Hi everyone, it's been a while, I am enjoying my resurrected XJS, I drive it every day, about 2 or 3 miles. The smoothness of the V12 is intoxicating. Anyway, I'm scared to go farther, the cooling fan hasn't been working. I finally jumped the two wires on the thermo switch and BINGO! FAN ON!!! Now, it seems impossible to reach and replace the switch, of course, but, what are the chances that the wires are reversed, on the switch. I know we spliced them together, they were chewed through by mice. There were 3 people working on it at various times, maybe we hooked them up backwards. Can I just reverse the wires?????? Would that hurt anything? The wire with the big plastic connector is on top, if that is helpful.

 

I don't think the e-fan switch is polarity sensitive. It's just an on-off switch. Switch open; switch closed; that's it.

Cheers
DD

 

Agreed.

When you joined them, the passage of lectrickery made no difference, the connection operated the fan.

Most of those switches are stamped at 85c, and that fan is designed as an "over temp" fan, and does not come on during "normal" driving conditions.

Bottom hose temp of 85c (where that switch is located), equates to APPROX 102c at the top hose, remember I said APPROX.

I use that 85c switch to operate dual thermo fans on all my V12's, and NO issues at 17+ years now.

 

I replaced my original 85C thermo switch with a new 82C switch. It makes me feel better that the electric fan will turn on at a slightly cooler temperature then the original switch... I also was not sure if the original was still operable so I made the change. It makes me feel better inside to have a new switch. LOL. The car runs like it should.

 

my fan died and I replaced it with a cheap $30 ebay fan that pulls even more CFM. My thermo switch broke so I just straight wired it.

My fans life won't be as long but its only $30 and I can very easily tell if its working. No guessing the temp. If the ignition is on I should hear the fan spinning. Works for me for now.

 

If you are only driving 2 or 3 miles a day then the engine probably isn't getting anywhere near the normal operating temperature; I don't think a lot of very short runs is going to do it a lot of good as it will be constantly running on a cold fueling setting.
Take it out and give it the beans for 20 miles, that should see if the fan kicks in.

 

Wow, thanks everyone for the replies. I'm going to straight wire the fan, when I turn the key, the fan will come on, and, keep running. To paraphrase DOUG, case opened, case closed.

 

Oops, I just posted concurrently with STEVE M. Yes, you are right, I am scared to drive it very far, it might overheat. But, how will I ever know the thermo switch works if I don't heat it up? Remember, I rescued this car from a field where it sat for 4 years, it only has 63,000 miles on it, and, wasn't running all those years. When I drive it, I'm watching the temp gage more than the road.

 

gthawk1,

You could try testing it as you might do a thermostat using a thermometer immersed in a pan of heated water. See similar thread here:

https://www.jaguarforums.com/forum/x...estions-97737/

Paul

 

the device in the following article might help you. it has a digital readout and can control a relay at temperatures of your choosing:

AutoSpeed - $25 Temperature Controller and Display!

on ebay make sure you get the metric version as it has a more suitable operating range, and get the 12vdc version, not the 120vac version.

 

PLUMS, yes, that temperature controlled switch is exactly what I need. Thanks. I didn't even know there was such an animal.

 

STEVE M 58 Degrees F, clear, perfect Jaguar weather. My wife and I put the hood down and GAVE IT THE BEANS. We drove it about 20 miles! What a great car. Why doesn't everyone have a V12? Stopped at a friends, his wife climbed on the hood...no camera...had another friend drive it, and, converted him...to V12 power. And, the needle never really went above N, as a matter of fact it stayed below N all night, uh, except when Edie climbed on the hood, then it went up. Anyway, I hate to ask, but N...N? What does N stand for?

 

HAHAHAHA, Faith in a V12, LUV it.

"N" is British humour for NORMAL. Fair dinkum, "what is normal anyhow".

You, sir, are now fairly smitten with the pleasures of real motoring, and the V12 is the ONLY way to do it.

Bugga, I miss mine more now, time for a drink, see ya.

 

DUDE CHECK THE FUSE. SMALL WHITE BOX ON DRIVER'S SIDE ENGINE COMPARTMENT. 10A. Change it, usually blows.

 

N = Not hot, Not cold.
simples.

 

"Edie climbed on the hood...." Thank you for not correcting me, I mean the bonnet, as I used up the word "hood" earlier. I have my Owner's Manual open to the English to English section. I was hoping no one would say N meant Neutral, as that was already used up, by the transmission. Thank you.

 

Everything in my entire auxiliary fan circuit has failed except that fuse, don't talk about that fuse.