What it means
The transmission control module monitors the output shaft speed sensor circuit and checks whether its direction signal is plausible. It sets this code when the reported direction is inconsistent with expected transmission operation.
At a glance
- Usually lights the check-engine light
How it works
The output shaft speed sensor reports shaft speed and direction to the TCM, which checks whether that direction makes sense for the selected gear and vehicle operation. This code sets when the reported direction is implausible, including after sensor wiring has been reversed or an incorrect sensor has been installed.
Common causes
Most likely first.
- Sensor wiring swapped after service
- Wrong sensor part installed
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- Review freeze-frame data and transmission codes to identify the selected gear and direction signal when the TCM detected the mismatch.
- Check live output shaft speed and direction data while safely selecting forward and reverse, if the scan tool displays direction.
- Inspect the sensor connector and harness for crossed or repaired wires, loose terminals, and damage from recent transmission work.
- Verify that the installed output shaft speed sensor is the correct type for the vehicle using the manufacturer's parts and service information.
- Test sensor wiring polarity and continuity against the vehicle wiring diagram, then confirm the sensor signal follows actual shaft direction.
- If the sensor and wiring are correct, inspect the sensor target and TCM input using the manufacturer's procedure.
Common fixes
- Correct crossed or misrouted sensor wires following the vehicle wiring diagram.
- Install the correct output shaft speed sensor if the wrong type was fitted.
- Repair damaged terminals or harness sections at the sensor connector.
- Repair a damaged sensor target or TCM input only if testing confirms the fault.
Can I keep driving?
Avoid driving at speed if the transmission shifts unpredictably or the direction reading is inconsistent, and do not rely on reverse or gear selection until operation is verified. Incorrect direction information can disrupt shift control and may lead to further transmission stress.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.