Almost ready to put dash back in and I cant locate the connector for the fan switch. The switch has 5 pins and the old connector had a 2 and 3 pin plug. I can only locate a 2 pin plug that looks like it would fit. Do I have the wrong connector or am I missing a harness? Also do all 69 a-body have 5 pins on fan switch? I ordered a CSM but it hasnt arrived yet and the one online is very hard to read.
Thanks, Rob

 

Not sure about your connections, but I believe that only the A/C equiped cars came with the 5 prong fan speed switch. I think the 'heat only' cars came with a 3 prong fan speed switch.

 

I went back to my album and looked at my switch. My 69 had two 2 prong plugs for the top and back on the control panel and five wires for the fan speed. See attached pics for the order on the speed switch wiring.

 

Do you have an AC car?
Thanks, Rob

 

Ive noticed that there is a seperate harness for the heater and AC. The AC has been removed from my car but Im starting to think I may need the old harness.
Thanks

 

The AC harness that you have eliminated by removing the AC connects to the Hi speed fan relay, the resistor on the evap box, the hold-in relay, the compressor as well as the fan switch. AC cars have the 5 pin switch although I am not sure how many pins are used for non AC fan switches. There no plugs in the main dash harness that directly connect to the fan switch. There is just a brown main power feed. This 12V feed ties into either the AC harnes or the Heater harness (non ac cars). You need to get a Heater harness for your car and likely a non AC dash control unit too. Beside the fan switch, there is another switch in the control unit that is controlled by the OFF selector. When the selector is in the OFF position, power to the fan switch is disabled. I'm not sure about the 2 wires on the plug you show in your photo without looking at a wiring diagram but I believe the white wire is the ground wire for the dome light circuit. It may connect to the reading light that was an option and located just above the radio because that reading light is also activated when the interior lights come on.

 

Just looked at your photos again. The two wires on the single plug, which are orange and white, connect to the reading light I previously mentioned. The other white wire is part of the dome light ground circuit although I'm not sure what it plus into.

 

Once again thanks for you help, but that isnt want I wanted to hear. If I change to the non AC controls wouldnt I have to change the heater box too, being that mine is vacuum contolled? Before we ripped apart the car the heater controls worked even with the ac removed. I would like to try to put back in the old ac harness. I think I would need the resistor and a relay?
Thanks, Rob

 

Let's start with what you have and don't have so I have a better picture. It sounds like you retained the AC heater box inside the car with the vacuum servos. Did you remove the Evap box under the hood? You can't easily switch over to a non AC heater box because the firewall has a different cut out for AC vs non AC cars. If you want to retain the vacuum function and the AC heater box, you will need to use the AC harness and use the blower relay (easily put back over by the master cylinder), the resistors that would normally go in the exap box and the hold in relay. If the evap box is removed, you'll need to fabricate something to allow you to use the resistor. I posted an article on the hold in relay and how to modify the system if the relay was dead or maybe in your case, just missing. But don't switch the compressor load through the dash control unit as it was not designed for that. Let me know what you have/don't have and what you think.
Brian

 

I would like to retain the ac box and use of the vacuum controls. The evap box, all of the relays and resistor are all gone. It looks like the old .ac harness is still intact. If needed I think fusick sells the resistor. Your help is much appreciated.
Thanks

 

Make sure to put the resistor in a box of some type and make sure the box is vented. The resistor coils need to breathe to keep from getting too hot. If you put the resistor inside the car, you wouldn't need to run any of the compressor or hold in relay wires outside under the hood which would look a little cleaner. Just tape the unused wire ends up so you don't start a barbecue. Good luck.

 

Sounds easy enough. You mentioned a blower relay and a hold in relay. Am I correct that I still need the blower relay but not the hold in relay? Thanks again

 

That's correct. The Hold-in relay is only used to operate the compressor. The blower relay, which mounts near the master cylinder, will receive wires from the AC harness. One of the wires that is in the bundle that goes over to that blower relay will come off of one of the plugs, have a fused connection and the end of that wire connects to the horn relay where it receives 12V from the battery. This relay controls power to the fan for the high speed and the resistor works the slower speeds.

 

I think I have a pretty good understanding now, but I have one last question. If for some reason I cant locate a blower relay should the lower fan speeds still work without that relay?

 

Not sure. My car isn't far enough along where I could unplug my relay to see what happens. I would need to look at a wiring schematic. See if anyone else posts an answer to that question and if not, I'll see if I can look at the schematic on Tuesday.

 

Brian, thanks for all the help. I hope to put dash in this weekend. Probably few more weeks til I put power to the system. I will let you know how it goes.
Thanks, Rob