P0985 - Shift Solenoid "E" Control Circuit Low

P0985 – OBD-II Trouble Code Technical Description

Shift Solenoid "E" Control Circuit Low

What does the fault code mean P0985?

Trouble code P0985 relates to the vehicle's transmission control system. Each DTC (Diagnostic Trouble Code) is a unique identifier for a specific problem or malfunction in the vehicle system. The P0985 code is associated with the torque converter oil pressure control solenoid valve (EPC - Electronic Pressure Control solenoid).

Possible reasons

Possible reasons for this code may include:

1. Solenoid valve (EPC solenoid) fault: This could include broken wiring, a short circuit, or a faulty valve itself.
2. Wiring or connection problems: Poor connections, corrosion, or broken wiring can cause signal transmission problems.
3. Transmission Control Module (TCM) Problems: If the transmission control module is normal, this may also cause the P0985 code to appear.
4. Transmission oil pressure problems: Low transmission oil pressure can cause problems with the solenoid valve.

To accurately determine and eliminate the problem, it is recommended to contact a car service center or dealer. Technicians will be able to conduct detailed diagnostics using specialized equipment and determine the specific reasons why the P0985 code appears in your vehicle.

What are the symptoms of a fault code? P0985?

Trouble code P0985 indicates problems with the transmission's torque converter oil pressure control solenoid valve. Symptoms associated with this code can vary depending on the specific problem, but they typically include the following:

1. Gearshift problems: You may notice delays, difficulty, or unusual jerking when shifting gears. This may manifest itself as longer shift times or jerky shifts.
2. Idle transmission (Limp mode): If a serious problem is detected, the transmission control system can put the vehicle into a limp mode, which will limit top speed and prevent further damage.
3. Unusual sounds or vibrations: Malfunctions of the solenoid valve may result in unusual sounds or vibrations in the transmission area.
4. Check Engine Light: The Check Engine light on your dashboard illuminates, indicating there is a problem and may be accompanied by a P0985 code.

If you experience these symptoms or if your Check Engine Light comes on, it is recommended that you contact an automotive repair professional to diagnose and repair the problem.

How to diagnose a fault code P0985?

To diagnose DTC P0985, we recommend following these steps:

1. Scanning trouble codes: Use a diagnostic scanner to read trouble codes in the electronic engine management system. If the P0985 code is present, this will be the key point to start diagnosing.
2. Checking connections and wiring: Check all electrical connections associated with the torque converter oil pressure control solenoid valve. Make sure all connections are tight, clean and free of corrosion. Conduct a visual inspection of the wires for damage.
3. Resistance measurement: Using a multimeter, measure the resistance of the solenoid valve. The resistance must meet the manufacturer's specifications. If the resistance is outside the acceptable limits, this may indicate a valve failure.
4. Checking oil pressure: Check the transmission oil level and pressure. Low oil pressure may be causing the problem. Make sure the oil level is within normal limits and replace or repair if necessary.
5. Checking the Transmission Control Module (TCM): Check the operation of the transmission control module, as problems with the TCM can cause the P0985 code. This may require specialized equipment and knowledge.
6. Checking the mechanical parts of the transmission: Check the mechanical components of the transmission, such as the torque converter, to rule out mechanical problems.

If you are not confident in your skills or do not have the necessary equipment, it is recommended that you contact a professional auto repair shop. Specialists will be able to conduct more detailed diagnostics and offer an effective solution to the problem.

Diagnostic errors

When diagnosing the P0985 trouble code, certain common errors or problems may occur. Here are a few of them:

1. Skipping transmission oil check: Sometimes technicians may neglect to check the transmission oil level and pressure. Low oil pressure may be a factor causing the P0985 code. Therefore, it is important to include this aspect in the diagnosis.
2. Insufficient checking of wiring and connections: Wiring problems such as breaks, shorts, or damaged wires can result in a P0985 code. It is important to thoroughly check the wiring and connections.
3. Skipping Valve Resistance Test: The oil pressure control solenoid valve has a certain resistance and its values ​​must be within the manufacturer's specifications. Failure to check this parameter properly may result in a fault being missed.
4. Ignoring other fault codes: Sometimes problems in a car system can cause multiple fault codes. It is necessary to conduct a full diagnosis and take into account all identified codes in order to exclude possible relationships between them.
5. Failure to consider transmission mechanical problems: Problems with mechanical components in the transmission, such as the torque converter or clutch, can also cause P0985. It is important to include a mechanical inspection as part of your overall diagnostics.

To avoid these mistakes, it is important to follow the manufacturer's recommendations and use the correct diagnostic methods. If necessary, it is best to contact a professional car service with experienced technicians.

How serious is the fault code? P0985?

Trouble code P0985 indicates a problem with the transmission's torque converter oil pressure control solenoid valve. The severity of this fault can vary depending on the specific situation, but in general it refers to important components of the operation of the vehicle's transmission.

Incorrect operation or failure of the solenoid valve can lead to various problems such as delayed shifting, jerking, limp mode, and increased wear on other transmission components due to improper oil pressure management.

It is important to take this code seriously and promptly diagnose and troubleshoot the problem. Leaving the problem unattended can result in more serious damage to the transmission, which will lead to more complex and expensive repairs.

If your Check Engine Light comes on with a P0985 code, it is recommended that you contact a qualified technician or auto repair shop for detailed diagnostics and repairs.

What repair will help eliminate the code? P0985?

Resolving trouble code P0985 may involve several repair steps, depending on the identified causes of the problem. Here are some possible steps:

1. Replacing the oil pressure control solenoid valve (EPC solenoid): If the solenoid valve is faulty, it may need to be replaced. This usually involves removing the old valve and installing a new one.
2. Checking and repairing wiring and connections: Carry out a thorough inspection of electrical wiring and connections. If wiring damage, corrosion or breaks are found, they should be repaired or replaced.
3. Checking and repairing transmission oil pressure: If the problems are related to the transmission oil pressure, the oil level may need to be checked and adjusted and any leaks repaired.
4. Transmission Control Module (TCM) Replacement or Repair: If the problem is with the transmission control module, it may need to be replaced or repaired.
5. Additional diagnostics of mechanical components: Performing additional diagnostics on mechanical parts of the transmission, such as the torque converter, to ensure there are no mechanical problems.

It is important to note that to accurately determine the cause and correct repair, it is recommended to contact a professional car service. Specialists will be able to conduct more detailed diagnostics, use specialized equipment and offer an effective solution to the problem.

What is P0985 Engine Code [Quick Guide]