Hello. I live in Saskatoon. It was -35 Celcius yesterday. I moved the fan switch from 3 to 4 on my 1991 Honda Civic SE and now its broken. This is the switch that is OFF-1-2-3-4. It is now permanently OFF. And its cold. lol. Is there a way to manually open the heater vents to 4 until I can afford to replace the whole temperature control unit? By the way, my Civic has 520,000 km and still runs GREAT. Any help would be appreciated. I have a 30-minute commute to work and these temperatures are....not fun. lol.

 

Are you sure that it's the fan switch and not the blower resistor behind the glovebox? Sold those at a rate of 3:1 when it came to heater switches in the winter time in Calgary. Much more common. Much easier to replace too.

 

Hello and thanks for the reply. I am fairly certain its the actual sliding switch. It has been fairly stubborn and sticky for a while and it sounded like it physically broke when I moved it from "3" to "4". Is there a way to manually open the vent to alllow heat until such time as I can replace the temperature control unit? Thank you.

 

While I agree with jhmed on this, you may have actually broke the plastic. I know there is a piece in the engine bay that lets the coolant flow into the heater box. But as far as the fan and the vents, I am unsure. You could probably take the middle console/dash portion out and look at the back of it and rig something to work as a temp fix.

 

Here is the temperature control system. Its the OFF-1-2-3-4 switch that broke. Can I manually adjust a valve to get heat going again? Thank you.

http://www.ebay.com/itm/88-91-Honda-Civic-OEM-A-C-ac-heating-climate-control-temperature-switch-/200997906810?pt=Motors_Car_Truck_Parts_Accessories&hash=item2ecc68a97a

 

That switch connects to a wire that connects to a lever under the glove compartment... that lever connects to a hose on the firewall of your civic... and yes you can slide it by hand.

 

Thank you so much. So the lever is under the glove box?

 

Wait, I'm confused now. It seems like instrument is referring to the hot/cold mixing dial. This is connected to the valve in the engine compartment via mechanical cable.

The fan control switch that MikeSaskatoon is referring to is something entirely different. I'd imagine it's a sliding switch that makes contact with the various points on the blower motor resistor/blower motor circuit.

 

It looks like it's just some sort of sliding switch that runs out to a wiring connector. You might need to do some surgery on the control unit.

A field-expedient fix might involve unplugging the connector and jumping the appropriate pins with the right gauge wire.

Not sure how one would go about permanently fixing this. Good luck.

 

Ok. I have removed the stereo and now have the temperature control unit semi-detached. I have also removed the glove box. I am, however, unable to decipher how to manually switch over from OFF to level "4" (full blast lol). I am certain that there must be a way to manually open the vents all the way without me having to disassembe the temperature control unit..... hopefully. lol. Thank you!

 

"A field-expedient fix might involve unplugging the connector and jumping the appropriate pins with the right gauge wire."

That sounds like a great idea but I would need to defer to somebody who knows about that connector and which pins I would need to jump.

I found this from a service manual online and it shows the pins and connector for the OFF-1-2-3-4 switch....

http://postimg.org/image/9lr35clb7/3867e1d4/

 

So, can I just use some wire and connect pins 1, 3 and 6 which is the option for setting "4"?

 

Give it a try! I don't have the schematic in front of me, but it sure looks like that is what the switch is doing in position 4.

Remember to use thick enough gauge wire so you don't burn or melt or smoke.

-p

 

Thank you. It actually worked. lol. I cannot adjust the setting but the heat goes steady at velocity "4" now and all I had to do was remove part of the dash, pull the pin connector from the back of the cliamte control and run copper wires from the three pin locations identified in the posted diagram. :-) Do you know how totally conventient it is to drive in -36C weather with a heater? lol. I drove one day without a heater and had to drive with the windows down because it was fogging up. lmao.

 

For anyone reading this not wanting to experience the same failure, spray a quick shot of silicone spray into the slider for 1-4 once a year. Keeps it sliding nicely , but remember to disconnect neg cable first and wait twenty minutes before putting any power back to the car.

 

I bet that if you had a 3 position toggle switch you could rewire the switch to high, off and low. Would you consider looking into that? They are probably less than 5 bucks at Radio Shack... Anyway, glad you are not freezing your butt off!

 

That sounds like a great idea, radex7. I may invesigate that next weekend. I will have to research connecting a 6-pin female connector to a 3- (or 4-?) position toggle switch. (Sorry for the delayed response....twas off the grid for a few days.)