wiring harness

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68ddart

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looking for some suggestions..i have a 68 dart 270 car that i have changed to 340 engine and i am working on the factory wiring.i recently replaced the underdash wiring and everything looked good and went right in place ..i purchased a under hood kit and it had been modified for electronic ignition which i have added and everything went in place except the horn and side marker lights which i was going to lengthen. but when i powered up all i got was tail lights and none of the fuses had power..i think my trouble is with the underhood harness which i now think is for a 67 dart . .so far have only found a used harness from a 68 6 cyl dart..will that work? found a after market harness for 170 or i can lay out my old 6 cyl harness that is cut up and try to make it work..any idea or suggestions is appreciated.thanks
 
OK-lets not get crazy yet. Look at your schematic. Power comes from the battery to the starter relay, then I think through the bulkhead connecter, then somehow to ammeter and ignition switch. Lets start by following the flow. Check some of these places and see what we got. Good luck.
 
My suggestion: Lay out yours. A piece of plywood is handy. Murray's suggestion is also good. Print the diagrams from the Dodge service manual.
I can tell you
a. Plymouth '68 A-body is wired different enough from a '67 they can not be directly interchanged. Dodge is probably the same.
b. There's not much difference between a '67 /6 engine harness amd a v-8 harness.
 
Start by going over to MyMopar and downloading the appropriate factory service manuals as well as the aftermarket (2 page) wiring diagrams so that you can compare them. If the bulkhead connector plugs together you likely can re-pin the engine side to get things to match.

Be specific about what you are referring to. You use the word harness, ??whut??

What specific harness? Is this a repop new that was supposed to fit a 68, or what

Is your "other harness' a junkyard one you found?

Be aware that the FACTORY MANUALS ARE WRONG for a few years concerning theyellow start wire and the horn wiring. This is easy to figure out.
 
thanks for the suggestions,i did compare my old cut up harness to the harness that is not working on my car now ,they plug in the same but wires are in different locations on plugs so that means i will need a new harness under hood...my choices now are vanholics at 170.00 non electronic or herbs at 314.00 electronic ignition..the original harness is to cut up ..thanks again....didnt mean to be confusing 67 dart but i dont know any other term for a group of wires under the hood and thanks for the info.
 
i just purchased a complete engine / front light harness that was modified for electronic ignition from year one part number HU202am for 110.00 shipped..i wont beleive it till i see it but seemed to good to be true ,they guaranteed it to be what i needed...if not i will send it back
 
There was a thread on here somewhere, that a member purchased one similar to yours. I think he stated they shipped 2 harness for underhood, but didnt get one for the wiper motor? Just an fyi. Sounds like a good price.
Steve
i just purchased a complete engine / front light harness that was modified for electronic ignition from year one part number HU202am for 110.00 shipped..i wont beleive it till i see it but seemed to good to be true ,they guaranteed it to be what i needed...if not i will send it back
 
that means i will need a new harness under hood....

No it doesn't. You need to "ohm it out" (check continuity) and read the diagrams and figure out the difference. IT IS EASY to release the connector terminals, pull them out and "repin" the harness. You might not be able to "fix" everything that way, you may have to cut/ splice in the harness in one or two circuits.
 
[QUOTE="68ddart, post: 1972251643, member: 27289"t i dont know any other term for a group of wires under the hood and thanks for the info.[/QUOTE]

What I'm getting at is if you want help you need to tell us WHICH harness (es) you have specifically so we can look up the appropriate diagrams. These are not that difficult to fix
 
good suggestion ,but already got new harness coming ..i will have to get better at my questions when asking for help...if the new harness doesnt work i will try swapping the terminals..thanks for the helpful advise..this site has been a great help thru this process..wiring and reading diagrams are not as easy for some of us but i do understand what your saying ,thanks again sorry for the confusion
 
good suggestion ,but already got new harness coming ..i will have to get better at my questions when asking for help...if the new harness doesnt work i will try swapping the terminals..thanks for the helpful advise..this site has been a great help thru this process..wiring and reading diagrams are not as easy for some of us but i do understand what your saying ,thanks again sorry for the confusion


I would certainly recommend you go through the new harness BEFORE installing it and make certain it will work. You don't want to end up with french fried plastic

One easy way to protect when looking for shorts would be this:

Get yourself a stop/ tail "junk" socket and an 1157 bulb. You don't want an LED you want something that draws SOME CURRENT. Another great tool is an old headlamp bulb. You wire the bulb in series with the battery ground, so that if "something else" tries to burn something (short) it will simply light up the lamp

The thing about a stop /tail lamp is you can wire it several ways for testing. Put a pigtail on the lamp ground/ shell, now you have three wires:

LOWEST current: Hook with the two lamp wires, and leave the shell unconnected. This wires the test in series with the two lamp filaments

MORE current: Hook to the shell and the tail wire, which is the smaller wattage filament

MORE YET current: Hook to the shell and the stop wire

MOST current: Hook the two filament wires together, and wire the test to the shell on one terminal and the two connected filaments on the other terminal. This puts both bulb filaments in parallel

I used to use this for charging small ---bike----batteries when all I had was a big 10A charger.
 
wiring and reading diagrams are not as easy for some of us
Diagram wires are labelled. First part is a reference letter and number, such as A or A1. The next segment may be A2. If it connects to something else, it may get a different letter for the subcircuit.
Then it will have the diameter of the wire in American Wire Gage (AWG).
Finally it will have the insulation color. * = stripe of opposing color.
Splice connections are marked with a solid dot.

These two booklets (and slide show) should also help.
1973 Chrysler and Imperial Understanding The Electrical System Service Reference Guide from the Master Technician Service Conference Series Session 310

1973 Chrysler and Imperial Electrical Circuit Troubleshooting from the Master Technician Service Conference Series Session 311

Maybe the most important connections to verify first are the ones that are always hot. That's the wiring from the battery positive to alternator output stud and everything inbetween that doesn't have an off switch.
Lets walk through one example with a '68 Barracuda diagram (probably similar to a '68 Dart).
The battery hot connects at the bulkhead cavities 'J' and then 'P' continues to the alternator. On the passenger compartment side there will be a matching heavy red (12 gage) and heavy black (12 gage) wire in those two locations. (A '67 engine harness would make 'Z' hot! Connecting that to a '68 could be a big oops.)
Also notice the ammeter shows zero, but even so, if the battery is connected it is electrically HOT; as are the feed connections at the headlight switch, a portion of the fuse box, and the alternator output stud.

Charging-diagram68BV+Headlights-A.PNG
 
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Let me give you an example how I would approach this......

Hook your "big" test lamp from battery to ground so it is in series with ground

Hook up the engine bay harness, and make sure all wiring is "safe" from shorts to the vehicle ground.

Start with the "big" circuits, get your fuse link hooked up. Make sure EVERYTHING in the car is "off" door switches "off" (doors closed,), trunk and glove box lamp off, key off, etc,

Your test lamp should NOT light. If it does, stop right there!!! and find out why.

Continue with the "big" circuits........hook up the alternator output wire..........don't worry about harness dress/ layout yet, just hook it up. should have no light at your test lamp

"Rig" a test lamp to ground from the starter relay (yellow) "start" wire. Should go "hot" when you twist the key to "start." Try hooking this up to the start relay at proper place Hook up your neutral safety/ clutch safety switch. With the key twisted, the test lamp should now light "bright."

You can briefly hook your ground up "for real" and test, that the engine cranks.

Hook the test lamp back up

Let's say "down the list" you want to test your water temp gauge and oil sender gauge/ lamp If they are wired wrong, you don't want to fry something if the wire has "straight" 12V somehow. So you want your "big" test lamp in the ground lead again for safety

With the key in "run" both the oil sender and temp sender wires should show some voltage on a meter or light a small test lamp. This is because they go through the gauge "limiter" and will / should not be full 12V. With a test lamp from the temp sender to ground you should get "some" reading on the temp gauge. With a test lamp connected to the oil sender, you should get some reading on the oil gauge or the oil lamp should light "dimly." If this happens, these are checked and you can hook them up or mark them off

Just go on down the list. When you get to your brake warning switch wire, again, a small test lamp from the wire to ground should cause the warning lamp to light dimly, with key in run

When you get to the "blue" ignition run circuit, it should be "hot" ONLY with the key in "run." Should NOT be hot in "start."

And so on, one wire at a time. There just are not that many................
 
sounds like a good way to test everything ,i will let you know how it goes,thanks alot
 
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