IGA Logo Helpdesk
Home Recent Topics Recent Posts Search FAQ

IGA Members Forum



Register | Lost password  
Messages in this topic - RSS

Home » Transmission - Clutch, Gearbox and final drive » Audi A6 - 7 Speed Multitronic Gearbox Fault

24/02/2015

FRC
FRC
Posts: 5
Good day to you,
One of our customers has been experiencing a drivability problem with their 2006 Audi A6 Auto and I was wondering if you would be so kind as to cast your eye over the details and let us know your thoughts please?


Vehicle Details;
  • Audi A6 S-Line
  • 2006
  • Auto (7 speed multitronic)
  • 2.0 TD
  • Engine Code – BRE
  • Chassis No. - WAUZZZ4F86N144923
  • Mileage – 66995

The Symptoms;
After approximately 30 minutes of normal driving the following series of events occur;

  • Vehicle starts to judder briefly (this occurs 2-3 times, approx. 1000 yards apart between each judder and then stops occurring).
  • After approx. another 1000 yards the ESP warning lamp illuminates continuously but with no driving faults.
  • After approx. ¼ mile the ‘Parking brake malfunction’ message (along with the already illuminated ESP lamp) appears in the instrument cluster display, the gear selector indicator display disappears from the instrument cluster and the vehicle then loses drive (the engine can be revved up with no response from the gearbox and the vehicle loses road speed, down to as little as 2mph).
  • Vehicle drive and gear selector indicator display return simultaneously but the other warning lamps/messages remain illuminated. *
  • * This last event can reoccur several times and each time drive comes back so does the gear selector display, when drive is lost so is the gear selector indicator display!

The Codes;
(These codes were retrieved using VCDS and the vehicle’s system was clear of codes prior to the above events)
  • 02083 – message for delay request 004 no signal/comms. (from ENGINE)
  • 01315 – transmission control module 004 no signal/comms. (from ENGINE)
  • 01119 – gear recognition signal 000. (from ABS)
  • 18289 – powertrain databus missing message acceleration request. (from AUTO BOX – P1881)
  • 006215 – check DTC memory of ABS controller. (from ABS – P1847)
  • 005670 – powertrain databus, missing message from TCU. (from ABS – P1626)
  • 0053250 – check fault codes in comfort control (J393). (from AUTO BOX – U1002)

Our Conclusion;
The conclusion we drew from the above symptoms and codes, was that the Transmission Control Unit (TCU) had a temperature related internal fault, which in-turn was causing a communication fault on the network. As a result we removed the unit and sent it to ECU Testing for a bench test. Initially they found no fault and attempted to return the unit to us. We re-explained that the fault occurred after approx. 30 minutes of driving and requested they carry out an extended test, which they did but this further testing still showed the unit to be fault free! The unit was subsequently returned to us and is still out of the vehicle.

Questions;
As far as we can tell from the vehicle history, the auto gear box has not yet had an oil replacement (this will obviously be carried out when the module is re-fitted!).
Could the lack of fresh oil possibly cause other internal gearbox components to fail and simulate TCU failure?

The other information we do not have at this stage, is at which point the codes occurred and in which order - relative to the symptoms.
Do you think it be worth re-fitting the module, with fresh oil to enable this information to be gathered?

From the information above, do you have any other suspicions as to the cause of communication failure?



If you could let us know what you think of our findings, we would be very grateful of your input.
0 link
24/02/2015


Guest
Wiring guide attached, may be worth checking the CAN lines out, there is a connector in the plenum chamber which may be susceptible to water damage particularly if the drain points are blocked in the valley area.

Hope this helps
0 link

Home » Transmission - Clutch, Gearbox and final drive » Audi A6 - 7 Speed Multitronic Gearbox Fault