Audi A2 Radiator Fan Failure Causing Engine Overheat

Had the same temperature control issues with my Audi A4 (2006, 1.8T). The engine cooling problems started similarly, overheating at low speeds with check engine light activation. The thermal switch was failing to properly activate the radiator fan, causing inconsistent engine cooling. Initial diagnosis showed the fan working intermittently, but the root cause was more complex. The entire cooling system needed inspection. The repair required: Testing the radiator fan operation, Replacing the thermal switch, Checking coolant levels and circulation, Verifying the temperature sensor functionality This was a serious issue requiring immediate attention since continuous overheating risks severe engine damage. The repair process took about 4 hours at the shop. Before replacement, you can test if the fan activates when starting the engine from cold. The radiator fan should turn on when the engine reaches operating temperature. If it fails this basic test, the thermal switch or fan motor likely needs replacement. Consider checking the coolant level and looking for any visible leaks around the radiator first. These simple checks might reveal obvious issues before visiting a mechanic.

Thanks for sharing your experience. My overheating problem turned out quite similar, and replacing the fan motor along with the thermal switch resolved the car overheating issues. The fan blade was also slightly damaged, which explained the strange noise I initially ignored. Curious about your repair costs, would you mind sharing what you paid? Mine was fixed about 6 months ago and cost roughly 450 Euro for parts and labor. The cooling system now works perfectly, but I noticed the coolant needed a top-up recently. Have you experienced any additional problems since the repair?

Glad to hear you got the radiator fan fixed. After my repair experience last year, I also had complete resolution of the engine cooling problems. The total cost was 250 Euro for replacing the speed sensor, which was much more reasonable than your repair since fortunately my fan blade was intact. The cooling system has worked flawlessly since the fix. Regarding your coolant top-up concern, a minor coolant loss over 6 months is fairly normal due to the temperature control cycles. However, if you notice frequent need for top-ups, having the system pressure tested might be worthwhile to check for small leaks. My car has maintained proper temperature control with no fan noise issues since the repair. Just keep monitoring your coolant levels every few months as part of regular maintenance to ensure optimal engine cooling performance.

Thanks for the input. I finally got my car fixed last week and wanted to share how it went. Found a well-rated independent shop that specializes in European cars. The mechanic immediately identified the radiator fan issue and showed me how the fan motor was failing. The repair included replacing both the fan motor and damaged fan blade. Total cost came to 450 Euro including parts and labor. The fan noise completely disappeared and the engine temperature now stays perfectly steady, even in slow traffic. The mechanic also checked the entire cooling system and topped up the coolant. Much better experience than my previous shop, they explained everything clearly and completed the work in one day. The car radiator is working great now and no more check engine lights. Going to stick with this shop for future repairs. Sometimes paying a bit more for quality work saves money in the long run.