What fits ???????

[billfury]

Hello all.Well I started the resto on my 72 charger and found that the bulk head is melted on some of the terminals.I wanted to know if all 71-74 b-body wiring harness fit for under the dash,or if anyone has a mint one for sale?I have a rally ,no tach.Thanks.
Billfury

[Chryco Psycho]

different year harnesses had the wires in different positions so just plugging it in may not make everything work , also options changed & the main harness had differtent provisions for things like AC ,cruise etc so depending what your car has could change which harness you need

[billfury]

So 71-4 are different,even if they have the same option?
Billfury

[Nacho-RT74]

 71/73 wiring are basically the same, with just some wires turned around. So if you find any 71/73 wiring just have to be sure about matchs bulkhead terminals with engine bay plugs wires.

One example it could be the windshield washer motor wire. On 71/72 this wire I think is on engine harnnes since whaser reservoir is on passenger side, and 73 ( same as 74 ) has the washer located on driver side, so wire is on headlights harness.

Mostly of options are on separated harness, like A/C harness what is linked with underdash  harness on 4 points... with a black wire coming from underdash harness and inserted on one of the A/C control switch plug cavities, and one green wire coming from A/C harness and plugged on the the accesories source coming from underdash harness. Same about two wires ( green and blue ) what feeds the clutch and blower, that are using two cavities of bulkhead... so if you unjoin this 4 wires you get two separate harnesses.

If you have heater instead A/C, only linked point is the black wire.

You can install a non A/C electrical system on an A/C car just adding or removing the extra harnesses from one to another.

Another difference is 71 wiper washer motor swicth plug from the rest. 71 switch is BIGGER and harnesses does it have 2 plugs to conect on to this switch. 72 and laters switches are smaller and just one plug is used on harness. However, wires are exactly teh same, same colors and same gauge, so if you get a 71 harness to use on your 72 cluster/swicth, you have just to interchange the palstic plug from one to another. ( or chage your wiper switch for a 71 kind LOL )

Rest of options are easier, these were the "harder" example.

so, we can say 71/73 wiring are interchangeable... YES, keeping in mind what you have to do.

Standart clusters Harnesses are also completelly different from Rallyes ones.

Now about tach and/or clock Rallye clusters beside the basic Rallye cluster setup...  Clock harnesses are EXACTLY the same harness than the regular Rallye without clock, The wire taht feeds teh clock comes from ammeter stud and si already attached on back of cluster. Tach ones are different just by ONE wire that is coming from engine bay and ANOTHER wire that si feeded by accesories source, easy to add or remove.

74 wiring harnes is THE ONLY COMPLETELLY DIFFERENT harness because the interlock system. Is easy to modify if you untape and remove the extra wiring inside and turn around the bulhead terminals.


NOW JUMPING ONE STEP AHEAD TO YOUR QUESTION SAVING FROM A FUTURE PROBLEM AND A NEW MELTING

About the melted terminals... I bet are the ones coming from ammeter to starter relay stud ( fuse link ) and the one to alt stud. Is a very tipical Mopar fail.

There is two ways to save from this... one is the one exposed on this website what I don't like becsue some of the stuff they say there is not completely true, the only complete true is that works BUT JUST BECASUE THEY ELIMINATE THE TERMINALS what are the weakest point on the net.
http://www.madelectrical.com/electricaltech/amp-gauges.shtml.

The other one is what MaMopar made ( exposed on attached pic ). Just run parallel heavier wires from engne bay sources up to ammeter throught firewall when cars got more than 60 amps alt, mostly used on tow packaged cars. These heavier wires are able to drive all the extra load added on cars.

I like ammeters, they are more accurate gauge to read charging system conditions.

The fail REALLY about this is that low outputs and low idle charge alts used on mostly of our cars from fact made to work constantly at high output when press gas pedal to keep battery charging beside also keep working the car... the low charge power at iddle is what makes frequently full charge read when you press gas pedal. This makes constant high peaks by long periods of time on charge system that overloads the system. This is the moment when melting happens ( helped by the weak terminals joined with dust and rust ).

Beside the parallel wires of course I got a lates 70s Mopar stock alt that beside charge at iddle, is able to drive more output ( around 80/90 amps ) with this kind of outpup charge and also the constant charge at iddle you get the best average charging system and best charge performance that keeps an average low or medium load on wiring and terminals... no more peaks it means no more overload, and no melt. I did it and I FULL HAPPY.

[billfury]

Nacho,once again you helped me out.I'm printing this and putting it in my charger folder.I'm looking to buy a 71 charger parts car next week.I'm hoping the harness is all good.Should be,the car was t-bone 20 years ago on the pass side and was all # matching from orig owner.What a shame,car looks to be gunmetal w/houndstooth int.Did I say that right?Thanks again.
Billfury

[Ghoste]

What year did they start with the parallel wiring Nacho?

[Nacho-RT74]

I don't know... Diagram is 71.

[Ghoste]

That must be the year then because I can't find anything similar in the 70 fsm.