P0968 Code: Complete DIY Repair Guide

The P0968 trouble code is a diagnostic trouble code (DTC) that indicates a problem with the Pressure Control Solenoid “C” control circuit in vehicles equipped with automatic transmissions. This code is set when the Powertrain Control Module (PCM) detects an open circuit in the solenoid, which is responsible for regulating the hydraulic pressure necessary for smooth gear shifts. Understanding this code is crucial for vehicle owners and DIY mechanics, as it can lead to significant transmission issues if not addressed promptly.

Symptoms of P0968 Trouble Code

When the P0968 code is triggered, several symptoms may manifest, indicating potential transmission problems:

• Check Engine Light: The most immediate sign is the illumination of the Check Engine Light on the dashboard.
• Transmission Slipping: Drivers may experience slipping during gear changes, which can feel like a delay or a sudden loss of power.
• Harsh Shifting: The vehicle may exhibit hard shifting, where gears engage abruptly rather than smoothly.
• Increased Fuel Consumption: A malfunctioning transmission can lead to inefficient fuel use, resulting in higher gas expenses.
• Overheating Transmission: The transmission may overheat due to improper fluid pressure regulation.
• Limp Mode Activation: In severe cases, the vehicle may enter limp mode, limiting speed and power to prevent further damage.

Technical Explanation of P0968

The P0968 code relates specifically to the Pressure Control Solenoid “C,” which plays a vital role in controlling hydraulic pressure within the automatic transmission. The solenoid adjusts fluid flow based on signals from the PCM, ensuring that the correct pressure is applied for smooth gear shifts. When this circuit is open, it means that there is a break in the electrical connection, preventing the solenoid from functioning correctly.

This issue can arise from various factors, including damaged wiring, corroded connectors, or a faulty solenoid itself. If left unaddressed, these problems can escalate to more severe transmission failures or even complete transmission failure.

Step-by-Step Diagnosis of P0968

Diagnosing the P0968 trouble code involves several systematic steps:

1. Initial Inspection:

• Check for any other DTCs that may provide additional context.
• Inspect the vehicle’s service history for any recent repairs or fluid changes.

1. Fluid Condition Check:

• Examine the transmission fluid level and condition. Look for signs of contamination or burnt fluid.
• If necessary, replace the fluid and filter before proceeding with further diagnostics.

1. Wiring and Connector Inspection:

• Conduct a visual inspection of all wiring and connectors related to the pressure control solenoid.
• Look for frayed wires, loose connections, or signs of corrosion.

1. Solenoid Testing:

• Using a multimeter, check the resistance of the pressure control solenoid. Compare readings against manufacturer specifications.
• If readings are outside of specifications, consider replacing the solenoid.

1. PCM and TCM Evaluation:

• If no issues are found with the solenoid or wiring, test the PCM and Transmission Control Module (TCM) for faults.
• Reprogramming or replacing these components may be necessary if they are found to be defective.

Solution Methods for P0968

To resolve issues related to the P0968 trouble code, consider these common repair methods:

• Replace Faulty Pressure Control Solenoid: If testing indicates a malfunctioning solenoid, replace it with a new one.
• Change Transmission Fluid and Filter: Regular maintenance can prevent many issues; ensure that both fluid and filter are clean and functioning properly.
• Repair Damaged Wiring/Connectors: Fix any identified wiring issues or replace corroded connectors to restore proper electrical flow.
• Inspect and Repair Transmission Pump: If there are signs of pump failure, repair or replace it as necessary.
• Check Valve Body Functionality: A malfunctioning valve body can also cause similar symptoms; inspect and repair as needed.
• Reprogram or Replace PCM/TCM: If all other components are functioning correctly but problems persist, consider reprogramming or replacing these modules.

Cost Estimates

The cost of repairs related to P0968 can vary significantly based on labor rates and parts prices:

• Pressure Control Solenoid Replacement: $100 – $300 (parts and labor)
• Transmission Fluid Change: $100 – $200
• Wiring Repairs: $50 – $150 depending on complexity
• Transmission Pump Replacement: $300 – $800
• PCM/TCM Replacement: $400 – $1,200

These estimates can fluctuate based on vehicle make and model as well as regional labor costs.

Warnings and Recommendations

When dealing with transmission-related issues:

• Always consult your vehicle’s service manual for specific diagnostic procedures and specifications.
• If you are not comfortable performing these diagnostics or repairs yourself, seek professional assistance to avoid further damage.
• Be cautious when handling electrical components; disconnect the battery before working on wiring or connectors to prevent shorts.

Closing Paragraph

The P0968 trouble code indicates a significant issue within your vehicle’s automatic transmission system that requires prompt attention. By understanding its causes, symptoms, and solutions, vehicle owners can take proactive steps toward diagnosing and repairing their vehicles effectively. Whether you choose to tackle this issue yourself or seek professional help, addressing this code promptly can prevent more severe damage down the line and ensure your vehicle operates smoothly.

Frequently Asked Questions About P0968

• What does error code P0968 mean?
  P0968 indicates an open circuit in Pressure Control Solenoid “C,” affecting hydraulic pressure regulation in automatic transmissions.
• What are common symptoms of P0968?
  Symptoms include harsh shifting, slipping transmission, overheating, increased fuel consumption, and activation of limp mode.
• Can I drive my car with a P0968 code?
  While it may be possible temporarily, driving with this code can lead to severe transmission damage; it’s best to address it promptly.
• How do I fix error code P0968?
  Fixes include replacing faulty solenoids, changing transmission fluid/filter, repairing wiring/connectors, or addressing PCM/TCM issues.
• Is P0968 a serious code?
  P0968 can escalate into severe transmission problems if not resolved quickly; immediate attention is recommended.
• What tools do I need to diagnose P0968?
  A diagnostic scanner, multimeter for electrical testing, and basic hand tools for inspection are essential.
• How much does it cost to fix a P0968 code?
  The total cost varies widely but generally ranges from $100 to over $1,200 depending on required repairs.
• Should I seek professional help for P0968?
  If you are unsure about diagnosing or repairing yourself, consulting a professional mechanic is advisable.