P0797 OBD-II Trouble Code: Pressure Control Solenoid C Stuck On

Our certified mechanics come to you · 12-month, 12,000-mile warranty

SCHEDULE P0797 DIAGNOSTIC Get a fair and transparent estimate upfront
Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0797 code

P0797 is a diagnostic trouble code (DTC) for "Pressure Control Solenoid C Stuck On". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $70.00. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $30.00 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford$70.00$30.00
Toyota$70.00$30.00
BMW$70.00$30.00
SCHEDULE P0797 DIAGNOSTIC Get a fair and transparent estimate upfront

Check Engine Light

P0797 code definition

A P0797 trouble code indicates that the Powertrain Control Module (PCM) has detected a problem in one of the electronic pressure control solenoids or solenoid circuits. Found in automatic transmissions, electronic pressure control solenoids receive their instructions from the PCM.

When diagnosing a P0797 trouble code, the mechanic should also look for codes P0795, P0796, P0798, and P0799.

What the P0797 code means

Using calculations based on the load on the engine, engine speed, vehicle speed, and throttle position, the PCM determines how much pressure the hydraulic pump should apply to the transmission. When there is a discrepancy between the amount of pressure applied and the amount desired, a P0797 trouble code is stored.

What causes the P0797 code?

Some common causes of a P0797 trouble code include:

  • A bad electronic pressure control solenoid
  • Low and/or dirty transmission fluid
  • Transmission failure
  • A faulty PCM or TCM
  • A faulty hydraulic pump or hydraulic line blockage within the transmission

What are the symptoms of the P0797 code?

Symptoms of a P0797 trouble code include disabled shift functioning, failure of the torque converter to engage, harsh shifting, and transmission slippage and overheating. In addition, the vehicle could experience a decrease in fuel efficiency.

How does a mechanic diagnose the P0797 code?

To diagnose a P0797 trouble code, the mechanic needs a code reader, manual pressure gauge, hydraulic pressure diagram, and a digital volt/ohmmeter. The mechanic also needs to perform the following steps:

  • Start by pulling the transmission dipstick to check fluid level and condition

  • When examining the transmission fluid, look for abnormal looking or burnt smelling fluid

  • If the fluid looks strange or smells burnt, drop the transmission pan and look for evidence of debris. This signifies a damaged transmission, requiring the mechanic to rebuild it

  • The mechanic should also fill the transmission fluid to a level to allow them to detect any leaks

  • Once any leaks have been found and repaired and the transmission rebuilt if damaged, the mechanic should fill the transmission fluid to a normal level and start the vehicle, allowing the engine to reach a normal operating temperature

  • Clear the P0797 trouble code and test drive the vehicle to see if the code persists

  • Examine the wiring, connectors, and components for fault or damage. This usually requires the replacement of the entire internal transmission harness by the mechanic

  • If after clearing the trouble code it returns, connect the scanner to the diagnosis connector and download any stored codes and freeze frame data

  • Using a hydraulic pressure diagram, hook a manual pressure pump to the transmission and check the pressure produced by the hydraulic pump against the manufacturer's specifications

  • If the code returns, use the digital volt/ohmmeter to check the reference voltage and ground signal of the electronic pressure control solenoid that is producing the trouble code

  • If the reference voltage or ground signal is open, check the continuity and resistance of all related circuits. The mechanic should make sure to disconnect any control module son the circuit to avoid damage and memory loss

  • If everything checks out and the code returns after clearing, test the PCM for fault

  • Clear the P0797 trouble code and test the system to see if it returns

Common mistakes when diagnosing the P0797 code

A common mistake is for a mechanic to replace the high pressure pump when the problem actually lies with the electronic pressure control solenoid or faulty wiring. In cases such as this, the problem is not repaired and the trouble code returns.

How serious is the P0797 code?

The causes of a P0797 trouble code can lead to problems with shifting, malfunction of the transmission and torque converter, and a reduction in overall fuel efficiency.

What repairs can fix the P0797 code?

To repair a P0797 trouble code, the mechanic needs to take the following steps:

Need help with a P0797 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

P0797
trouble codes
Check Engine Light

Fast and easy Check Engine Light is on Inspection service at your home or office.

SCHEDULE P0797 DIAGNOSTIC
Get a fair and transparent estimate upfront

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.5/5

Number of Reviews

3,578

Rating Summary
3,265
157
41
23
92
3,265
157
41
23
92

Tien

20 years of experience
746 reviews
Tien
20 years of experience
Good guy. I have used him before.
2000 VOLKSWAGEN PASSAT - CHECK ENGINE LIGHT IS ON - SAN RAMON, CALIFORNIA

Diego

18 years of experience
208 reviews
Diego
18 years of experience
he arrived early to my home and started out by doing an inspection of my vehicle he explained how the procedures he checked to see if everything was ok he went through wiring diagrams to check the wiring on my egr valve. he was proffesional about his identifying the check engine light your mechanic is convenient and I would most likely reccomend to anyone.
2008 CHEVROLET EQUINOX - CHECK ENGINE LIGHT IS ON - PHOENIX, ARIZONA

Peter

33 years of experience
346 reviews
Peter
33 years of experience
Good overall
1999 BMW 323I - CHECK ENGINE LIGHT IS ON - PHOENIX, ARIZONA

Keith

15 years of experience
168 reviews
Keith
15 years of experience
Keith is the best mechanic I have ever had the please of doing business with. He is EXTREMELY professional, knowledgeable and honest. There weren't any gimmicks or fast talk. I expected my car to be fixed and be on my way, except I received more than that. I was thoroughly (and patiently) educated on the issues my car was experiencing and why it effected the functionality of a smooth drive. I previously saw three mechanics before Keith and nothing came to fruition except wasted dollars. I erroneously selected the parts that needed to be fixed based on the previous mechanics recommendation. However, Keith was able to isolate the real problem and ordered the correct part. If you're looking for your car to be really fixed, pick Keith. I almost went with other mechanics that's been using this service longer and I'm so ecstatic that I did not. Everyone is looking for a cheap mechanic but they just patch up your car enough so that you have to keep returning. Keith's qualuty of work is worth the price and he's reasonable. Take my advice and have him inspect your vehicle first to find the real issue. I don't know a lot about cars but I know about integrity, hard honest work and awesome customer service. That's what you will experience booking with Keith. A++
2013 HONDA CIVIC - CHECK ENGINE LIGHT IS ON - KISSIMMEE, FLORIDA

More related articles

How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Get a Louisiana Driver's Permit
s licensing program. The first step in this program is to obtain...

Related questions

Q: 2 major issues

The code P0453 is for the purge control valve; it's most likely bad and needs to be replaced. The ticking noise is possibly the oil pressure dropping too low at idle and the camshaft followers are getting noisy. Have the...

Q: My check engine light is on after getting into a wreck last night in my 1995 Ford Thunderbird

If the check engine light is on then the computer needs to be scanned for codes. The codes will give clues as to what is causing this to occur. It may be related to the accident or it may be...

Q: Throttle body position sensor

The rumbling noise may be coming from the loose catalyst in the exhaust piping. It would need to be verified by a road test to listen to the noise. If the catalyst is breaking up in the exhaust then the...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1-800-701-6230 · hi@yourmechanic.com