Rad fan override switch
Posted: 03 Jul 2007, 20:59
Whats the easiest way to wire in a switch to run the rad fan , overiding the thermo switch?
Mike
Mike
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Rad fan override switch
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Posted: 03 Jul 2007, 21:02
Take a jumper off the thermo switch 12V feed wire, to a switch and back to the other terminal on the thermo switch. Make sure you use heavy gauge wire, there`s some amps running through there.
Posted: 03 Jul 2007, 21:12
Many thanks, I have wiring diagrams for most models but not 1.6 n/a, anyone have a link to one? as I would rather take it from the fusebox
Mike
Mike
Posted: 03 Jul 2007, 21:31
wire the fan up direct from the battery?
Posted: 03 Jul 2007, 21:38
Are these single or twin speed?
Mike
Mike
Posted: 03 Jul 2007, 22:06
Mine is twin speed, 2nd speed runs through a relay I think, sounds like a 747 taking off when you jump the switch wires. 
If you wire like I said earlier you use the original feed wires etc so save running more feeds etc. To try it out get to the thermo switch behind the grill, pull the plug off and there will be 3 wires (if it`s 2 speed anyway). Use some 30 amp cable with a apir of male spaded terminals on it and try jumping a pair of wires together until you find which is the 12V feed and which is the other one to make the fan run, can`t go wrong really. Then wire it from there, make sure the wires and switch can take the amps. I would use 50 amp cable to be safe.
If you wire like I said earlier you use the original feed wires etc so save running more feeds etc. To try it out get to the thermo switch behind the grill, pull the plug off and there will be 3 wires (if it`s 2 speed anyway). Use some 30 amp cable with a apir of male spaded terminals on it and try jumping a pair of wires together until you find which is the 12V feed and which is the other one to make the fan run, can`t go wrong really. Then wire it from there, make sure the wires and switch can take the amps. I would use 50 amp cable to be safe.
Posted: 03 Jul 2007, 22:39
Ok, will get my meter out tommorow and try it
Thanks Mike
Thanks Mike
Posted: 03 Jul 2007, 23:14
Don't quote me, but I've been told they are 3 speed. Slow, High, and Panic. I would ass-ume that means the resister switch is low on one side, high on other side, and panic on both???
Hopefully someone who knows these electronics will be along to verify or deny my none quote.
Lloyd
Hopefully someone who knows these electronics will be along to verify or deny my none quote.
Lloyd
Posted: 03 Jul 2007, 23:16
double post...
Lloyd
Lloyd
Posted: 03 Jul 2007, 23:29
Not heard that Lloyd, but its as good a label as anything to put on the switch
mike
mike
Posted: 03 Jul 2007, 23:49
I've used other 3 wire fans that did work as I described... that doesn't mean our vans do ... 
Posted: 04 Jul 2007, 10:24
Are we trying to cure the symptom rather than the disease ?
I'd be asking why it's getting hot in the first place. Having said that in very hot conditions (40+ in one Brittany traffic jam) I stuck our heater on hot and the fan on 3 for a minute or 2. that worked before the fan even cut in.
Ian.
I'd be asking why it's getting hot in the first place. Having said that in very hot conditions (40+ in one Brittany traffic jam) I stuck our heater on hot and the fan on 3 for a minute or 2.
that worked before the fan even cut in.Ian.
Posted: 04 Jul 2007, 20:05
No ,no problem as such, but Thermo switches have a habit of going wrong and often just when they're needed so its good to have a manual overide.
Also as this is an asmatic 1.6d and when we go over to Ireland in the height of summer(well maybe not too hot this year) there are some long long hills/mountains that are crawls in 2nd gear so running the fan to help compensate for the lack of airflow does help,
Mike
Also as this is an asmatic 1.6d and when we go over to Ireland in the height of summer(well maybe not too hot this year) there are some long long hills/mountains that are crawls in 2nd gear so running the fan to help compensate for the lack of airflow does help,
Mike