Fault code P0986 – shift solenoid “E” control circuit high

Fault code P0986 is called “Shift Solenoid “E” Control Circuit High” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.

Technical description and explained code P0986

This diagnostic trouble code (DTC) is a generic transmission code. Error P0986 is considered a general code because it applies to all makes and models of vehicles. Although the specific repair steps may vary slightly depending on the model.

Fault code P0986 – shift solenoid

Fault code P0986 OBD-II is set when the control module (PCM) has detected a high signal level. A high level has been detected in the control circuit of the “E” shift solenoid valve.

The transmission shift solenoid valves are used to control fluid pressure and proper operation of the automatic transmission. The TCM receives an electronic signal based on the pressure inside the solenoid valve.

The automatic transmission is controlled by belts and clutches that shift gears by applying fluid pressure at the right place at the right time.

Based on signals from related devices that control vehicle speed, the TCM controls the solenoid valves. To direct the fluid at the proper pressure to the various hydraulic circuits. Which change the transmission ratio at the right time.

During operation, the TCM checks the operation of the solenoid valves, including resistance checks and speed sensor checks.

If one of these checks fails, such as a short circuit on the solenoid valve. The TCM disconnects this control circuit and sets the code P0986 in the control module memory.

Symptoms of vehicle malfunctions

The main signal that an error P0986 has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.

It can also be warning signs such as:

  1. The “Check engine” control lamp on the control panel will light up (the code will be recorded in the memory as a fault).
  2. The vehicle goes into emergency mode.
  3. The transmission slips when shifting gears.
  4. Transmission is stuck in gear.
  5. Shifting gears is hard.
  6. Transmission overheating.
  7. Increased fuel consumption.
  8. Possible symptoms similar to ignition failure.

The severity of fault code P0986 is usually moderate, as there should be no problems with drivability. But transmission problems can be serious if not corrected in time.

Factors that can cause this error code

The error code P0986 can mean that one or more of the following problems have occurred:

  • The shift solenoid valve is defective.
  • Contaminated fluid or clogged transmission filter.
  • Low transmission fluid level.
  • Transmission fluid passages are clogged.
  • Faulty transmission pump or transmission valve housing.
  • Other mechanical problems inside the transmission.
  • A wiring problem or damaged connector.
  • In rare cases, malfunction of PCM or TCM.

How to fix or reset OBD-2 code P0986

Some suggested steps for troubleshooting and fix the error code P0986:

  1. Change ATF fluid and filter.
  2. Fill transmission fluid to required level.
  3. Flushing to clean the internal channels of the transmission.
  4. Test, if necessary replace defective shift solenoid valve.
  5. Repair or replace faulty transmission pump and transmission valve housing.
  6. Check connectors as well as wiring.
  7. Flash or replace PCM or TCM.

Diagnose and repair of problems

Before you begin the process of troubleshooting P0986, you should research the Technical Service Bulletins (TSBs) for your specific vehicle. In some cases, this can save you a lot of time by pointing you in the right direction.

Next, you should check the fluid level and inspect it for contamination. Before changing the fluid, you should look at the vehicle’s records to see when the filter and fluid were last changed.

You should then perform a detailed visual inspection to check the condition of the wiring for obvious defects. Inspect the connectors and wiring to the shift control solenoid valve, transmission pump and PCM. Depending on the configuration, the transmission pump may be electrically or mechanically driven.

Normal readings for wiring and connections should be 0 ohms of resistance. Wiring continuity checks should always be performed with power disconnected from the circuit to avoid shorting and creating additional damage.

Resistance or lack of continuity indicates faulty wiring that is open or shorted. In this case, repair or replacement will be required to clear code P0986.

On which vehicles does this problem occur most frequently

Fault code P0986 can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:

  • Chevrolet (Captiva)
  • Ford (Kuga)
  • Honda (Accord)
  • Lexus (GX470, IS250)
  • Mazda (RX-8)
  • Opel (Antara)
  • Toyota ( Camry, Highlander, Land Cruiser, Sienna, Tacoma, Tundra)

Fault code P0986 can sometimes be found with other errors. The most common are the following: P0981, P0982, P0983, P0984, P0985.


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