P0768
Shift Solenoid D Electrical.
- Generic
- Powertrain
- Generic code
- Medium severity
How this code is built
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- 7
- AreaTransmission
- 68
- FaultThe specific fault in that area
What it means
P0768 is the generic code for an electrical fault in the shift solenoid D circuit. The transmission control module has seen a voltage or current in the circuit that does not match what it commanded, such as an open circuit, a short to earth or a short to voltage. Which gear or function solenoid D controls depends on the make, model and gearbox, so check the manufacturer data.
Symptoms
- Warning light on (check engine and sometimes a transmission warning)
- Gearbox stuck in one gear (limp mode), often third or fourth
- Harsh, delayed or flared gear changes
- Missing or incorrect gear selection, or no upshift or downshift
- Poor fuel economy or reduced performance
- Torque converter lock-up not working on some gearboxes
Possible causes
- Damaged, chafed or corroded wiring between the transmission control module and the solenoidlikely
- Poor connection at the gearbox internal harness connector or the control module plug, including corrosion or water ingresslikely
- Faulty shift solenoid D with an open or shorted windinglikely
- Damaged internal gearbox wiring loom, or valve body/mechatronic unit faultpossible
- Contaminated or degraded transmission fluid affecting the solenoidpossible
- Low or unstable battery or charging voltagepossible
- Faulty transmission control module driver circuitrare
How to diagnose
- Read all stored codes and freeze frame data to see when the fault set and whether other transmission or voltage codes are present
- Check the battery condition and charging voltage, as low voltage can cause false electrical faults
- Inspect the external wiring and connectors to the gearbox for chafing, heat damage, corrosion, fluid contamination and pushed-out pins
- Check the transmission fluid level and condition against the manufacturer's procedure, and note any metal debris or burnt smell
- Measure the solenoid D resistance at the connector and compare it with the manufacturer's specification
- Check the supply, earth and signal wiring to the solenoid for continuity and shorts, using the wiring diagram for the model
- Use a scan tool to command the solenoid on and off, where supported, and watch for a response
- Check for technical service bulletins or software updates for the gearbox for this model
How to fix
- Repair or replace damaged wiring and clean or replace corroded or damaged connectors
- Replace the faulty shift solenoid D, or the solenoid pack or valve body where it is not supplied separately
- Replace the internal wiring harness or connector seal if it is damaged or leaking
- Change the transmission fluid and filter with the correct specification where it is contaminated or degraded
- Repair the battery or charging system fault if voltage is out of range
- Repair or replace the transmission control module only after wiring and solenoid have been proven good, and apply any manufacturer calibration update that applies to the fault
Can I keep driving?
Medium severity
The car can usually be driven carefully for a short time, but the gearbox may be in limp mode with limited gears. Have it checked soon, because driving on can cause further wear or damage to the gearbox.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.