speedytt

Ok, folks. I've been off this list for a while, but now i'm back with a technical question. 1 year ago I replaced my gauge face with a cream one from the TT Shop. Everything had been fine until 1 week ago. Somehow, when the car is stone cold, you turn the key on and the coolant gauge reads high. Off the rest position 1 mark or 16C degrees positive. When the car is up to temperature, the car temp is close(ish) to redline. I've been driving like this for 1 week. Yesterday at work, I get in the car for lunch and when I turn the key on, the fault display has a water symbol on it with the word SENSOR underneath. I called the dealer who had me bring it in the next day. The dealer said that I need to replace the gauge cluster. They ran a 1550 (?) and had no fault codes displayed. The svc manager was very cool about the gauge face, but said that when the new one comes in, they would have to set it up for the car and have me pull the needles and do the swap, then they would put it in the car for me. Guess I was lucky there. Because of the fault symbol with the word SENSOR on it, I think they are wrong. I'm thinking it's the sending unit. The svc manager is going to call their rep for advice on the fault.

Anyone have any thoughts?

PlainRuss

Well, not that Audi's aren't known for coolant temp sensors going bad, but typically when they do they will throw a fault code. It is very possible it's in the cluster. I have seen the TT clusters do all sorts of crazy things and that really wouldn't surprise me. Really though using the scan tool it would be easy to figure out. They could just look at the measuring value blocks and see what the cluster is getting fed to it. Can also look at it in the ECM as well. Cool though they are going to let you swap your needles over and what not. Good luck.

speedytt

I found the instructions online for checking engine diagnostics using the climate control. A check of codes gave me a reading of 65C and looking at the cluster gauge, it's about 87C. I would imagine that there is only one coolant temperature sending unit on the car...

-Brad

TTschwing

Is the coolant temp sensor. These are known failure points. The green one is the improved version on the 225 and only about $5. On the display info, it is also common for the sensor leads to get corroded in the overflow tank and give a false reading when the fluid is not really low. These metal leads can be cleaned, but the entire tank with new leads is not very expensive. If all that fails, replug your connectors on the back of the cluster. It could be a bad cluster, but I'm betting on one of the others.......

mcgilla

...3 minute repair with a regular screwdriver to pull the clip ring...make sure you hold onto the ring as it's removed...oh..this sensor is on the hose assembly..below/near the intake hose to the turbo...also a small bit of Si grease would'nt hurt on the o-ring...but if you don't have Si grease...do not use anything else..<ul><li><a href="http://www.ecstuning.com/stage/edpd/pagebuild_v2.cgi/?partnumber=078919501CKIT&amp;html=learnmore.html" >http://www.ecstuning.com/stage/edpd/pagebuild_v2.cgi/?partnumber=078919501CKIT&amp;html=learnmore.html</a</li></ul>

TTahoe

If you have an early FWD you may need the blue A4 one. (about $16.00)

mcgilla

thanks...that's because it's a different connector...