1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

ECU Relay replacement

Discussion in 'T3 & T4 Tech Help Clinic' started by beerboy, Nov 11, 2019.

  1. beerboy

    beerboy Well-Known Member

    Messages:
    1,037
    Location:
    Sydney
    Not sure if I am going mad here trying to find a new ecu relay. Is it anything special. mine does not have a number on it which seems to be the normal procedure for identifying them.
     
  2. syncro

    syncro Well-Known Member

    Messages:
    9,640
    Location:
    Southern Highlands
    There should be a 9 digit VW number on it. I am not sure but these may be a standard generic relay.
     
  3. Luckyphil

    Luckyphil Well-Known Member

    Messages:
    6,556
    Location:
    Gosford
    The ECU relay is NLA however there is a workaround so you can use a 57 which is the same as the fuel pump relay sitting next to it. I have the workaround procedure at home so will post later this afternoon. A word of warning when removing these relays to disconnect the battery as you can fry your ECU. This is good practice whenever you work on the electrical system.
     
    Grantus likes this.
  4. beerboy

    beerboy Well-Known Member

    Messages:
    1,037
    Location:
    Sydney
    still confused you mean 53 relay? thanks phil and phill. when you get a chance
     
  5. Luckyphil

    Luckyphil Well-Known Member

    Messages:
    6,556
    Location:
    Gosford
    It prob is a 53 for the fuel pump I was running from memory. So this fix will allow you to have both relays the same. In essence what you need to do is change the pin wiring in the plug to work with a 53 just plugging one in will not work. I believe earlier T3's did use 2 of the same relays but for some reason VW change the relay for the ECU to also have a resistor which is what burns out. The function of the van will be the same after the mod.
     
    Grantus likes this.
  6. beerboy

    beerboy Well-Known Member

    Messages:
    1,037
    Location:
    Sydney
    thanks phil for the clarity :)
     
  7. Luckyphil

    Luckyphil Well-Known Member

    Messages:
    6,556
    Location:
    Gosford
    Syncro27, Wayne murray and Grantus like this.
  8. beerboy

    beerboy Well-Known Member

    Messages:
    1,037
    Location:
    Sydney
    Thanks phil that is a very good document that someone has updated! great wiring diagram. Thats why I am confused then. that relay is a bit of a non starter to start with. will order a couple of 53 relays from brickwerks.

    from the samba

    "The switch to the special 5 pin ECU relay was done to implement the Calif CARB mandated emissions OBD. This mandate was then delayed just before it was to go into effect. So VW switched back to a standard 4 pin ECU relay for the last couple years after 88/89. Of course the last couple years wiring diagrams wrongly still show it, another source of confusion for people trying to resolve tricky problems."
     
    Last edited: Nov 11, 2019
  9. beerboy

    beerboy Well-Known Member

    Messages:
    1,037
    Location:
    Sydney
    just to follow up. the brickwerks 53 relay has a sticker on it. so any 40 amp relay will do I think. Do not think it is anything special :) still half the price from brickwerks
     
  10. syncro

    syncro Well-Known Member

    Messages:
    9,640
    Location:
    Southern Highlands
    This may be to stop transient currents damaging the ECU.
     
  11. Luckyphil

    Luckyphil Well-Known Member

    Messages:
    6,556
    Location:
    Gosford
    Is that what causes Vanagon Syndrome?
     
  12. syncro

    syncro Well-Known Member

    Messages:
    9,640
    Location:
    Southern Highlands
    Nope.
     
  13. beerboy

    beerboy Well-Known Member

    Messages:
    1,037
    Location:
    Sydney
    no thats more on a errant signal getting to the AFM is it not.
     
  14. syncro

    syncro Well-Known Member

    Messages:
    9,640
    Location:
    Southern Highlands
    Yes,
     
  15. SunnyJim

    SunnyJim Well-Known Member

    Messages:
    1,869
    Location:
    carindale Brisbane
    Coincidence... I thought my t3 fuel pump went bad but it was the one next to it. Replaced and all good now!
     
  16. syncro

    syncro Well-Known Member

    Messages:
    9,640
    Location:
    Southern Highlands
    That really does sound like an urban myth.
     
  17. beerboy

    beerboy Well-Known Member

    Messages:
    1,037
    Location:
    Sydney
    yes I heard it on the internet. thread is here http://forums.kombiclub.com/threads/ecu-relay-replacement.58875/

    crazyvwman has been posting lots of good info from when I was tracing a no start. Nothing really that strange now with the vanagon and no engine management. who would believe vanagon syndrome is fixed by a 300 dollar pigtail. why would anyone go Subaru :eek:
     
    Luckyphil likes this.
  18. Luckyphil

    Luckyphil Well-Known Member

    Messages:
    6,556
    Location:
    Gosford
    It is also fixed by adding a 30c resistor or capacitor(cant remember which) into the AFM
     
  19. beerboy

    beerboy Well-Known Member

    Messages:
    1,037
    Location:
    Sydney
    capacitor I think. yes done that one. I paid 150 for the adapter. happy with that rather than the bucking, loss of power and plumes of black smoke on the F1 freeway by the massive cutting. I remember it well :)
     
  20. syncro

    syncro Well-Known Member

    Messages:
    9,640
    Location:
    Southern Highlands
    VW was giving them out for free for a while.
     

Share This Page