The relationship between reported engine and transmission speeds depends on the gearbox design and operating state. A difference is not automatically proof of slipping or a defective speed sensor.
Keep the relevant state
Record selected gear, load, temperature and the exact parameter labels. The technician should identify which shaft each value represents and what comparison the manufacturer expects. A screenshot at an unknown moment cannot establish a ratio fault.
If the complaint involves slipping or lost drive, include that separately with the full scan. Ask the workshop to explain how measured behaviour supports its conclusion rather than judging two numbers by whether they happen to match while the vehicle is stationary.
Need help with this fault?
- Gearbox Adaptation Values Need the Correct Units and Limits
- Transmission Pressure Requested and Actual Values Diverge
Browse this collection or prepare a vehicle and module enquiry. Tell us about the vehicle, the fault and any tests already done. Contact our Didcot workshop before travelling or posting a module. Visits are by appointment.