KiLLeR2001
10-07-2010, 11:06 PM
Hello again Zilvians. Tired of having your electric fans on as soon as you turn your ignition on? Don't want to wire an aftermarket switch and then figure out where to put it inside your car? Well then come no further! I've been putting this little project off for the longest time, and since winter is approaching I finally decided to get it done!
http://tehl33tsite.com/240sxdd/acswitch/s13hvac.jpg
For those of you who DO NOT have A/C in your car and DO NOT plan on getting A/C in your car anytime soon, this is for you! What this modification does is take the stock HVAC A/C Switch button and makes it toggle your electric fan setup on/off. Yay.
First off, I'm going to assume you already have your electric fans wired up with a relay. If you don't know how to wire up your electric fans you can search the forums as it has been beaten to death many a time.
Note: If you have your Relay [86] switch hooked up to your fuel pump wire, please remove it. This is not the proper way, instead wire it the blue wire that is going to your ACC Relay in the relay box on the driver side (S13). Here is an example:
http://tehl33tsite.com/240sxdd/acswitch/IMAG0100.jpg
The white wire is joined with the blue ACC wire which forwards to the relay (+) switch.
So now lets get into the mod!
First thing you'll want to do is go into your engine bay and look for this plug...
http://tehl33tsite.com/240sxdd/acswitch/IMAG0099.jpg
This plug comes out of the fuse box on the passenger side and originally went into your A/C canister. It has a light green wire and a light green w/ red wire.
Once you locate it, cut the harness off since you won't be needing it. Now take the two wires and join them together with another wire. Once all three wires are twisted together, solder them, and take the one wire and ground it to the chassis. This step is solely for the purpose of making the A/C Switch green light turn on when the switch is pressed. Here is a diagram...
http://tehl33tsite.com/240sxdd/acswitch/dia1.jpg
Next step is the tricky one. We need to connect the negative [85] part of your relay switch to the wire that sends out a negative signal when the A/C switch is pushed down. You will have to remove the glove box, which is 4 easy 10mm bolts. Once you have the glove box down, you need to look for the thermo control amp, its a little black box, can't miss it, shown here...
http://tehl33tsite.com/240sxdd/acswitch/IMAG0101.jpg
Unplug the harness because it serves no purpose being plugged in if you don't have A/C. Now locate the light green wire w/ black stripe (middle wire) and peel back some of the casing. Connect a new wire to this wire and make sure its long enough. This needs to go back to the engine bay where your electric fan relay is. Don't forget to solder it up nicely and tape efficiently.
http://tehl33tsite.com/240sxdd/acswitch/IMAG0102.jpg
Here is the same white wire from the engine bay going into the cabin. You will connect this wire to the [85] spot on your relay, essentially its the negative trigger.
There you go, that's it! Nice and simple. Of course if you have your fans hooked up to a thermal switch this mod is irrelevant but I know a lot of you are running fans always on... So now you have more control of your fans, with a stock appearance.
Good luck! Any questions feel free to ask.
http://tehl33tsite.com/240sxdd/acswitch/s13hvac.jpg
For those of you who DO NOT have A/C in your car and DO NOT plan on getting A/C in your car anytime soon, this is for you! What this modification does is take the stock HVAC A/C Switch button and makes it toggle your electric fan setup on/off. Yay.
First off, I'm going to assume you already have your electric fans wired up with a relay. If you don't know how to wire up your electric fans you can search the forums as it has been beaten to death many a time.
Note: If you have your Relay [86] switch hooked up to your fuel pump wire, please remove it. This is not the proper way, instead wire it the blue wire that is going to your ACC Relay in the relay box on the driver side (S13). Here is an example:
http://tehl33tsite.com/240sxdd/acswitch/IMAG0100.jpg
The white wire is joined with the blue ACC wire which forwards to the relay (+) switch.
So now lets get into the mod!
First thing you'll want to do is go into your engine bay and look for this plug...
http://tehl33tsite.com/240sxdd/acswitch/IMAG0099.jpg
This plug comes out of the fuse box on the passenger side and originally went into your A/C canister. It has a light green wire and a light green w/ red wire.
Once you locate it, cut the harness off since you won't be needing it. Now take the two wires and join them together with another wire. Once all three wires are twisted together, solder them, and take the one wire and ground it to the chassis. This step is solely for the purpose of making the A/C Switch green light turn on when the switch is pressed. Here is a diagram...
http://tehl33tsite.com/240sxdd/acswitch/dia1.jpg
Next step is the tricky one. We need to connect the negative [85] part of your relay switch to the wire that sends out a negative signal when the A/C switch is pushed down. You will have to remove the glove box, which is 4 easy 10mm bolts. Once you have the glove box down, you need to look for the thermo control amp, its a little black box, can't miss it, shown here...
http://tehl33tsite.com/240sxdd/acswitch/IMAG0101.jpg
Unplug the harness because it serves no purpose being plugged in if you don't have A/C. Now locate the light green wire w/ black stripe (middle wire) and peel back some of the casing. Connect a new wire to this wire and make sure its long enough. This needs to go back to the engine bay where your electric fan relay is. Don't forget to solder it up nicely and tape efficiently.
http://tehl33tsite.com/240sxdd/acswitch/IMAG0102.jpg
Here is the same white wire from the engine bay going into the cabin. You will connect this wire to the [85] spot on your relay, essentially its the negative trigger.
There you go, that's it! Nice and simple. Of course if you have your fans hooked up to a thermal switch this mod is irrelevant but I know a lot of you are running fans always on... So now you have more control of your fans, with a stock appearance.
Good luck! Any questions feel free to ask.