solenoid's performance is off or it is stuck off (OBD-Codes.com, RepairPal).
Can low transmission fluid cause P0775?
Yes. RepairPal lists low fluid as a common cause, and OBD-Codes.com lists dirty or contaminated fluid and a clogged filter, so checking the fluid is the first step.
How much does it cost to fix P0775?
Neither source gives a repair cost. It can range from a fluid service or wiring repair to a new solenoid, valve body or control module, so get a diagnosis and a written estimate first.
Sources
Last reviewed 2026-10-25. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.