VW Touareg No-Start: ECU Failure Warning Signs

Having moderate experience with VAG cars, I faced a similar situation with my 2006 VW Passat last winter. The symptoms were nearly identical, clicking sound, check engine light, and ECU error messages on the dash. After several failed start attempts and basic engine diagnostics showing inconclusive results, I took it to my regular workshop. Despite having a new battery, they found the cable connections were actually loose and corroded underneath where it wasnt visible at first glance. The ECU issue and engine software errors were actually false readings caused by unstable power supply. The fix involved cleaning the connections thoroughly, replacing some corroded cable ends, and properly securing all battery connections. Total cost was 155€ and the car was ready within a day. The engine light cleared itself after a few start cycles. To better assist with your Touareg issue, could you share: Have you checked the voltage at the battery terminals while attempting to start? Does the problem occur more after the car sits for several days? Are there any other electrical issues like dim lights or slow power windows? What engine variant does your Touareg have? This could help determine if youre dealing with the same underlying issue or if theres something else causing the ECU failure symptoms.

Last service was at 38000km and my Touareg has always been dealer maintained. The engine fault condition you described sounds very similar to what I experienced. However, in my case it turned out to be a failed fuel injection control module rather than battery connections. The fuel injection system wasnt receiving proper signals from the ECU, leading to both starting issues and the error messages. After thorough engine diagnostics, my mechanic found that moisture had damaged the control module connectors. The clicking sound was actually the fuel pump trying to prime but failing due to the faulty signals. The complete repair including parts and labor came to 480€ and took 2 days to complete. The engine stalling issues disappeared completely after replacing the module and clearing the ECU codes. Might be worth having your mechanic specifically check the fuel system control components rather than focusing solely on the battery connections.

Thanks for the detailed follow-up about your fuel injection control module issue. Our cases show how similar symptoms can have different root causes. In my Passat situation, while the battery connections solved the immediate problem, I actually experienced intermittent engine stalling about a month later. Further engine diagnostics revealed that my fuel injection system also needed attention, though not a complete module replacement like yours. The fuel pressure regulator was failing, causing irregular fuel delivery and triggering ECU failure warnings. The repair was cheaper at 290€ but still took 2 days due to parts availability. This explains why the check engine light occasionally returned even after fixing the battery connections. A proper fuel system inspection should definitely be on the checklist when dealing with starting problems, especially with these VAG engines where the fuel injection system is quite sensitive to electrical issues. Have you noticed any improvement in overall fuel efficiency since the repair? With my Passat, I saw about 8% better consumption after getting everything sorted properly.

Thanks for sharing those repair costs and details about the Passat issues. Your experience with both electrical and fuel system problems matches what my mechanic initially suspected with my Touareg. After the fuel injection control module replacement, fuel efficiency improved by about 10%. The engine software is now running perfectly with no more error codes or ECU issues. Its interesting how the engine stalling you experienced was connected to the fuel pressure regulator, my mechanic actually checked that component first before finding the failed control module. The biggest relief is that the repair costs stayed under 500€. I was worried it might need a complete ECU replacement which would have been much more expensive. Having the car back in 2 days was also faster than expected, especially since the engine diagnostics initially pointed to several possible problems. For anyone dealing with similar starting issues and ECU failure warnings, definitely worth having both the electrical connections and fuel injection system thoroughly checked. What seems like a simple starting problem can have multiple underlying causes.