P0799 - OBD Trouble Code

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This OBD-II code is a generic one and shows an error with the electronic pressure control solenoid. The issue could possibly also be with the entire solenoid circuit too. In general, the P0799 code mainly shows a signal issue with the circuit/ multiple solenoid, here it specifically is detecting an error with the “C” solenoid. The Powertrain Control Module (PCM) in automatic transmissions, uses the data from various sources like engine speed, vehicle speed, throttle position, and engine load to be able to determine the exact hydraulic pressure present in the transmission. This hydraulic pressure is responsible for shifting transmission gears and also aiding the torque converter lockup.

The PCM send this data it has collected to the pressure control solenoids. Which is used to regulate the hydraulic pressure. When the PCM is able to detect that there’s an incongruence between the actual pressure level and the ideal pressure level then it will set the code P0799. The check engine light may also get illuminated.

The Auto Transmission Control Module (TCM) uses Pressure Control Solenoids so that it can control the hydraulic pressure in the transmission. This hydraulic pressure is important, as because of it the various clutch packs in the transmission are applied. These clutch packs in turn provide different gear ratios which are needed to efficiently propel the vehicle on road. If the TCM is detecting any pressure control solenoid issues, it will set the P0799 code.

What causes this problem with the Pressure Control Solenoid C Intermittent?

• Defect of the pressure control solenoid
• Not enough transmission fluid
• Contaminated auto transmission fluid
• Damages or fault in the electrical components of the system (wires and connectors)
• Hydraulic blockages found within the fluid passages of the internal transmission
• Defect in the high-pressure pump
• Mechanical failure in the internal transmission
• Defective PCM (rare) or transmission control module

1. Transmission Pressure Control Solenoid - To resolve the P0799 code figure out the issue with the solenoid and try to fix it. If repairing is not resolving the problem opt for a replacement. Parts Avatar has the solution for you, we provide a wide variety of branded car parts, which you can order online from the comfort of your home.
2. Transmission Fluid - Drain out the dirty fluid and replace with new one. If the fluid is good but low, fill it till the level needed. Buy easily from any of the warehouses of Parts Avatar located across Toronto.
3. Transmission Pump - Fix the leaks or damages or replace with a new one and get rid of the P0799 code.
4. Internal Transmission - It’s important to only go for good quality parts for your vehicle. So, don’t compromise and look for the ones compatible with your vehicle on Parts Avatar. We ship to the remotest corners of Canada.
5. Transmission Control Module - Repair and replace the module as per the damages. You can find the best one for your vehicle on Parts Avatar. We offer free shipping on orders over CAD $99.

Willing to know some common symptoms of OBD Code P0799? Your wish is our demand. Have a look at them below:

Common Symptoms

When the P0799 error code is set, it will mostly be accompanied by the check engine light becoming illuminated. Other symptoms you may also note:

• Transmission problems like slippages or overheating
• Harsh shifting of gears
• Inability shift between gears
• Torque converter clutch refuses to engage or disengage
• Low fuel economy

We have listed out some ways which would help you to correct the occurrence of OBD Code P0799. They are mentioned here as follows:

• Replace of pressure control solenoids
• Replace of electrical components in the system
• Replace of high-pressure pumps
• Replace or addition of transmission fluid
• Removal of hydraulic blockages should be removed
• Replacement of the PCM in very rare cases or TCM module

There is no need to get strained if your OBD Code is still flashing up as we are here at your service. Have a look at our superior variety of Pressure Control Solenoid, Transmission Fluid Levels, Transmission Fluid, High Pressure Pump, Internal Transmission, Transmission Control Module and many more. Now all your problems would vanish within no time.

Here are some steps which you should follow in order to diagnose this fault code:

• You will require the standard OBD-II trouble code scanner. Connect it to the diagnostic port of the vehicle and collect all the codes and freeze frame the data, any additional codes present will also have to be recorded. All these additional codes will have to be resolved in their order of occurrence, going step by step is important to diagnose everything properly.
• Now delete the codes, reset the system and go on a test drive to see if the PCM enters readiness mode or if the code is reset. If the former happens then it’s safe to assume that the code is an intermittent one and the condition will have to worsen before accurate diagnosis can be made.
• If the P0799 code has been rest, then it’s time to start the inspections, starting from the transmission fluid. If it’s low, it will have to be filled to the correct level, if the fluid smells burnt, it’s a sign that the transmission was running when the fuel level was less than the desired level and hence must’ve damage the transmission as well. Also check for any contaminants present in the oil, it shouldn’t be of poor quality. If the fluid is heavily contaminated, merely changing it won’t suffice, you may need to rebuild or replace the whole transmission.
• Inspection will now continue on to the electrical components. All the noticed damaged wires, connectors and circuits will have to be repaired or replaced according to the extent of damage.
• Once this is done, the hydraulic pressure system will have to be checked via a manual pressure gauge. The information collected will have to be compared with the one provided by the manufacturer to see if it’s matching. If the pressure is recorded to be lower than required, then there may be a blockage or malfunctioning of the pump, solenoid or regulator. These components will have to be ruled out and fixed accordingly.
• If you’re still unable to find out what the issue is, then the next step would be to inspect the entire internal transmission.
• During the whole process of diagnostic, at every step of repairs and/or replacement the system will have to be rest. If the code returns then the issue has to still be figured out. This will shorten the diagnosis and correction process.

Common Mistakes When Diagnosing the P0799 Code

There are some mistakes done during the diagnosis of P0799 code like:

• Not following the OBD-II diagnostic protocol correctly