M&H wiring harnesses (2024)

In the total rebuild of or ‘67 Barracuda convertible (automatic, console car), I looked at the mess the PO had made of the wiring and opted to go with M&H to replace it all.

As I took the old harness out, I labeled every wire (that I could figure out) by the nearest plug. I highly recommend anyone else doing this do the same.

Some of the M&H wires are long, it came with wiring for a tach (which our car does not have), and no wires or connectors are labeled.

I strung up one harness at a time on the wall, compared the old to the new, researched all mystery wires and it went pretty smooth - with some exceptions…

If you do this, take note:
The M&H harness does not include a wire for the NSS - you get to make it and run it yourself. For the Vert, you will need the short harness that goes from back of ammeter to the top switch and on to the rear harness. You will need the dash harness to lead harness for the console and the harness it connects to for reverse and console lights. You will need your heater and control switch harness - have to pull the black-with-white stripe wire from your old harness plug and install the one on the new harness. If you have a courtesy light, you need that harness as well. The cig lighter wire plugs to the old wire, then the new cig lighter wire connects, then at the end the new door jamb light switch plugs in to the old wire.

These are the only things I have noted - hope to get the dash in this week to try it out. Really hoping everything works, no glows, smoke or flames.

On the back of the instrument panel, you see “RED.” That is where the thick red wire from the dash harness connects. That is where the “top” wire on my car was connected.

Where was it connected in yours?

4SPD-
Please remember the original wiring in my car was “abused” by the PO. I connected the wire where they had it… that doesn’t mean it’s the right place.

I will gladly move the wire if there is a better, accurate place to connect it. It would be easy to do now because the dash is not in the car - I really don’t want to screw it up.

Yep there is "red" and "blk" I believe. It was years ago I took it apart I have no idea but didnt I send you factory schematics?

Bobacuda said:

On the back of the instrument panel, you see “RED.” That is where the thick red wire from the dash harness connects. That is where the “top” wire on my car was connected.

Where was it connected in yours?

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4spdragtop said:

Yep there is "red" and "blk" I believe. It was years ago I took it apart I have no idea but didnt I send you factory schematics?

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You sent me schematics, but I thought “Surely the PO did not screw this up.”
Looks like I will be spending time with the schematics again, tomorrow.

OP - you really need to get an original wiring diagram or service manual. Replicating the PO's bad decisions is a disaster waiting to happen. The tap for lighting package is indeed at the cigar lighter. The M&H dash harness is the wiring that comes with all the cars regardless of options. The lighting package was an option, whether you have AC or not determines what the heater subharness looks like, the console was an option that not all cars had.

I agree with 4spragtop that tapping the back of the alternator for top power sounds like a disaster.

By the way, what is the NSS? If it is the neutral safety switch there is a subharness that plugs into the dash harness or the bulkhead connector (depends on year, model and options). If you had a manual shift car there would not be a neutral safety switch so that subharness would be different.

NSS = neutral safety switch. Our ‘67 is an automatic, console car. It has a 904 from a Volare (3 wire trans switch). The ‘67 trans and wiring would be for a single wire trans switch. The M&H harness did not have it. I made the new NSS wire and connected it to the correct wire on the trans switch.

I have the schematics and will dig back in tomorrow morning.

On FABO, from 65Dartman in 2012:
“FYI the wiring goes something like this - HD wire from the ammeter to the switch, to the circuit breaker to the pump. Also from the switch there are 2 more wires controlling up & down - these go back to the pump.”

I did a search and found this same info from several FABO sources - in fact, 4spdragtop was one of the folks in the info trail. In any event, I will schematically confirm tomorrow.

Thanks to all for interest and input.

Bobacuda said:

NSS = neutral safety switch. Our ‘67 is an automatic, console car. It has a 904 from a Volare (3 wire trans switch). The ‘67 trans and wiring would be for a single wire trans switch. The M&H harness did not have it. I made the new NSS wire and connected it to the correct wire on the trans switch.

I have the schematics and will dig back in tomorrow morning.

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You have it correct.
We've discsussed the differences in the FSM and Barracuda wiring diagrams from the actual assemblies. Its in a few different threads so some assembly required.
On some years/models the convertible top was connected with a ring terminal at the ammeter. Presumably the thinking was the top would only be raised or lowered when the car wasn't moving. edit: See assembly drawing C 11.0
The NSS wire was not in the engine harness.

Bobacuda said:

then at the end the new door jamb light switch plugs in to the old wire.

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You'll find a connector for the '67 console lighting about midway between the steering column and the right side. It's at the end of that wire.

Rally dash redo

Ok, I have looked at the schematics in the Barracuda supplemental info and in the 1967 Plymouth service manual. Both show the top switch to the motor, but neither shows how the power gets to the top switch. In addition to that, I have searched FABO for input.

FABO had the most info, and the consensus is that the top switch wire attaches to the “RED” post of the ammeter, as mine was when I pulled the dash out.

Finally, there is no where else on the back of the instrument panel that could accommodate the top wire.

Thanks to everyone for input.

I would use the fuseblock?? I wonder is 68 or 9 is different for the top switch?
I have 69 schematics at home I can check with.
Take a look thru the "convertible forum" on here? Maybe post the question there also?
These dashes arent easy to access so best to address now beforehand.

Bobacuda said:

Ok, I have looked at the schematics in the Barracuda supplemental info and in the 1967 Plymouth service manual. Both show the top switch to the motor, but neither shows how the power gets to the top switch. In addition to that, I have searched FABO for input.

FABO had the most info, and the consensus is that the top switch wire attaches to the “RED” post of the ammeter, as mine was when I pulled the dash out.

Finally, there is no where else on the back of the instrument panel that could accommodate the top wire.

Thanks to everyone for input.

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I checked the entirety of FABO, including the convertible forum - going back to 2012 (Hey, 4spdragtop, you were there).

Concensus - 1967 connects to the “RED” ammeter post. I did not research 1968 or 1969 models.

Lol yep been here a while...lemme chk 68/9 schematics later

Bobacuda said:

I checked the entirety of FABO, including the convertible forum - going back to 2012 (Hey, 4spdragtop, you were there ).

Concensus - 1967 connects to the “RED” ammeter post. I did not research 1968 or 1969 models.

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Bobacuda said:

FABO had the most info, and the consensus is that the top switch wire attaches to the “RED” post of the ammeter, as mine was when I pulled the dash out.

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That's exactly what is shown in the assembly drawing C 11.0

4spdragtop said:

If that what schematics say for 67, then go for it. I wont waste my time with 68/9 stuff.

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Not the schematics. The Assembly drawings like the one I posted above.

Only thing I see hooked to red ammeter is clock connection.
68/9 schematics are available free at
Mymopar.com

Mattax said:

Not the schematics. The Assembly drawings like the one I posted above.

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