Car running hot fan doesn't come on

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Jul 12, 2005 | 03:26 PM

Dodger2940

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From: beware of the 909

Car running hot fan doesn't come on

This happened to me last year and I changed the Fan, thermoswith and thermostat. Now its happening again.

I changed the fan with a Fal fan. Can these go bad so soon? I changed to a OEM thermostat and a mugen fan swith. NOw its the summer time and the car is running hot. What can be the problem? Do I need a new radiator??

The car is a 2000 civic Si.

Jul 12, 2005 | 03:38 PM

Russ713

dAng!

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From: alabama/florida

Re: Car running hot fan doesn't come on (Dodger2940)

hot wire the fan to see if it works. That will help determine a faulty thermo switch.

The radiator should technically be fine, but there's always one out there that likes to get clogged or go bad. You can try flushing it or having a radiator shop clean it out completely. That or swap it if you have one available.

Jul 12, 2005 | 03:41 PM

Dodger2940

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From: beware of the 909

Re: Car running hot fan doesn't come on (Russ713)

Do thermo switches go bad so fast??

Also whats the best way to hot wire the fan? I have read that turning on the Air will turn on the fan. Is this right?

Jul 12, 2005 | 03:44 PM

Russ713

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Re: Car running hot fan doesn't come on (Dodger2940)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dodger2940 »</TD></TR><TR><TD CLASS="quote">Do thermo switches go bad so fast??

Also whats the best way to hot wire the fan?</TD></TR></TABLE>

It could be a faulty thermo switch. However, to hot wire the fan, there's two wires coming from the fan to a plug. Disconnect the plug and connect two wires to the battery. (pos and neg)

Jul 12, 2005 | 03:49 PM

Dodger2940

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From: beware of the 909

Re: Car running hot fan doesn't come on (Russ713)

Ok thank you will do tonight.

Jul 12, 2005 | 03:50 PM

Russ713

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From: alabama/florida

Re: Car running hot fan doesn't come on (Dodger2940)

best of luck

Jul 25, 2005 | 03:50 PM

2000si B16A2T3

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From: Phoenix, AZ, USA

Re: Car running hot fan doesn't come on (Dodger2940)

I got the same car, first thing to check is the radiator fan relay. It is under the hood in the fuse box on passenger side of car. Its the third fuse like black plastic looking thing up from the front of the car......(lol) on the right side of fuse box, and there should be a total of four(4) of em. Is your A/C condenser fan coming on? If it is just switch the A/C condenser fan relay (1st one closes to front of car) with the radiator fan relay and see if the fan comes on now. Make sure you have the A/C turned off when you are doing this, and never pull the relay while the car is running. If it is not the relay then go from there, but didnt want you to replace everything else just to have the prob be the relay, lol. Good luck to ya.