Page 1 of 1

Radiator Fan Stays on all the time!

Posted: 13 Jun 2008, 01:19
by calmurphy
Hello this is my first post and time on the forum, My Fan worked fine until i took it to a garage to have some work done . after a few weeks I noticed my fan fuse had disappeared. When i put one in the fan stayed on permanently.
I thought it was obviously the thermo switch , so I replaced it . The fan still stays on , so I have to connect it manually now, when I think the van is getting hot. any ideas? :roll:

Posted: 13 Jun 2008, 07:25
by ermie571
Welocme to the nut house

Can't help with the fan thing, sorry!

Em
x

Posted: 13 Jun 2008, 07:28
by toomanytoys
Did the garage do any work on the rad etc???

sounds like there is a damaged wire in the loom.. or someone has fitted a seperate switch to operate it... or someone has cut the wires and reconnected them wrong...

Posted: 13 Jun 2008, 07:28
by kit
In 4 years my fan has only come on once, so I am of no help either.

Posted: 13 Jun 2008, 07:31
by syncrosimon
just thinking aloud...

I can only think it is the thermo switch, on the radiator, but if you have replaced it then...I cant imagine what has happened. The live feed from the fuseboard goes to the switch, which then either switches it off or on. You must have a short out after the thermoswitch. it would be worth checking with a multimeter the condition of the wires, but if the fan stops when you pull the fuse, then the power is coming in in the correct way. Have they accidentally cut the wires going to the thermo switch, and put them back the wrong way around??
What did the garage do to the van, were they working at the front??

P.s welcome to the forum.

Re: Radiator Fan Stays on all the time!

Posted: 13 Jun 2008, 07:48
by Grun
Hello calmurphy,
Welcome to the forum.
:D
Now, some (later model?) vans have a two stage radiator fan which runs via two fuses and through a relay for the second stage. The thermo switch is a two stage as well. First stage is slow and quiet, second stage fast and noisier.

If the relay is faulty, (contacts always closed) then the fan would run (continuously) in the second stage even with a good thermo switch.
Doesn't seem very likely 'cause I would have expected the relay to fail 'open circuit' but who knows?

Fuses are 30 amp first stage 50 amp second stage. Relay (if fitted) should be fifth from left, top row of the fuse box.

If it were me I would be having a word with the garage.

Mike

Posted: 14 Jun 2008, 00:20
by Virginiahaze
ermie571 wrote:Welocme to the nut house

Can't help with the fan thing, sorry!

Em
x

Posted: 14 Jun 2008, 22:25
by Simon Baxter
Does it still run when you disconnect the plug from the switch?

Or, has some numpty put an extra switch somewhere, what people seem to call a manual overide switch!
What manual overide switch means is "I don't know what the f**k I'm doing, and rather than spend a few quid repairing it I will spend more money making the job worse, and waste a load of time running wires to the dah, drilling the dash for a switch."
I'm sure you will agree that it takes longer and costs more money to do the "Manual overdie" than just fix the original problem.

Most electrical problems are down to human interfearance.

Re: Radiator Fan Stays on all the time!

Posted: 15 Jun 2008, 17:55
by campervanman
What was the work that the garage did in the first place?

Re: Radiator Fan Stays on all the time!

Posted: 15 Jun 2008, 23:54
by calmurphy
campervanman wrote:What was the work that the garage did in the first place?

They changed the radiator , and a few other jobs to get it through an MOT . It ended up being in the garage for 3 months long story!!! i finally got it back 2 days before I was going away to France in it . I never went back because I wanted my van , not in there any longer. Would it stay on if they wired the plug wrong?
( i usually fix things myself, but was so busy at work, ) wiring diagrams make me dizzy.

Posted: 16 Jun 2008, 00:14
by calmurphy
Simon Baxter wrote:Does it still run when you disconnect the plug from the switch?

Or, has some numpty put an extra switch somewhere, what people seem to call a manual overide switch!
What manual overide switch means is "I don't know what the f**k I'm doing, and rather than spend a few quid repairing it I will spend more money making the job worse, and waste a load of time running wires to the dah, drilling the dash for a switch."
I'm sure you will agree that it takes longer and costs more money to do the "Manual overdie" than just fix the original problem.

Most electrical problems are down to human interfearance.

Hi Simon , I know the fan was working fine until it went the garage. Above the fuse is a relay that is called the x load reduction (what does that mean?) i pull that out and the fan still runs . I havent tried pulling the plug out , so I will try that . Although I can not see any evidence of another switch being fitted.
Thanks

Posted: 16 Jun 2008, 16:04
by edoh
have you cleaned/checked fuses/fuseholder?
wiring to the rad/switch?

give everything a really good clean and see if that makes a difference -

my rad fan stayed on - til i did the above - which seems to have cured the problem -

Posted: 18 Jun 2008, 17:28
by clartsonly
[quote=baxter]
What manual overide switch means is "I don't know what the f**k I'm doing, and rather than spend a few quid repairing it I will spend more money making the job worse, and waste a load of time running wires to the dah, drilling the dash for a switch."
I'm sure you will agree that it takes longer and costs more money to do the "Manual overdie" than just fix the original problem.
[/quote]

I understand what you are saying and perhaps in the context of a camper van you are correct, but I fitted a manual override to our fiat cinquecento 1996 900cc, and that was the correct thing to do the usual operating temperature was 80 degrees the fan did not cut in util 110 degrees and when sitting in traffic head gaskets go, the thermostats break and the water pump seals go, not to mention the problems with the heater matrix letting water through under the pressure. You might well say replace everything in the engine and then it will hold the pressure but most little fiats simply break. a manual override is not always such a bad thing, saying that though since fixing the radiator fan issue on my camper I have only ever known it to come on once.