Technical Description of OBD-II Trouble Code
Electrical Issue with Shift Solenoid D
What does that signify?
This is a standard diagnostic trouble code (DTC) for transmission and is usually found in OBD-II vehicles with automatic transmissions.
This can apply to various vehicles including Chrysler, Ford, Dodge, Hyundai, Kia, Ram, Lexus, Toyota, Mazda, Honda, VW, etc. Although it is a generic code, the specific repair steps may vary depending on the year, make, model, and powertrain configuration.
Most automatic transmissions have multiple shift solenoids, depending on the number of gears. The trouble codes associated with the “D” solenoid are P0765, P0766, P0767, P0768, and P0769, depending on the specific malfunction that triggers the PCM to set the code and illuminate the Check Engine Light. If your vehicle has an Overdrive or other transmission warning lamp, it may also be illuminated.
The purpose of the Shift Solenoid Circuit is for the PCM to monitor the shift solenoids, manage the fluid movement between hydraulic circuits, and change the transmission gear ratio at the appropriate time. This process optimizes engine performance at the lowest RPM possible.
Automatic transmissions rely on bands and clutches to change gears, which is achieved by maintaining fluid pressure in the right place at the right time. The transmission solenoids are responsible for opening or closing valves in the valve body to allow transmission fluid to flow to the clutches and bands, enabling smooth shifting as the engine accelerates.
When the Powertrain Control Module (PCM) detects a malfunction in the Shift Solenoid “D” Shift Circuit, various codes can be triggered depending on the specific vehicle, transmission, and number of gears in the automatic transmission. In this case, the P0768 OBD-II trouble code is associated with an electrical malfunction in the transmission Shift Solenoid “D” Circuit.
Example of shift solenoids:
What is the severity of this DTC?
Initially, the severity of this code is moderate, but if not corrected promptly, it can escalate to a more severe level.
What are some of the symptoms of the code?
Symptoms of a P0768 trouble code may include:
What are some of the common causes of the code?
Possible causes for this P0768 transmission code may include:
What are some P0768 troubleshooting steps?
Prior to starting the troubleshooting process for any malfunction, it is recommended to research the Technical Service Bulletins (TSB’s) specific to the vehicle’s year, model, and transmission. This can save time by providing guidance in the right direction. It is also advisable to check the vehicle records to determine the last time the filter and fluid were changed, if possible.
Fluid & Wiring Inspections
The first step is to ensure that the fluid level is correct and inspect the fluid for contamination. Then, perform a thorough visual inspection of the associated wiring for any obvious defects such as scraping, rubbing, bare wires, or burn spots.
Next, check the connectors and connections for security, corrosion, and damaged pins. This includes all wiring and connectors to the transmission solenoids, transmission pump, and the PCM. Additionally, inspect the transmission linkage for security and any binding issues based on the configuration.
Advanced Steps
The advanced steps are highly vehicle-specific and require the appropriate advanced equipment for accurate performance. These procedures involve using a digital multimeter and referencing the specific technical data for the vehicle. Voltage requirements will vary based on the vehicle’s specific year and model. It is important to follow the specific troubleshooting chart for the vehicle.
Continuity Checks
Continuity checks should always be performed with the power removed from the circuit. The normal readings for wiring and connections should be 0 ohms of resistance, unless otherwise specified by the technical data. Resistance or lack of continuity indicates faulty wiring that is open or shorted and must be repaired or replaced.
What are some common repairs for this code?
We hope that the information provided in this article has been helpful in addressing the issue with your Shift Solenoid Circuit fault code. However, please note that this article is strictly informational and the specific technical data and service bulletins for your vehicle should always take priority.
