C2 Heater Switch

[Doug L.]

Hello everyone,
I've searched the archives and have not found my question or an answer to it.

I'm installing new electrical harness'. My problem is with the dash harness. Everything is connected except 1 brown wire with a plastic shroud that exits the dash bundle at the same point as the wires for the clock. My shop manual indicates that there should be 2 connections to the heater blower switch. One of those connections is a 3-wire group having B/LBL, B/Y, and B/orange, and I have those all in a common plastic connector. The diagram also shows a brown wire connection to the switch so I'm thinking that this is what the last brown wire is for. However there are 2 remaining empty connection posts on the back of the switch. There are 5 connection posts in total, 3 occupied with the single 3-wire connector and 2 (presumably) singles. If I'm on the right track about this being the connection point for the brown wire, to which of the posts does it get connected? What is the remaining post for?

Thanks in advance for any help.
Doug

[Alan D.]

Re: C2 Heater Switch

Doug,
First I will assume you are using the wiring diagram of the 64 Shop Manual, supplement (Some AIM diagrams in the past were really 65's)

The 64 Manual, page 12-9, shows a total of 5 wires. The three conductor connector holds 4 of those wires, 2 - 14B/O; 1 - 14B/Y; 1- 14B/LBL, so that uses 4 of the 5 wires. The brown is in its own single connector & believe its the 12Vdc main power. And that's it!
The brown is on the opposite side of the 3 contact connector. The metal shaft splits the unit in center thus defining a side. The single male connector coming out of switch is just offset a little from center towards the 14B/LBL connect of the 3 contact connector.

I can not see another male connector exiting from the switch since it would be located above & mirror just will not work.
Would take a guess that the other connector is something to do with the AC option.
Do have original harness out so if a picture would ask.

[Doug L.]

Re: C2 Heater Switch

Hi Alan,
Yes, I am using the 1964 suppliment and looking at page 12-9.

The switch has 5 male pins on the back surrounding the cable that also exits from the back of the switch. The way the switch is mounted in the console has the pins oriented from ~8 o'clock clockwise thru 12 o'clock to 5 o'clock. There is a larger area without pins between pins at the bottom, between 5 and 7 o'clock.

The connector from the bundle (source Lectric Ltd) has 4 wires in it (my error in the first post as I was counting the 2 black with pink trace wires as one since they are in the same junction within the connector. The connector encompasses only 3 of the pins when it is installed on the switch. The pins it connects to are at 12, 3 and 5 o'clock. That leaves 2 pins at 11 and 8 o'clock unaccounted for.

I have 1 brown wire with an installed plastic connector that is not yet connected to anything. The manual shows 1 brown lead to the switch in addition to the 4 mentioned above. The 4 in the connector (B/LBL, B/Y, and 2 B/Or) go to the resistor. From there I am kind of lost in trying to figure out the circuitry.

From a process of elimination I think the brown wire must connect to one of the 2 empty pins on the heater switch, but I don't know which one or what the other is for. Trust me, my switch has 5 pins. No question about that.
Doug

[Dan H.]

Re: C2 Heater Switch

Doug, sounds like the wire may be for rear blower motor on a Coupe, it shuts down when heater is turned on to save the heat. Your wiring harness may have this as an extra for Coupes, not verts.
Dan

[Doug L.]

Re: C2 Heater Switch

Hi Dan,
I'm still confused. I just looked thru the 64 suppliment. There is nothing in the wiring schematics that I can find that mentions the blower in the rear of a coupe. The rear exhaust blower is mentioned in section 13 and described in more detail in section 1, but section 1 seems to indicate that the control of the heater-exhaust fan are internally controlled and not related to the heater switch I'm talking about.

There is a drawing, section 13 fig. 1 that shows the switch I am talking about. That drawing shows 4 pins on the back of the switch, with 3 served by a 3-wire (actually 4-wire. See the above clarification) connector and 1 served by a 1-wire connector. What I take from this is that the switch in my car is not correct in that it has 5 pins instead of 4.

Will it work? I guess I'll find out by connecting to one of the 2 pins and hoping I don't start a fire. I'm going to pick the lowest of the 2 empty pins because that's what the drawing seems to indicate to me. Does anyone have a coupe and knows if the heater switch for a coupe has 5 pins?

Doug

[Alan D.]

Re: C2 Heater Switch

Doug,
"Trust me, my switch has 5 pin" and mine probably does also, just can not see it.
I would say at 8:00 position for the brown.

However the colors bother me a little so I added the picture. Mine has the 14B/LBL where yours is listed as B/O (5:00) My 14B/Y is just like yours, ie at 3:00 The double 14B/O is at 1:00 just like your double B/P Now the repo may be just fine however the colors may be off. So long as the wire goes to correct location the color has no meaning.
Added an edit since I bet next question is just where do those wires go???
At least three seem to go to resistor which controls the blower speed. The other 14B/0 goes back to fuse block. So if your colors line up as my harness, but just have a different then all SB fine.

[Michael M.]

Re: C2 Heater Switch

I think Dan is right. I think it is the power supply wire that connects to a brown wire that is in the rear body harness that comes up from the rear. It would be safer to not connect to anything and see what happens. Mike

[John H.]

Re: C2 Heater Switch

Doug -

Part of the problem is that all of the '64 wiring diagrams were wrong (they omitted the brown power feed wire from the heater blower switch to the rear ventilation blower); they were corrected for '65, which shows that feed wire (coupe only) and the additional (5th) spade terminal on the switch it connects to.

The heater blower switch has a separate (5th) spade terminal for the rear blower feed wire; it's only "hot" when the switch is in the "off" position, and it's "dead" when the switch is in lo, med, or hi position, so the rear ventilation blower won't work with the heater blower going.

[Doug L.]

Re: C2 Heater Switch

Thanks all. What John says makes sense and Alan suggested more or less the same in an e-mail.

I did make a mistake on my little sketch. The wire I show as "B/O" (black with orange trace) is really black with light blue trace. I was working on 2 problems and got them mixed up.

This morning I got under the dash and used an ohm meter, as suggested by Alan, to check conductivity between the terminals on the back of the switch. I got no readings between the 8:00 and 10:00 posts regardless of the "heat" knob being in or out. I also obtained no conductivity between either the 8:00 or 10:00 posts and any of the other three posts, also regardless of knob position/rotation. My guess now is that either the switch is defective or my logic is. I have connected the brown conductor to the 8:00 post. Nothing is connected to the 10:00 post. The 3-wire connector is connected to the 3 posts at 12:00 2:00 and 5:00. When I get the body back on the frame and can get power to the system I'll post the results.

Thanks for all of your suggestions.
Doug

[Dan H.]

Re: C2 Heater Switch

Doug, the NCRS Store 1953 to 1972 wiring diagram book is quite useful and shows the 64 wiring to the rear fan etc.
Dan

[Doug L.]

Re: C2 Heater Switch

Hi Dan,
I don't have a rear fan. My car is a roadster. That's one reason why I'm having a hard time. I have the wiring diagrams in both the full '63 shop manual and the '64 suppliment. Both show 1 brown wire plus the 3-pin connector to the heater switch. So you would think there should be 4 connection points, but I have 5. I have found no diagrams of the switch itself except in the AIM and that seems to be the switch for the coupe.

I have no way to know if someone changed my switch to a coupe switch or if there is only 1 switch for both coupe and roadster where you use 5 pins for coupes and 4 of 5 for roadsters. If the latter, I find nothing to indicate to which of the 2 open pins I should connect the single brown wire.
Doug

[Michael M.]

Re: C2 Heater Switch

switches are the same for coupe and roadster.