P0985 — Shift Solenoid “E” Control Circuit Low #

Note: The fault code label may differ depending on the vehicle manufacturer.

• Ford: Shift Solenoid “E” Control Circuit Low
• GM: Shift Solenoid “E” Electrical Circuit Low Voltage
• Chrysler: Shift Solenoid “E” Control Circuit Low Input
• Toyota: Shift Solenoid “E” Control Circuit Low

Summary of Code P0985 #

The P0985 diagnostic trouble code (DTC) points to a problem with the electrical circuit controlling shift solenoid “E” in your vehicle’s automatic transmission. This solenoid is an electromechanical valve, responsible for directing hydraulic fluid to engage specific gears during shifting. When the control circuit voltage drops lower than expected, the powertrain control module (PCM)—the vehicle’s main computer—triggers this code. In simpler terms, the PCM has detected an electrical issue making it difficult or impossible for the solenoid to operate correctly, potentially affecting shift quality. The exact function and location of shift solenoid “E” can vary by transmission model, but it always plays a direct role in gear changes.

Frequent Symptoms for Code P0985 #

A vehicle with a P0985 code may exhibit a range of symptoms, from subtle to severe, depending on the extent of the electrical fault. Many drivers notice changes in how their transmission behaves, while others may only see a warning light on their dashboard. Here are the most common indicators:

• Check Engine Light illuminated on the dashboard
• Harsh or delayed gear shifts
• Transmission stuck in a single gear (commonly limp mode)
• Reduced fuel efficiency
• Slipping or erratic transmission behavior
• Possible failure to engage Drive or Reverse

Probable Causes for Code P0985 #

The P0985 code is most often rooted in electrical issues, but mechanical failures can also be at fault. The troubles can range from minor wiring concerns to internal transmission problems. Based on frequency, here are the most likely culprits:

1. Faulty shift solenoid “E” (internal electrical failure)
2. Damaged or corroded wiring/connectors in the solenoid circuit
3. Low transmission fluid or dirty fluid causing internal electrical shorting
4. Failed PCM (Powertrain Control Module) (rare)
5. Internal transmission harness problems

Step-by-Step Diagnostic for P0985 #

A systematic approach is key to pinpointing the exact cause behind code P0985. Here’s a step-by-step guide that even a DIYer with some basic tools can follow, though some steps may require a professional’s expertise:

1. Verify the code: Use an OBD-II scanner to confirm P0985 is present. Clear the code and see if it returns after a short drive.
2. Inspect transmission fluid: Check the fluid level and condition. Low or dirty fluid can cause solenoid malfunctions.
3. Visual inspection: Look for damaged wires, corrosion, or loose connectors at the transmission harness and solenoid “E”.
4. Test solenoid “E”: Using a digital multimeter, measure resistance at the solenoid’s terminals. Compare to OEM specifications—out-of-range values indicate a faulty solenoid.
5. Check circuit voltage: With the key on, check for proper voltage at the solenoid connector. Low or absent voltage may point to a wiring or PCM issue.
6. PCM check: If all wiring and the solenoid test good, consider PCM testing or reprogramming as a last resort.

Possible Repairs for P0985 #

Repairs for P0985 will depend on the root cause found during diagnosis. Addressing the underlying issue is critical to avoid further transmission damage:

• Replace the shift solenoid “E” if it fails resistance or activation tests.
• Repair or replace damaged wiring/connectors in the solenoid circuit.
• Flush and refill transmission fluid if fluid is low or contaminated.
• Replace or repair the transmission internal harness if found faulty.
• PCM repair or reflash (rare)—only after all other causes are ruled out.

Is It Safe to Drive with Code P0985? #

Driving is limited and not recommended. While some vehicles may continue to operate with only mild symptoms, others can experience significant transmission issues, such as being stuck in limp mode or severe shifting problems. Continued driving risks further internal damage and can leave you stranded. It’s best to address the fault as soon as possible and avoid extended use of the vehicle until repairs are completed.

Vehicles Most Commonly Affected by P0985 #

While P0985 is a generic OBD-II code, it appears more frequently on certain makes and models known for issues with shift solenoid circuits. The following vehicles are commonly associated with this code:

• Ford F-Series trucks (especially 2005–2015)
• Chevrolet Silverado and GMC Sierra (2007–2016)
• Chrysler and Dodge minivans (2010–2018)
• Toyota Camry and Corolla (2008–2017)
• Nissan Altima and Maxima (2012–2019)

Common Mistakes & Best Practices for P0985 #

Misdiagnosis of P0985 can lead to unnecessary parts replacement or unresolved issues. Following best practices helps avoid wasted time and money:

• Assuming the solenoid is bad without checking wiring first. Many faults are due to corroded connectors or chafed wires.
• Ignoring fluid condition. Dirty or low fluid is a frequent culprit and easy to overlook.
• Not using OEM diagnostic procedures. Always consult the manufacturer’s service manual for test specifications.
• Clearing codes without proper repair. The code will return if the root cause isn’t addressed.

Quick FAQ for P0985 #

Q: Is replacing the shift solenoid “E” difficult?
A: Access and replacement difficulty varies by vehicle. Some transmissions require pan removal, while others need partial disassembly. Always reference your OEM repair manual for guidance.

Q: Can low battery voltage trigger P0985?
A: Rarely. While low voltage can cause electrical anomalies, P0985 is typically specific to a fault in the shift solenoid circuit itself.