Ooops wiring problem, HELP!

kris_aka_edu · Post by **kris_aka_edu** » Tue Jul 16, 2013 10:23 pm

As described in a bit of a state now!

As some of you may know my radiator blew a little while ago, and never had any fans on the new one. I decided to order myself a universal fan off ebay. It arrived with no problem.

Me and my mate decided to give it a go wiring it up. Ended up being a complete catastrophe! Before I started everything worked fine, I even had a Volt meter in my tweeter which me and @ddoubledanny installed last weekend.

We put the fan on, as its only a 10inch fan we cable tied it to the radiator, I'm not really fussy about looks, as long as it does the job I'm happy.

We fed the wires from the fan back to the cabin, through a hole which is used for the air duct where the air con used to be. I knew there was a sneaky little hole there already. Not a problem.

Then my mate wired it all up behind the stereo using the wires from the power source and he got the fan working. We then decided to earth it and put in a fuse. Next step was to put it on a switch. The switch then didnt want to work. After a little while of trying to work out why it wasnt working we checked the fuse. It had blown, (not the one we had installed) but the 15amp fuse for the stereo in the fuse box. I went to put another one in and bang! It blew straight away, tried again and bang. We fiddled with the wires for around 2 hours. I got so pissed off with it I wripped out all the wiring that we had installed and put it back exactly like it was before. Put a fuse in and bang! Now I cant put a fuse in to get the stereo working, nor does volt meter work. I don't understand whats going on as it worked perfectly fine before?!

I've tried all different amp fuses, 10s, 15s, 20s and 25s, every one blew as soon as I put it in with a bright spark and a puff of smoke. I'm no good with electrics and my mate has loads of experience with electrics and cant seem to work out why its doing it?!

I'm really stuck as I still have no fans so my engine could over heat when stuck in traffic in this hot weather and now not stereo or voltage meter.

Any ideas what so ever would be much appreciated as I'm furious now as it all worked before! I'm hoping I'm not going to have to re-wire the whole fuse box. All the other fuses are working fine the clock works fine, and I assumed the clock worked off the same fuse?

Would any one be willing to come and help me on Sunday? This is the only time I've got to fix all this now

Post by **Gayno** » Tue Jul 16, 2013 10:34 pm

Quite frankly, these fans pull a lot of amps and you shouldn't be using the stereo feed for them.

Wire them direct to the battery, with their own fuse (the required rating should be listed in the documentation with the fan) via a relay which is activated by the switch in the cabin.

However, you could just use the existing fan wiring, that way it is controlled by the thermostat as it should be.

Why do a botch job with a switch hen you can do it properly?

kris_aka_edu · Post by **kris_aka_edu** » Tue Jul 16, 2013 10:38 pm

I don't have the old connections from the old fans. I just preffered being able to turn it on and off when I wanted so I knew it worked rather than hoping it still worked when it starts to over heat.

Only trouble is mate is that now I've put everything back together with nothing connected apart from what it was originally like before I messed around with it, its now blowing any fuse I put in there! So now the head unit wont work or the volt meter.

I'm so confused!

mercutio · Post by **mercutio** » Tue Jul 16, 2013 10:41 pm

where the wiring goes through the bulkhead has the wiring chafed? did you disturb any other wiring when you earthed the fan sounds like your wiring in the fan has disturbed something elsewhere

kris_aka_edu · Post by **kris_aka_edu** » Tue Jul 16, 2013 10:49 pm

We've checked everything behind the head unit itself and all looks Ok. We didn't tap it to anything else apart from the ISO I think its called? Directly from the stereo. Cant work out what's wrong at all. Really dont want to wrip out the whole dash or anything. I've got no idea what I'm doing and would really appreciate some help if some one could come round and help me and my mate? Some one who knows a lot about electrics in cars. Willing to pay or help as a favour in return.

mercutio · Post by **mercutio** » Tue Jul 16, 2013 10:58 pm

I don't know a lot about electrics but I would check out the iso connector if that's where you tapped in as that sounds like ground zero I am also too far away sorry

Post by **4thgenphil** » Tue Jul 16, 2013 11:10 pm

i suspect you may have blown the fuse to the stereo, which is probably where the feed to the volt meter is tapped into. check the 10 amp fuse for the stereo my bets its blow!

as for the fan wiring, its easy man! you dont need the old connector from the fan just the 2 wires from the car to it!

as for turning it on and off when you want with no thermal control, thats just asking for a new head on your car! the one time you forget to switch it on will kill it!

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Wed Jul 17, 2013 12:44 am

I agree with Phil and Gayno on the fans - just run it off the original plug so it cuts in/out automatically when it should. If you just unplugged the original fans when you removed the old rad, they'll still be there. Can't remember which side plug it is that you should pick up from (drivers side/pass side) iirc one is for A/C which you don't want and the other is the normal engine temp fan (which you do want).

Also agree with others that it sounds like a dead short on the wiring to the radio (i.e. 12v goes straight to ground). How did you tap into the wiring for the fan? Any pics? Does it still blow the fuse if you unplug the iso connector from the back of the stereo?

Trying higher rated fuses is not a good idea I'm afraid - it just means the wiring can pull higher current than it was designed to before blowing the fuse and the result is melted wiring and possible fire (I've seen it happen...)

kris_aka_edu · Post by **kris_aka_edu** » Wed Jul 17, 2013 8:34 am

Yeah I've had a fire before and it's kind of worrying.

I can't put in any fuse at all as soon as it touches the fuse box it blows.

Any one local and willing to come down Sunday to have a look for me?

Post by **ddoubledanny** » Wed Jul 17, 2013 10:32 am

As others has mentioned mate you have either a wire split shorting out to earth causing the fuse to pop or the fan is pulling to much load for the setup and causing a fuse to pop