Page 1 of 1
Low voltage at fan switch?
Posted: Tue Jul 16, 2013 3:44 pm
by Duck
Hi folks, the bike started getting hot (hotter than usual) in traffic so I decided to flush and replace the coolant and give the rad a bit of a clean, now its all back together the fan doesn't come on, I tested the voltage on the switch wires and its floating around 3v? Should it not be 12v? I haven't put any voltage straight into the fan to check that's working properly yet as I ran out of time but will try tomorrow, Just seems strange to have 3v there or is that right?
I'm not much of an electrician so any advice is welcome.
Thanks in advance.
Re: Low voltage at fan switch?
Posted: Tue Jul 16, 2013 4:37 pm
by banner001
the voltage flowing should be dependent on the temperature, what temperature did yo test at? ill stick my multimeter on mine this evening if i remember.
Re: Low voltage at fan switch?
Posted: Tue Jul 16, 2013 7:31 pm
by Duck
From just half way on the gauge till over 3/4.
Re: Low voltage at fan switch?
Posted: Tue Jul 16, 2013 11:17 pm
by banner001
hmm, that does seem off, im sure the voltage should increase over temperature, and at that temp the fan should be on...sorry, its late now, ill test mine at cold in the morning, and maybe get to test it when warm/hot tomorrow evening.
Re: Low voltage at fan switch?
Posted: Wed Jul 17, 2013 12:14 pm
by Duck
Ok it defies all logic but it's fixed it's self....
Came out today pulled the tank and air box off to get to the fan connector, wired it to the battery and it spun.
Checked the wiring diagram for the fan circuit it goes; battery - 30A fuse on starter relay - 10A fuse in the box - fan switch - fan - ground, I checked the voltage at each point and it's just over 12V all the way, Can't figure out what was going on yesterday maybe I was in the sun too long or had 1 too many beers or both but anyway it seems fine now.
Thought I'd check the resistance on the fan switch just to make sure and, it's dead, I can't get any readings off it from cold to nearly boiling over, rang Cradley for a price they said £63.94 + vat!!! bit pricey to say the least.
What's your thought's on wiring in a standard switch somewhere to turn the fan on manually?
It's a bit of a bodge but I cant see why it wont work till I get it sorted properly.
Re: Low voltage at fan switch?
Posted: Sun Aug 18, 2013 3:24 pm
by ross46
Will be fine as an interim fix, but the problem is that if the bike is hot, even when you turn the bike off the fan will keep going, if you dont wire it properly as soon as you turn the bike off the fan will stop and might blow your head gasket, just make sure you wire to a permanent live
