How Do I Remove Dash Wiring Harness?

[Henrius]

I finally got the instrument panel out of my 1972 Newport. Many connectors are badly cracked. Fortunately, I found a place in Canada that restores MOPAR wiring harnesses.

Wow, what a job! Never completely removed a wiring harness before. Got it all disconnected from sockets in the cluster. One cable goes to the firewall into the engine compartment on the passenger side to whereabouts unknown. Do I just cut the wire bunch and install a connector for simplicity?

And how do I disconnect the harness power feeds from the fuse block? Do I remove the fused block from the engine compartment power source?

Another question: what are the round connectors called that plug into power buses? I can't seem to find this sort of connector, in order to stay original. The hot wires are always female so they won't short out if they touch the dash metal.

This project is much more complicated than I anticipated. I am labelling connections as best I can, but it will be a miracle to get the harness out, then reconnected once more when it comes back from rebuilding. One thing for sure: all the replacement bulbs will be LED so I never have to replace them!

 

[CBODY67]

In some cases, what you're terming "harness" can really be serveral different harnesses, depending upon what they run/attach to. As in the instrument cluster, a/c, lights, side-to-side for the courtesy light switches and map light, steering column items, plus the main feeds from the inner fuseblock itself.

Consider that at the assembly plant, the instrument panels were put together at "off-line assembly" and then taken to the main assembly line (nearby, typically) as one assembly. The front seats were not there yet so it was walked through the front seat area and bolted to the body structure as an assembly. HVAC was already installed on the firewall. Steering column was not there yet, either. In a modular type of approach.

Hope this might help,
CBODY67

 

[71NewYorkMan]

Do I just cut the wire bunch and install a connector for simplicity?

NO!

Unless your harness is totally degraded (all terminals badly corroded, insulation cracking/crumbling, etc). You are better off repairing. The MOPAR terminals were of the Faston type, which are still available. The terminals can be removed from their housings using appropriate tools. Terminals are readily available, housings are hit or miss.

what are the round connectors called that plug into power buses?

Are you referring to these? Male and female replacements are available in different sizes.

Photos of the specific items you asked about would be helpful.

 

[Ross Wooldridge]

DO NOT cut your harness. Where it goes into the firewall and out to the engine bay is actually quite easily disconnected. You do it from the engine side.

It's called the bulkhead connector. There should be four tabs (two on each side) that click into the edge of the hole in the firewall. Press the two on the same side and the connector should fall into the interior. However, you'll likely have to disconnect up to 3 engine bay harnesses that clip onto that big connector.

Each of those smaller connectors have little arms that clip to the side of the big connector. Using a small screw driver, carefully work those off the big connector's bumps that hold them on.

While it may not look exactly like what's in your car, here is a picture of the big connector that all your dash wires go into. The side you see is the engine bay side, and the wires come into it from the side that is lying on the plastic bag. You depress the two clips to allow it to fall into the interior.

Here's a pic of an engine bay harness connector (again, it may not be exact, but it will give you the idea) - you can see the arms that connect to the little tabs on the sides of the 8 hole connector towers on the big connector - carefully pry them away to free up the little harness in the engine bay and allow it to be removed from the big harness.

I assume you've disconnected the battery while you're doing all this??

 

[Henrius]

NO!

Unless your harness is totally degraded (all terminals badly corroded, insulation cracking/crumbling, etc). You are better off repairing. The MOPAR terminals were of the Faston type, which are still available. The terminals can be removed from their housings using appropriate tools. Terminals are readily available, housings are hit or miss.



Are you referring to these? Male and female replacements are available in different sizes.
View attachment 442542

Well, I had not really planned to remove the wiring. Trouble was, I could not find a source of odd-shaped connectors like the ones that went to the headlight switch or steering wheel harness. So the second option was to remove them completely and let someone refurbish them. Mr. Heaterbox in Canada says they do this.

But removing the harnesses is more work than I imagined.

 

[Henrius]

Sure would be easier to disconnect if the engine were not in place! Gosh, getting to that bulkhead connector is a pain. Guess I will jack the car up and see if I can work on it from underneath. Now I know why the two restoration shops I have approached don't want to work on dash projects! The difference tween my Pinto without A/C and luxury care like the Newport with A/C is like night and day!

 

[CBODY67]

Ever look in the "Standard Parts" section of a Chrysler parts book? I suspect that many of the needed connectors are "out there" in the restoration parts realm of things. Not from normal parts sellers, typically. Probably not ONE "one-stop-shop", though. After all, the people who'll be reburbing you harness have to get the items "somewhere". In any event, it will be easier to do the work with the harness out of the car, period.

Seems like there are several threads in here, from a few years ago, of members restoring their instrument panels and such, with the IPs removed from the car?

Take care,
CBODY67

 

[Henrius]

NO!

Unless your harness is totally degraded (all terminals badly corroded, insulation cracking/crumbling, etc). You are better off repairing. The MOPAR terminals were of the Faston type, which are still available. The terminals can be removed from their housings using appropriate tools. Terminals are readily available, housings are hit or miss.

Thanks for the Faston reference. I went to their website. Individual crimped connectors are available for each wire, but the plastic pieces that hold the connectors in alignment to fit relays, switches, and etc. are what is badly damaged. These seem to be unavailable. I don't know where harness rebuilders get them.

Mr. Heaterbox said MOPAR wiring was prone to excessive resistance and overheating, which ruined the connector bodies.

 

[71NewYorkMan]

the plastic pieces that hold the connectors in alignment to fit relays, switches, and etc. are what is badly damaged

If you can find a donor harness that has better connector housings, you can use those to repair your own. You could always just crimp new terminals on the wires, and then carefully connect them to the proper terminals on the switches (using the detailed references in the FSM). Unfortunately, there are no easy answers for these cars. Even the A, B, and E bodies are hard to find these parts for. If you do try to score a better harness, try to find one from a northern donor. Plastics seem to age better up there.