Satty B
21-04-2009, 11:09 AM
Hi there, my beloved A8 has been giving me quite a headache over the past few weeks. Intermittently (now more often than not), it simply won’t start (PRDNS all show up in red) :zx11:. Have checked with VAG-COM, which consistently points to the ‘no signal/communication’ with the Transmission Control Module on a number of fronts (ie start authorisation/engine etc). If and when it does get going, it runs like a dream and all fault codes disappear . :o
I have attached the VAG-COM log for anybody who would like to/coulreview.
In the past I had thought that it was a power issue – on topping up the battery and reconnecting, the car would fire up first time, but wasn’t guarantee on how long it would last (never broke down once started, always the following day/few days later). I’ve had this checked out, and have been told the battery/alternator are fine. This may have just been a coincidence, or somehow I may have been resetting the problem? Oil and filter for the gearbox has also recently been changed (well after the problem started). Have also had the odd day where it won’t fire up in the morning, but later on in the day, it has started!!
My query is this, could this be just faulty connections with the TCU (TCM)? More importantly, where exactly on the car is the TCU located so I could check?!?! The worst case obviously is that the module may be faulty and need replacing, is this a common issue? A brand new one is in the region of £1400……..
Any help/thoughts/pointers on this would be greatly appreciated.:beerchug:
I have attached the VAG-COM log for anybody who would like to/coulreview.
In the past I had thought that it was a power issue – on topping up the battery and reconnecting, the car would fire up first time, but wasn’t guarantee on how long it would last (never broke down once started, always the following day/few days later). I’ve had this checked out, and have been told the battery/alternator are fine. This may have just been a coincidence, or somehow I may have been resetting the problem? Oil and filter for the gearbox has also recently been changed (well after the problem started). Have also had the odd day where it won’t fire up in the morning, but later on in the day, it has started!!
My query is this, could this be just faulty connections with the TCU (TCM)? More importantly, where exactly on the car is the TCU located so I could check?!?! The worst case obviously is that the module may be faulty and need replacing, is this a common issue? A brand new one is in the region of £1400……..
Any help/thoughts/pointers on this would be greatly appreciated.:beerchug: