Extra wire in harness?

[Mrbill426]

I just received a replacement harness and I see there is a extra wire at one (coil side?) of the ballast connectors.  Can anyone explain?  It's a '72.

[Burdar]

Who's harness is that?  Did they list an early and late harness style?  There could have been a change at some point in the model year.  Did you call the harness manufacture and see what they say?  Maybe send them that picture.

[Mrbill426]

Evans Wiring Harnesses is the mfg and cataloging just says 1972 with 318/340 & electronic ignition w/o air pump.  Says it has some sort of connector for emissions checks but unless I am blind I don't see it.  Not worried about it but...  I will contact them.

My front lighting harness (also for 1972) does not have female bullet plugs to connect to the fender mounted turn signal wires.   I can fix that fairly easy though rather than BS-ing around with returns and getting back who knows what.   Odd thing about those turn signals is when looking around for repops I don't see listings for '72 E-body; only earlier years.   Well it has them and so says the build sheet.

Who's harness is that?  Did they list an early and late harness style?  There could have been a change at some point in the model year.  Did you call the harness manufacture and see what they say?  Maybe send them that picture.

[Chryco Psycho]

the blue wire with white trace should be 12v power switched , the umper feeds the other side of the ballast to the dropped voltage at the ECU , the blue wire with yellow trace will feed 12v to the ECU , the dropped voltage to the ECU , green wire, is not used anymore as the Ecu now uses 4 pins instead of 5 

[Bullitt-]

  I understand the turn signals changed along the way ...
noticed the other day these later model ones which were not available a few years ago
  Not sure which your '72 would use
https://vansauto.com/product/turn-signal-fender-top-73-74-a-b-e-body-73-79-dodge-truck/

70-71  https://vansauto.com/product/turn-signal-fender-top-70-72-69-70-b-70-71-e-body/

[Mrbill426]

So with this new harness I need to be sure and use a 5-pin ECU?  The car had a 5-pin "gold" box which while stored away started leaking a bunch of sticky goop.  Is my old harness made for a 4-pin ECU?  Will either work with the new harness?
Sorry electrical is not a strong point and I am trying to wrap my aging head around this.
Thanks!

the blue wire with white trace should be 12v power switched , the umper feeds the other side of the ballast to the dropped voltage at the ECU , the blue wire with yellow trace will feed 12v to the ECU , the dropped voltage to the ECU , green wire, is not used anymore as the Ecu now uses 4 pins instead of 5

[anlauto]

The extra blue wire could be for an idol stop solenoid or something ? Where does it go ?

[Mrbill426]

Yes mine look like the earlier 70-71 type  with no screws through the tops; held on by studs and long thumb nuts from the bottom.
Thanks!

  I understand the turn signals changed along the way ...
noticed the other day these later model ones which were not available a few years ago
  Not sure which your '72 would use
https://vansauto.com/product/turn-signal-fender-top-73-74-a-b-e-body-73-79-dodge-truck/

70-71  https://vansauto.com/product/turn-signal-fender-top-70-72-69-70-b-70-71-e-body/

[Mrbill426]

Best I can tell so far back to the bulkhead connector.  It's almost like they are married up somewhere under the harness tape.  I have to look again I guess.
It's weird to me that one side of the ballast harness has a single two-slot connector and the other side (with the shunt wire) has two separate connectors; looks sloppy.

The extra blue wire could be for an idol stop solenoid or something ? Where does it go ?

[Burdar]

72 still used the 70-71 style fender mounted turn signals.  73 is when they standardized them to the ones with the visible screw on top.

[Burdar]

I just looked up the M&H harnesses that Year One sells. They list two for 72 E-body.

HU240N 1972 dodge & plymouth, e-body 318 ci. except electronic ignition
HU240NM 1972 dodge & plymouth, e-body 318 ci. with electronic ignition update

Is your car a 340 car or 318? Did it originally have electronic ignition?

So with this new harness I need to be sure and use a 5-pin ECU?  The car had a 5-pin "gold" box which while stored away started leaking a bunch of sticky goop.  Is my old harness made for a 4-pin ECU?  Will either work with the new harness?

Stock ignition boxes were 5 pin and required the 4 prong ballast.  You can use a 4 pin in place of a 5 pin.  Technically you only need to run a 2 prong ballast with the 4 pin ECU but you can use a 4 prong ballast if you want to look stock.  The extra wire doesn't go to anything in the 4 pin ECU.

[Mrbill426]

It is a 1972 with a original (#) 340, factory A/C, and original electronic ignition.  Everything listed on its build sheet was on the car when I bought it except someone swapped out the TQ for a Holley; removed the resonators, and swapped out the original water valve for a aftermarket one.  I am putting it all back the way it was.  Car has been wrecked at least once but again everything matches... all matching VINS where they should be.   I don't know what YO means by update if it came off the line with it unless some 72s came with points and that is for those who ripped them out and installed a ECU later??

I got a reply from Mr Evans who says to run the harness as is but use a 5-pin ECU  (as it had anyway) and of course 4-pin ballast.  He also said my harness "looks like a over the counter dealer replacement harness".  I suppose that is possible; he should know better than I.

I just looked up the M&H harnesses that Year One sells. They list two for 72 E-body.

HU240N 1972 dodge & plymouth, e-body 318 ci. except electronic ignition
HU240NM 1972 dodge & plymouth, e-body 318 ci. with electronic ignition update

Is your car a 340 car or 318? Did it originally have electronic ignition?

So with this new harness I need to be sure and use a 5-pin ECU?  The car had a 5-pin "gold" box which while stored away started leaking a bunch of sticky goop.  Is my old harness made for a 4-pin ECU?  Will either work with the new harness?

Stock ignition boxes were 5 pin and required the 4 prong ballast.  You can use a 4 pin in place of a 5 pin.  Technically you only need to run a 2 prong ballast with the 4 pin ECU but you can use a 4 prong ballast if you want to look stock.  The extra wire doesn't go to anything in the 4 pin ECU.

[Burdar]

The 4 pin ECU is a direct replacement for the 5 pin.  You can still use your 4 prong ballast so it looks original.

I think 318 cars in 72 still used points.  I'm pretty sure all 340s had electronic ignition starting in 71.

[71383bee]

I just looked up the M&H harnesses that Year One sells. They list two for 72 E-body.

HU240N 1972 dodge & plymouth, e-body 318 ci. except electronic ignition
HU240NM 1972 dodge & plymouth, e-body 318 ci. with electronic ignition update

Is your car a 340 car or 318? Did it originally have electronic ignition?

So with this new harness I need to be sure and use a 5-pin ECU?  The car had a 5-pin "gold" box which while stored away started leaking a bunch of sticky goop.  Is my old harness made for a 4-pin ECU?  Will either work with the new harness?

Stock ignition boxes were 5 pin and required the 4 prong ballast.  You can use a 4 pin in place of a 5 pin.  Technically you only need to run a 2 prong ballast with the 4 pin ECU but you can use a 4 prong ballast if you want to look stock.  The extra wire doesn't go to anything in the 4 pin ECU.

That is my understanding as well.  You should be able to run either the 5 pin or 4 pin ECU.  You just can't run a 5 pin ECU with the newer styled ballast resistor and wiring. 

[MOPAR MITCH]

My 72 318 Ralley came with factory electronic ignition and the 5-prong ECU (and 4-prong ballast resistor).

Also, the side light wiring and turn signal wiring all changed in 72 ... 70/71 was different with the wiring ends... I know... I've swapped this out years ago.