P077BOutput Shaft Speed Sensor Circuit - Direction Error
The TCM reads a direction from the output shaft speed sensor that contradicts the commanded gear — for example reverse direction while drive is engaged, or forward direction while reverse is engaged. Either the sensor wiring is swapped, the sensor is wrong, or the gear actually engaged is not the one commanded.
Can I keep driving? With caution
You can drive to the shop, but do not postpone the repair. The problem may worsen and damage other components.
Sistema Afectado
Transmisión · Caja y solenoides
La avería está en la transmisión: solenoides, sensores de velocidad o presión de aceite.
Espacio para vendedores de repuestos
Aún no hay un anunciante en este espacio.
Symptoms You Will Notice
What you may observe when this code appears
- 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
Possible Causes
The components or conditions that trigger this code
- 1Sensor wiring swapped after service Wrong sensor part installed
How to Fix It — Step by Step
Recommended diagnostic and repair procedure
- 1Difficulty: medium. Estimated time: 0.6-3 hours. Estimated cost: €200-€
- 2Professional repair recommended
Note: This information is for general reference. For precise diagnostics and safety repairs, always consult a certified mechanic.
Estimated Cost
Approximate range in USD (varies by region and shop)
Solenoids + transmission
* Diagnosis only: $50–$150
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