P0785 - SHIFT/TIMING SOLENOID "A" MALFUNCTION

The shift/timing solenoids allow the automatic transmission to achieve seamless shifting according to driving needs. The Transmission Control Module (TCM) is responsible for monitoring and controlling the operation of these solenoids.

The purpose of the shift/timing solenoids is to help the transmission shift properly. The system is usually equipped with a variety of solenoids, which is why you should consult your vehicle’s information source to identify the “A” shift/timing solenoid in your vehicle.

When the DTC P0785 OBDII code is stored, it is because the Engine Control Module (ECM) found a general malfunction of the shift/time “A” solenoid circuit. This malfunction can be caused by electrical or mechanical problems.

• Check Engine light illuminated.
• Transmission shifts erratically.
• Transmission slipping.
• Problems during acceleration.
• Reduced overall vehicle performance.

The reasons for the P0785 OBD2 trouble code being set are:

• Possibly the shift/timing solenoid is faulty.
• Perhaps the transmission fluid is dirty or has an excessively low level.
• There could be obstructions in the transmission fluid passages.
• System wiring or connectors may be defective.

To troubleshoot the P0785 OBDII diagnostic code you should do the following:

• Consult the TSB (Technical Service Bulletins), provided by the manufacturer of your vehicle.
• Check if the transmission fluid is dirty or has an abnormal color. If so, it should be replaced.
• Check the shift/timing solenoid, in case it is not internal, along with its cables and respective connectors. Look for any defects in these components. Repair or replace it as necessary.
• With a multimeter test the resistance between the solenoid pins. The readings you obtain should be within the parameters indicated by the manufacturer. If not, replace the solenoid.