VW Suran Transmission Failure with Warning Light Alert

Had similar symptoms with a 2013 VW Golf TSI. Initially thought it was just a transmission issue, but diagnostic tests revealed multiple connected problems. The main culprit was a faulty oil cooler causing cross-contamination between transmission fluid and radiator coolant. When coolant mixes with transmission fluid, it creates those grinding sounds and erratic shifting patterns you described. The pressure sensor was also giving false readings because of this contamination. The repair required: Complete flush of transmission fluid and radiator coolant, Replacement of the oil cooler unit, New pressure sensor installation, Thorough leak detection throughout the cooling system The emergency mode activation was actually protecting your transmission from further damage. This was definitely a serious issue that needed immediate attention. If left unfixed, it could have led to complete transmission failure. The symptoms match your case very closely, and the mechanic pointing to coolant and sensor issues is on the right track. Would suggest getting the oil cooler checked as part of the diagnosis.

Thanks for sharing that insight about the oil cooler and coolant leak issues. My case seems identical. Finally got it fixed last week and the transmission is shifting smoothly again. Quick question, do you remember roughly what you paid for the complete repair? Also, has your transmission been working properly since the fix, or have you noticed any other problems? Currently monitoring mine closely for any signs of car overheating or cooling fan issues.

Good to hear your transmission is working properly again. After fixing the radiator oil pressure sensor connection, which only cost 95€ for a new cable harness and labor, my transmission has performed flawlessly for over a year now. The cooling fan and transmission operate normally with no overheating issues. This was much cheaper than my initial repair which needed the full system overhaul I described earlier. Sounds like you caught the problem early since only the sensor connection needed repair. Regular coolant level checks and monitoring the cooling system performance are still good practice though. A properly functioning pressure sensor is crucial for preventing any future transmission damage or oil cooler problems. Keep an eye on the transmission fluid color during your next service, it should be clear red without any signs of coolant contamination. This will confirm the repair fully resolved the issue.

Wanted to update everyone on the final outcome. Took the car to a transmission specialist who immediately spotted the coolant leak near the oil cooler. The entire repair ended up costing 850€, including: The mechanic found cross-contamination between the transmission fluid and cooling system, exactly as described. They flushed both systems, replaced the faulty oil cooler, and installed a new pressure sensor. The grinding noise completely disappeared after the repair. Been driving for about a week now and the transmission shifts perfectly. No warning lights, no rough shifting, and the cooling system maintains proper pressure. Really glad I got a second opinion and found the actual root cause instead of just replacing parts out of nowhere. For anyone else seeing these symptoms, definitely check the connection between your transmission cooling and radiator coolant systems. The pressure gauge readings can help diagnose if you have similar cross-contamination issues.