Wiring an aftermarket electic fan... four relays? which one?
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Wiring an aftermarket electic fan... four relays? which one?
ok, so I was trying to wire my fan to the stock control unit... but there are 4 of them... slightly confusing.... I think I may just wire it into the ignition instead....
if I wanted to wire it in so that it kicked in when the ecu wanted it to where would I go? seems the relay 3 is the correct one on the L/O wire... but I want to be sure.
if I wanted to wire it in so that it kicked in when the ecu wanted it to where would I go? seems the relay 3 is the correct one on the L/O wire... but I want to be sure.
Are you wiring a new independent fan or an aftermarket fan for the radiator? Here is how the stock system works:
When the relays come on:
* Relays 2 & 4 controlled by PCME, come on when temp reaches 221F.
* Relay 3 controlled by thermoswitch, comes on at 226F
* Relay 1 controlled by A/C switch.
How fan speed affected by relays:
* Off, none on
* Low speed comes on when relays 2 & 4 are active.
* Med speed comes on when 2 & 4 are on plus _either_ 3 or 1 comes on but not both
* High speed comes on when all are on.
Other facts:
* The fan controller can bypass the 226 thermoswitch and fake out the relays 2 & 4.
* Grounding the test lead _immediately_ turns on relay 3.
* When you ground the test lead then the fan controller waits 2 min and turns on 2 & 4.
* If the test lead grounded for 2 minutes before engine shutoff, relays 2,3,4 will be kept on.
* Relays 2 & 4 controlled by PCME, come on when temp reaches 221F.
* Relay 3 controlled by thermoswitch, comes on at 226F
* Relay 1 controlled by A/C switch.
How fan speed affected by relays:
* Off, none on
* Low speed comes on when relays 2 & 4 are active.
* Med speed comes on when 2 & 4 are on plus _either_ 3 or 1 comes on but not both
* High speed comes on when all are on.
Other facts:
* The fan controller can bypass the 226 thermoswitch and fake out the relays 2 & 4.
* Grounding the test lead _immediately_ turns on relay 3.
* When you ground the test lead then the fan controller waits 2 min and turns on 2 & 4.
* If the test lead grounded for 2 minutes before engine shutoff, relays 2,3,4 will be kept on.
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From: San Luis Obispo Ca.
so..... sounds like ignition..
I bought a 12" "slimline" type fan... it's mounted and I've had it hooked up to the ignition wire, but I'm playing with the idea of hooking it to the fan relay... but it seems like it may be more trouble than it's worth... I'm fine with it hooked up running when the ignition is on... It doesn't get cold here..
I bought a 12" "slimline" type fan... it's mounted and I've had it hooked up to the ignition wire, but I'm playing with the idea of hooking it to the fan relay... but it seems like it may be more trouble than it's worth... I'm fine with it hooked up running when the ignition is on... It doesn't get cold here..
The absolute best way to do an aftermarket fan setup is to go standalone. Buy two Pemacool 90002 fans and a csi temperature controller. That is all you need. You set the temperature where you want to run it from inside the cabin and the gauge does the rest. Throw in a light to let you know the fans are running and a warning light when the temperature trips at 200f. All three if my cars are setup this way.
later
later
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I have a microtech lt10-s and was wondering how would I get all for relays to kick in at once I have it connected to relay #4 will that make all 4 relays kick in? Also which fan is suppose spin faster the 4 or 5 blade fan?
What did you mount the fan to? Is this an IC fan, or a replacement fan for the radiator? 1 12" fan won't be enough for the radiator.
If it's the IC, I'd assume you'd just want to run it all the time, and/or just wire it to a switch. No need to follow the rad fans.
If it's the IC, I'd assume you'd just want to run it all the time, and/or just wire it to a switch. No need to follow the rad fans.
so..... sounds like ignition..
I bought a 12" "slimline" type fan... it's mounted and I've had it hooked up to the ignition wire, but I'm playing with the idea of hooking it to the fan relay... but it seems like it may be more trouble than it's worth... I'm fine with it hooked up running when the ignition is on... It doesn't get cold here..
I bought a 12" "slimline" type fan... it's mounted and I've had it hooked up to the ignition wire, but I'm playing with the idea of hooking it to the fan relay... but it seems like it may be more trouble than it's worth... I'm fine with it hooked up running when the ignition is on... It doesn't get cold here..
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RX7Junkman,
the stock relays will not work without the ECU controlling them, thus no fans
you'll need to wire in your own relay and run a switch to the fans or do a setup similar to what baddrx7 is talking about
joeydinc,
don't run the fans all the time by having them come with the ign. - your car will take longer to warmup and you will wear your fans out 10times faster (ask me how I know)
if you are talking about an aftermarket fan, then you will not be able to control it with the stock relay syst. - aftermarket fans are not made to run at variable speeds like the stock fans
the stock relays will not work without the ECU controlling them, thus no fans
you'll need to wire in your own relay and run a switch to the fans or do a setup similar to what baddrx7 is talking about
joeydinc,
don't run the fans all the time by having them come with the ign. - your car will take longer to warmup and you will wear your fans out 10times faster (ask me how I know)
if you are talking about an aftermarket fan, then you will not be able to control it with the stock relay syst. - aftermarket fans are not made to run at variable speeds like the stock fans
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From: Florida
BOTTLEFEED
I HAVE THE STOCK FANS CENNECTED TO MY AUX OF MY MICROTECH to the relays and I can program the microtech to switch on the fans at whatever temps but I have it connected to the #4 relay, what I want to know is if that would make all 4 relay kick at the same time so I have the high speed as of now I dont know what speed they are on low med or high?
I HAVE THE STOCK FANS CENNECTED TO MY AUX OF MY MICROTECH to the relays and I can program the microtech to switch on the fans at whatever temps but I have it connected to the #4 relay, what I want to know is if that would make all 4 relay kick at the same time so I have the high speed as of now I dont know what speed they are on low med or high?
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