Problem with ACC power controller

  • Hi gang/Sergey,


    Wanted to ask if anyone else had a problem with their ACC power controller not working anymore.

    I had it installed a while ago and it worked as it should. But now I just installed the Automatic Roll up windows controller + Key fob (harness was rewired for RHD) and the ACC power controller stopped working. The radio will now switch off as soon as I turn the ignition off.


    I also have the DRL harness installed but I wouldn't think this would affect anything.


    Anyway, has anyone who bought the ACC power controller and auto roll up window controller encountered this problem at all? Looking for solutions if possible lol.



  • It could be an issue with the RHD harness, bad connection from door contact. Could you try to remove the RHD harness and also check if all contacts on the harness are populated the same way as on the car cable?

  • I just fitted the ACC Power Controller on my 2020 MX-5 RHD and the key fob cannot be inititialised to the start button. No green light no car start. Take the part out and it works, put it back and I can't start the car. There appear to be issues?

  • @Phil Baugh This could happen if harness has bad connection on some wire, this unit need to be replaced need to be replaced

  • Many thanks, I have requested a replacement from my supplier. 

    On another matter, could you tell me when the 3 wire windows controller key fob wiring will be available for the UK market too, please?

    It should look like this, in my opinion.

    UK Key Fob Wiring

    There is an extra wire required over the currently available part.

  • @Phil Baugh we don't supply them anymore, because RDH cars have two wiring options, hard to guess which one must be supported. Instead we have a simple cable with Posi-Taps, which will work on any car.

  • @mx5things An update, I fixed it up now. I had a look at the replacement kit you sent me, there doesn't seem to be any difference with the cabling at all. But I unplugged ACC power controller, then plugged in oem plug, booted up the car and then switch off. Then repluged the ACC power controller and now everything is working fine. I didn't test if this work by itself. So I didn't end up testing if it was bad wiring on my part as I installed your replacement parts. 


    I think what might've happened is my diagnostic tool deleted some CAN error or something. But plugging back in OEM then ACC controller seemed to reset the "error" for it to work?


    Anyway, thanks for replacement part. Top bloke.

  • Hi there, 

    I didn't want to create a new thread as I too am having issues with the ACC controller. When I plug in the harness, only one ignition light  comes on (flashing red key.)

    This is my second unit as I had the same problem with the first one. Although there were some differences...

    First unit : Installed in minutes, but five\six beeps from the car and no lights and no engine start

    Second unit :  Installed in minutes, no beeps, no lights (bar the same flashing one) and no engine start

    I can’t believe I'm that unlucky to have two faulty units. 

    I’m installing this in a UK, RHD Spider. Any ideas?


  • @Steve Capon, unfortunately, there are bad crimping issues in the first batch of cables, which will produce these effects. I can ship a replacement directly, please contact

  • Thanks for the quick response. Will email. Steve

  • @Steve Capon It will be a faulty unit. I had two do slightly different things, one wouldn't allow the car to start at all & the other wouldn't  allow the engine to start without touching the key to the ignition, & the car couldn't be locked. Bad batch, get one direct from Sergey, that will work fine.

  • @Phil Baugh thanks Phil. That's reassuring! Will report back here when sorted!

  • @mx5things Many thanks for the quick response and despatch of the replacement unit which took me less than five minutes to install and works perfectly. Great customer service!


Please login to reply this topic!