Opening up my dash - found a few mystery connectors

[GrantOv]

Started my winter project of opening my dash to replace/fix electrical items. Many questions - Let's start with some mystery connectors that aren't currently connected to anything.

#1, 2, 3 - these connectors are by the accelerator and under the center lower bezel. Not sure what they were meant to connect to as they weren't connected when I removed things.
#4 - this unused connector is scene through the windshield looking down just above the glovebox area
#5 - this unused connector is hanging down through the glovebox area
#6 - I'm wondering about these blue filters on the inside of the instrument cluster. I was surprised to see them. I was thinking of changing out my cluster lights to LED green but if theses filters are meant to show blue then this plan isn't going to work.
#7 - I broke unfortunately the fuel guage electrical mounting posts in disassembly - any suggestions on where to buy or get it repaired? Does Rocketman do this also? (I need my Tach repaired so I'll be sending this over!)

I forgot to mention a few things - this is in a Mustang Mach1 1972. It had the radio removed so perhaps one of the first few connectors are for the radio?

What are your thoughts? Any ideas?
Thanks in advance!
Grant

 

[Doug's 73 Mach1]

1, 2, & 3 would likely be 1) clock feed for full console, 2) radio feed, 3) Ac/heater control back light
4 could be the connector for the 3 gages oil, amp, temp
5 likely a buzzer connection (key in ignition, and or headlights on warning ) perhaps seat belt buzzer
6 These blue lenses cause the instrument background lights to give a somewhat blue look glow when the parking/ headlights are on at night. Can be seen better at night than daytime.

Hope this is helpful

 

[Moderator73]

1, 2, & 3 would likely be 1) clock feed for full console, 2) radio feed, 3) Ac/heater control back light
4 could be the connector for the 3 gages oil, amp, temp
5 likely a buzzer connection (key in ignition, and or headlights on warning ) perhaps seat belt buzzer
6 These blue lenses cause the instrument background lights to give a somewhat blue look glow when the parking/ headlights are on at night. Can be seen better at night than daytime.

Hope this is helpful

Doug is right on with his help on this. Only thing I would correct is on #4. That is showing the main dash harness feed connector (C-702) that connects to harness 13B712. This connector feeds the following four functions:

ckt 14 - Headlamp on - warning relay​

ckt 158 - Key warning switch to buzzer​

ckt 159 - Door Jamb switch to buzzer​

ckt 162 - Emergency Brake light to Emergency Brake switch​

​

As for #5, Doug is right that it is for the Key in Ignition or Headlights on warning buzzer when the door is open. It's not for the seat belt buzzer that's a second buzzer that looks just like it.

Yeah, on #7 definitely talk with Rockman on what your options are.

Good luck with your winter project.

Bob

 

[NOT A T5]

Didn't know Rocketman plays as Rockman in a band!

 

[GrantOv]

Thank you very much for your insight! very helpful!

 

[GrantOv]

I'll have to look closely when I get back to my car but I don't remember seeing a light on the HVAC control. or maybe mine was replaced some time ago with one without a back light? Enclosed is a picture of a top view. Just the pneumatic connector and main connector on the left side.

Or did you mean the #3 to connect to the infamous Map Light power?

 

[Moderator73]

Your selector controls has the opening for the illumination light. Here’s a picture of mine. In my picture you can see that I cut off the connector that goes into your #3 connector. But the pictures show how the bulb mounts into the controller.

I used my missing connector to splice into a new Classic Auto Air system Heater control I’m installing to feed its illumination bulbs. Hope this help.
Bob

 

[GrantOv]

ahhh - my light socket is totally absent Thanks much for the clear pics!

 

[GrantOv]

I'm still working at removing and documenting my dash wiring for refurbishment. I see these 3 on the LH side - 2 of them go to another portion of the harness (A and C) and the third (green - B) was unconnected? Any thoughts on where these go to?

I have 2 wires that are holding me back from disconnecting this harness completely. D and E. I assume these are for the steering column hazard switch but is there by chance a connector that is tucked in there that I can disconnect? I can't seem to put my eyes on it.

Also - I need to connect up an Always On power for my radio memory (USA-740 Custom Autosound). Is there a recommended wire to tap into this low power connection? I plan on using the accessory fuse option for the main power for the radio.

Thanks, Grant

 

[Moderator73]

Hey Grant...hope you're staying warm man. Here's some help for you

A - is Connector C-610 contains ckts#, and wire colors:
#9 LG-O, Left Hand rear tail stop & turn signals
#53 BK-LB, Courtesy Lamp/Door Jamb switch

B - is Connector C-1204 (on a 73, but on a 72 I think it's called C-25 because you only have one pin vs a 73 which has three pins) For Speed control and emissions system. You said it was disconnected already and it goes another harness on your firewall. Once you pull your dash you'll see this small harness goes to an EGR Module mounted on firewall above your heater box.
#57 BK, Ground
#934 T-W, Emission Speed Sensor to Modular Control

C - is Connector C-404
#29 Y-W, Fuel Sender level to Gauge
#5 O-LB, RH Rear Tail Stop & TS
#14 BR, LH Rear Tail Stop & TS
#140 BK-PK, Backup Lamps

D & E - you are right it's for the 4-way Emergency Flasher & that is connector C-603. It'll come out with dash so long as you disconnected the two big harnesses coming out of the steering column. These D&E wires are part of the main under dash harness.
D = Ckt#10 LG-RH, Stop Light Feed
E = Ckt#385 W-RH, Flasher to Emerg Warning Switch

Hope this helps,
Bob

 

[Moderator73]

Your question on "recommended" wire taps for after market radios I'm sure you'll get a lot of different ideas. I'm no expert that's for sure, but here's what I did, because I had my dash out, and my project also involved installing a RetroSound aftermarket radio. With the dash out, the wiring was much easier to access. My thinking was to use the factory connector C-501 for my 12 volt "Switched" connection. I just used a single bullet male connector to insert into the power feed side of this connector. C-501 has wire #296, White-Pink Stripe that is a fused accessory power feed. The other side is wire #19, Light Blue-Red stripe that is for Instrument Panel Lamps. So in my set up, this side of the connector is not used.

In my picture you'll see the Orange line pointing to this connector where I ran my radios red 12V switched power feed.

Now for the constant 12v power source, I used a #37 ckt yellow wire above the glove box relay panel. I spliced another yellow wire on feed line going into the Circuit Breaker Assy for the Stop Lights on this relay panel. My thinking was this was well out of the way of where all the jammed up wires are around the headlight switch and I thought it might look/work better. Just my thinking. In my picture, this is the Green line pointing to this splice for my yellow constant 12V feed to the radio. Oh, and incase you're asking why I tapped on the feed side of the circuit breaker versus the load side...my RetroSound radio had a Fuse on the 12V constant feed line as part of it's supplied aftermarket harness.

 

[GrantOv]

Hey Bob, thanks for the tips and pictures. I'll dig in there more tomorrow because actually it is too Warm for snowmobiling which is a let down this time of year.

I had a logistics question - how much did you leave open in order to connect everything back up when you finished your dash. Could you reach everything you needed to through the main speedo cluster and glove compartment?

Grant

 

[GrantOv]

Hey Grant...hope you're staying warm man. Here's some help for you

A - is Connector C-610 contains ckts#, and wire colors:
#9 LG-O, Left Hand rear tail stop & turn signals
#53 BK-LB, Courtesy Lamp/Door Jamb switch

B - is Connector C-1204 (on a 73, but on a 72 I think it's called C-25 because you only have one pin vs a 73 which has three pins) For Speed control and emissions system. You said it was disconnected already and it goes another harness on your firewall. Once you pull your dash you'll see this small harness goes to an EGR Module mounted on firewall above your heater box.
#57 BK, Ground
#934 T-W, Emission Speed Sensor to Modular Control

C - is Connector C-404
#29 Y-W, Fuel Sender level to Gauge
#5 O-LB, RH Rear Tail Stop & TS
#14 BR, LH Rear Tail Stop & TS
#140 BK-PK, Backup Lamps

D & E - you are right it's for the 4-way Emergency Flasher & that is connector C-603. It'll come out with dash so long as you disconnected the two big harnesses coming out of the steering column. These D&E wires are part of the main under dash harness.
D = Ckt#10 LG-RH, Stop Light Feed
E = Ckt#385 W-RH, Flasher to Emerg Warning Switch

Hope this helps,
Bob

Hey Bob, on the B connector. There one exactly like it on the RH side also. I don't see another connector that may go to it. My guess was that it originally went to the seatbelt switch since there was one on each side.

 

[Moderator73]

Hey Bob, thanks for the tips and pictures. I'll dig in there more tomorrow because actually it is too Warm for snowmobiling which is a let down this time of year.

I had a logistics question - how much did you leave open in order to connect everything back up when you finished your dash. Could you reach everything you needed to through the main speedo cluster and glove compartment?

Grant

Couple of things. First, I haven’t yet reinstalled my dash so can’t say for sure what it will take but that’s because I’m putting in an aftermarket heater box (Classic Auto Air) and the ductwork from the dash and defrost is going to need space to run and attach with the zip ties. That’s my biggest issue for access.

Second, all my wires are connected up now with very few exceptions. The three at the base of the steering column need to be connected which I think will be easy with dash installed (fuse box, ignition switch and turn signal harness). The other connector for my instrument cluster printed circuit board I’ve not yet plugged in just because I don’t want to have to unplug and reconnect any more than necessary. I’m not sure if I’ll need the cluster loose to reconnect the speedometer cable? With the steering column wires disconnected I think I’ll be able to connect the speed o cable with the cluster installed. Other than these wires, the only others are on the ends of the dash that go to the kick panel areas.

In your case you’ll need to reconnect your hvac wires and vacuum lines so you might need to open up your center dash? I’m thinking that with the refurbished dash a couple inches from mounting you’ll be able to reconnect those with the slack?

Sorry I don’t have more on this. Perhaps others can help out better.

 

[Moderator73]

Hey Bob, on the B connector. There one exactly like it on the RH side also. I don't see another connector that may go to it. My guess was that it originally went to the seatbelt switch since there was one on each side.

Not sure what connector you are referring to on the right hand side. Can you show a picture of the one you’re asking about? The seatback/belts connectors are very different from your “B” connectors.

 

[GrantOv]

Thanks - I appreciate the insight. I agree there may be some leeway when the dash is in place but not fastened down fully. Here are a few pictures - first off, I took inspiration and created a 'dash stand'. I think it was a great idea and it didn't take long to pull together.

First two pics show the right and left connectors in the lower front quarter panels. Both sides have the single pin green type "B" that I'm not sure what they are used for.

The center picture shows my dash stand with a center piece circled. This is behind the radio/heater selector bezel. The last two pictures don't show it well but its quite warped. If you know what this is called perhaps I could find a replacement.

Grant