Results 1 to 6 of 6

Thread: Fault Code B3040

  
  1. #1
    Status
    Offline
    whitegsd's Avatar
    AOC Newbie
    Join Date
    Sep 2008
    Posts
    3
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)

    Fault Code B3040

    Hi,
    I'm a new member and I have a problem with my 2001 Astra G 1.8 16v SXi engine code Z18XE. Basically the car will not start, getting flashing yellow triangle with the spanner through it when I turn the ignition on. I have read the code using an OBDII reader and it comes out with B3040 'communication malfunction on w-line'. Do you guy's have any ideas on what may be causing this ? The car has been stood for a good few weeks and the battery went totally dead. Charged it up 'after disconnecting leads' and then this error started coming out. It was fine before.

    Cheers

    WhiteGsd

  2. #2
    Status
    Offline
    badboysracing69's Avatar
    AOC Regular
    Join Date
    Nov 2006
    Posts
    228
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    Sounds like you've lost the earth for the ecu. I've had this problem before on a corsa 1.8 sri. It had a broken wire between the fuel pump relay and the ecu i think? I'll see if i can dig out the checks for you.
    Cheap Vaux mech at your service in Herts/cambs

  3. #3
    Status
    Offline
    whitegsd's Avatar
    AOC Newbie
    Join Date
    Sep 2008
    Posts
    3
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    cheers that would be great. Any ideas on where the fuel pump relay is located ?

  4. #4
    Status
    Offline
    badboysracing69's Avatar
    AOC Regular
    Join Date
    Nov 2006
    Posts
    228
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    Not off the top of my head. Check the wiring from the engine ecu. Trace it along and see if you can find a break somewhere. I'll look up the checks for the code tomorrow
    Cheap Vaux mech at your service in Herts/cambs

  5. #5
    Status
    Offline
    badboysracing69's Avatar
    AOC Regular
    Join Date
    Nov 2006
    Posts
    228
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    Sorry mate i did look this up but left the bit of paper at work. Basically the fuel pump relay and another relay i think is earthed by the ecu but i think this wire might be broken, causing you this code. In the relay box above the gearbox is the fuel pump relay i think?. Follow the wiring from this to your ecu and see if you come across a break. I think the terminal no.s are 29 and 35 on the ecu for the earths from these relays.
    Cheap Vaux mech at your service in Herts/cambs

  6. #6
    Status
    Offline
    whitegsd's Avatar
    AOC Newbie
    Join Date
    Sep 2008
    Posts
    3
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    Many Thanks for that. I had the car running for a while but it has stopped again with the same code. I have traced the problem to the main relay earth wire. Do you know which ECU plug & pin this wire connects to ? A diagram would be nice if you have one. I have temporarily earthed the main relay to the body work via a fused switch to get me up and running but a permanent fix is what I am after.

    Cheers

    WhiteGsd

Similar Threads

  1. Fitted a new lambda sensor bank 1 due to fault code p0135, now code has flashed again
    By Josh_GsiTurbo in forum Turbo Petrol Engines inc. Transmissions
    Replies: 16
    Last Post: 31-01-2012, 20:16
  2. 18XE1 coilpack - is a fault always shown by fault code?
    By oddsocks in forum NA Engines (Non-turbo petrol) inc. Transmissions
    Replies: 4
    Last Post: 05-11-2007, 22:56

Posting Permissions

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