Rad fan not switching off

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vdubchris1992

Rad fan not switching off

Post by vdubchris1992 »

My rad fan I discovered was unplugged when I got my van on the sensor near the bottom of the rad behind the lower grill. I plugged it in to try it but knew it must have been unplugged for a reason. It comes on at a suitable temp but even when the van cools right down it stays running. Even with engine off. I have it hooked up to a switch temporarily but just wondering if this is a common fault. Maybe it''s the sensor in the rad or maybe a relay is latching open somewhere or something silly like that. Anyone had this? Thanks guys.

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itchyfeet
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Re: Rad fan not switching off

Post by itchyfeet »

yep change switch, easy job, get one from Brickwerks to be sure of good quality, cheaper then VW heratige too.

do it quick and you loose almost no coolant so no need to bleed, need to remove lower grill and remove radiator baffles.
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vdubchris1992

Re: Rad fan not switching off

Post by vdubchris1992 »

Ahh cool. Thanks. Was hoping for just the switch. I have various jobs to do on the cooling system so will be draining it anyway.

Da dan
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Re: Rad fan not switching off

Post by Da dan »

Would that blow fuses too? Sounds similar. What is the switch called? As I should try that?


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itchyfeet
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Re: Rad fan not switching off

Post by itchyfeet »

my guess is blowing fuses is motor problems ( drawing too much power) not the switch, thermswitch in rad to turn fan on and off as required
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Re: Rad fan not switching off

Post by CovKid »

If its blowing fuses, look above the earth crowns under dash and you'll see a relay on the bulkhead on a bracket. This is the high-speed relay for rad fan. What happens is the terminals on the relay get corroded. I had this prob for almost a year (blown fuse) before I unseated the relay and refitted it - problem vanished.
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Re: Rad fan not switching off

Post by pirate-pete »

Think it will just be the switch as if the fuse was gone it would not be coming on.

Mine went same way with fan coming on on full speed one day when parked up with engine cold. Had to remove fuse to stop it. Until I got the new one fitted (5 min job) I was running without the fuse fitted. But able to pop it back in if I was stuck in traffic.

Only time I've ever heard the fan come on full speed since then was last summer in France when temps in the mid 30's.
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itchyfeet
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Re: Rad fan not switching off

Post by itchyfeet »

there are two different problems here, the OP and a hijacker :D
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Re: Rad fan not switching off

Post by pirate-pete »

Ahhh - I'm a bit slow tonight. :run
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Da dan
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Re: Rad fan not switching off

Post by Da dan »

Would a poor earth create the same problem too? I changed the relay already but have to say it worked the first time I brought it up to temp. All the earths there need some love. But still popping fuses? I have resulted in taking out the fuse too


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Da dan
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Re: Rad fan not switching off

Post by Da dan »

Da dan wrote:Would a poor earth create the same problem too? I changed the relay already but have to say it worked the first time I brought it up to temp. All the earths there need some love. But still popping fuses? I have resulted in taking out the fuse too


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Any ideas?


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