Results 1 to 3 of 3

Thread: Electrical communication failure

  1. #1
    Join Date
    Feb 2019
    Location
    Cape Town, South Africa
    Posts
    2

    Default Electrical communication failure

    Hi

    I have been all over the various forums and donít seem to have come across this issue posted for my particular model. It is a XC70 D5 2009 Tiptronic Auto model. I was driving along and suddenly heard a single knock coming from around the passenger footwell area. The car then lost a bit of power and the ABS and skid control indicator lights came on as well as the red warning triangle and a message stating: Brake Failure Stop Safely.

    After coming to a stop I put into Park and tried to switch off the engine. At first it wouldnít switch off but after pressing the button a few times it switched off but wouldnít release the key. I tried restarting but no joy.

    After organizing a tow truck to my local Volvo mechanic, he at first thought it must be the battery or alternator but none of these showed any issues. Unfortunately his diagnostic equipment couldnít pick up any communication with the onboard computers. So he sent it next door to an auto electrician who has not had any luck either. He reckons it is likely a loose power cable as it canít be that 3 of the ECUís/Comms modules could be broken at once. He has had the car for over a week but is now giving up and suggesting I get it to a proper Volvo dealership whose diagnostic equipment might be able to be better at figuring out the problem. Unfortunately my local Volvo dealership is booked up for the next three weeks, but if I have the car towed there they will see what they can do in terms of squeezing in a diagnostic check.

    The only thing that recently happened to me was that my car was mistakenly filled with petrol about 2 weeks prior to this event. But the engine hadnít been started then as I caught it while it was being filled and it was towed away, drained and flushed and all the filters replaced. So donít think it could be related.

    I see that a similar warning and issue occurs on the P2 model but as far as I can see not on the P3 models. Has anyone come across this issue before on this particular model?

    Thanks

  2. #2
    Join Date
    Feb 2019
    Location
    Cape Town, South Africa
    Posts
    2

    Default Solution

    I thought to let anybody who has a similar problem in future know that I eventually found the solution to my problem. After sitting without my car for a month, the dealer eventually traced the fault to the wiring to the rear differential control module that had been pushed up against the exhaust and had melted and shorted this wiring. Apart from the issues experienced below, the technicians found that the network on the car was sitting at 12V and not 2V and that it was therefore likely to be a short somewhere. Big relief when it was eventually sorted with a very simple solution.

  3. #3
    Join Date
    Aug 2017
    Location
    Pleasanton CA USA
    Posts
    255

    Default

    Thanks for the epilog. Problem resolutions are the real gems of these postings.

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •