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dalinxz
08-08-2007, 05:49 PM
ok well the overheating problem has persisted so I was wondering, sorry if it's been covered but I removed the AC system, condensor and compressor, and I want to know if there's a way to use the AC button to turn on both fans, it's not turning them on automatically right now, I'm guessing that's because I removed the compressor.

russiankid
08-08-2007, 05:58 PM
ok well the overheating problem has persisted so I was wondering, sorry if it's been covered but I removed the AC system, condensor and compressor, and I want to know if there's a way to use the AC button to turn on both fans, it's not turning them on automatically right now, I'm guessing that's because I removed the compressor.
If you don't have the A/C in the car then don't worry about it. The fans will come on when the temperature reaches a certain point. You have a thermosensor at the bottom of your radiator that sends a signal to a control box when the temp is high to turn the fans on.

dalinxz
08-08-2007, 06:25 PM
ya that's the problem it's already been discussed in another post but the sensor doesn't turn on until it's too late. and I've changed it 3 times all stock ones so it's not it.

LX-incredible
08-08-2007, 10:26 PM
Do the fans turn on at all? If you want the fans to come on with the AC button, you will need to run a jumper wire between the contacts of the pressure sensor. You will need the blower turned on for the button to send current, or you will need to bypass the blower switch. I would check the fuses and try jumping the relay contacts first, to make sure that the fans work.

What submodel are you? LX-i here had a fan timer under the passenger seat. The box is black and to the left. There are 3 diodes inside that are VERY prone to burning out. When these go, the smaller condenser fan will not turn on with either the AC, the thermo switch on the radiator, the timed control, or at all. For those of you that are saying it is normal for just the main fan to be on, you are wrong and likely have a toasted diode. Pop the cover off of the box and have a look. Both fans should run in unison, except when the engine is off and the timer runs the smaller one.

LX-incredible
08-08-2007, 10:44 PM
Test the fans, if they work you can cross the wiring to the fans and fan motors off the list:

That's strange, it should run for longer than that. You can test the fans by running them direct. First remove your under-hood fuse box cover:
http://img163.imageshack.us/img163/3526/overviewft1.th.jpg (http://img163.imageshack.us/my.php?image=overviewft1.jpg)
The second relay from the left is the main cooling fan relay, the round metal relay to the right is the auxiliary relay.
Cut two wires 6-8" long and strip both ends. To test the main cooling fan insert each wire in the two contacts closest to the passenger fender like this:
http://img163.imageshack.us/img163/1885/maincoolingrv8.th.jpg (http://img163.imageshack.us/my.php?image=maincoolingrv8.jpg)
For the hell of it you can also test the auxiliary fan. Insert the two wires in the contacts closest to the firewall like this:
http://img258.imageshack.us/img258/3640/auxcoolingwn4.th.jpg (http://img258.imageshack.us/my.php?image=auxcoolingwn4.jpg)
*Make sure you don't let the wires touch anything, battery voltage is present.
*Check your contacts before connecting the wires.
When the two wires are touched together in the main fan relay slot, the main fan should come on and run for as long as you hold them together. When you touch the auxiliary wires together, the auxiliary fan will come on. If either of the fans don't come on, or run sporadically, the motors need to be replaced/rebuilt
Hope this helps...good luck.

dalinxz
08-08-2007, 10:49 PM
its a DX carbed but the fans do work, when they work they do work in unison(both work together). it comes on too late or not on time until it's overheating and the guage doesn't change so I want to wire the fans so that I can activate them at will so that when its really hot I can have them running, it's only a problem in hot hot weather when your sitting at idle for too long!

LX-incredible
08-08-2007, 11:32 PM
Try jumping the contacts on the plug for the thermo switch, on the bottom of the radiator. Both should come on. What it really sounds like is a bad thermostat. If it is only flowing a trickle, the radiator will cool it down before it gets to the switch.

Blkblurr
08-09-2007, 08:27 AM
Sounds like you may have a plugged radiator. Have you tried flushing it?

Blkblurr
08-09-2007, 08:30 AM
the two wires that went to the compressor clutch could be used to power the second fan. Yo ujust need to connect them correctly with respect to positive and common. If you connnect the two fans together as someone suggested you may blow the fuse powering the first fan.

dalinxz
08-09-2007, 01:18 PM
the radiator is fine it was flushed and I changed it so that can be ruled out as can the thermostat. How would I wire the a/c to the aux fan?

LX-incredible
08-09-2007, 01:45 PM
Feel the top and bottom hoses. If there is a great difference in temperature something may not be flowing right. I have pulled water pumps on these engines where the fins had rusted away into nubs. Running the fans continuous may only mask your problem, by super cooling the small amount of water going into the engine. Jump the contacts of the plug on the bottom of the radiator. If the fans come on, your problem is either with the flow of the coolant or with the sensor. You can connect a switch between the plug's contacts and run some wire, that would the best way. Make sure that it can be easily undone, for I doubt it will permanently fix your problem.

dalinxz
08-09-2007, 02:49 PM
just tested the jumper method, fans are fine, both of them work perfect. Water flow is fine as well as the radiator, and thermostat. The sensor may or may not be the issue I have no clue. I just want to find out how to wire the AC switch to turn on the fans, other than that it's all good thanks.

dalinxz
08-09-2007, 02:50 PM
btw I dont have the sub cooling fan relay, when I jumper the main fan relay both of them turn on.

dlr1989
08-09-2007, 02:51 PM
I know you are wanting to rig a switch to turn on the fans when you want them on. Unfortunately that is only addressing a symptom. Kind of like putting a band aid on a compound bone fracture. The band aid will at best just stop the bleeding for a very short while, while the bone pokes through the skin somewhere else. In reality you need to find and fix the real cooling system problem, at least if you want the car to last you a while.

It sounds to me like you are not getting enough coolant flowing through the system. You changed the radiator and the thermostat. I assume that you bled the air out of the cooling system after those changes using the bleed valve on the thermostat housing, right? As has been previously suggested, what about the water pump, is it new too or is it original equipment? Perhaps a good professional cooling system flush at a good radiator shop (not the Honda dealer) would be in order. A good radiator shop will do a more through job than you can hope to do in your own driveway.

Oldblueaccord
08-09-2007, 06:59 PM
the radiator is fine it was flushed and I changed it so that can be ruled out as can the thermostat. How would I wire the a/c to the aux fan?

Just pressin the ac button the ac fan will come on even if the ac is out.I just pull the ac fuse out. You will have to have the fan on the first speed of course just like if you were running ac.

wp

dalinxz
08-09-2007, 07:58 PM
I'm going to have to check the thermostat again I hope its good; again the flush is already done on both the radiator and the aluminum head. I'm beginning to think it might be the thermostat again but that will have to wait for a week so in the mean time I would rather wire something up. btw I just checked there is no AC fuse under the dash or the hood.

LX-incredible
08-09-2007, 08:08 PM
Just pressin the ac button the ac fan will come on even if the ac is out.I just pull the ac fuse out. You will have to have the fan on the first speed of course just like if you were running ac.
wp
I recall there needing to be a sufficient amount of refrigerant for the pressure switch to let the compressor or the fans come on when the AC button is pushed. Is your system currently charged? The pressure switch can always be bypassed if one were to go this route.

LX-incredible
08-09-2007, 08:21 PM
I'm going to have to check the thermostat again I hope its good; again the flush is already done on both the radiator and the aluminum head. I'm beginning to think it might be the thermostat again but that will have to wait for a week so in the mean time I would rather wire something up. btw I just checked there is no AC fuse under the dash or the hood.
I would just get a honda thermostat. I haven't had good luck with the aftermarkets. The stamped fins on our water pumps will rust off if someone was running a mostly or all water mixture before you. I would get a GMB or Bosch, they have cast impellers and won't rust off as quickly. They go for about $25 here.

dalinxz
08-10-2007, 09:12 AM
btw the compressor and condensor have been removed so there i no pressure within the system. and I will try a new thermostat but I would still like to know how to hardwire the switch?

LX-incredible
08-10-2007, 02:14 PM
The posts above tell you how to run the fans using the ac switch. The pressure switch will need to be bypassed and the blower switch will either need to be turned on or bypassed, in order for the ac button to work the fans when pressed. Another way would be to run two wires and a switch from the thermo switch plug, near the bottom of the radiator.

If the thermostat doesn't do it, I would check the water pump. It seems very unlikely that 3 thermo switches didn't work, when the wiring to them is good. I wouldn't be rigging shit like this, especially when it comes to the cooling system.