Imperial Wiring Problems and Repairs

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What is Litz wire (used on Electroluminescent dashes) - by Frank:

"Litz" wire is needed to re-connect the flexible electrical contact that causes the needle to light.  It is a special type of wire used for winding electronic chokes and such.  It was found that in some applications, the electrons travel only on the surface of the wire. Thus Litz wire is actually multiple strands of wire that provides a heck of a lot of surface area. This stuff is not generally available, (you can't get it at Radio Shack) but is used by component manufacturers. I suppose that you could also get a small RF choke (even pull one from an old TV or radio) and carefully unwind the wire from the device. I think that a choke rated at just a few micro-henries should provide you with the type of wire that you are looking to get, but my memory is really hazy on this.

What is a wiring harness - by Tony:

In an Imperial's case, a wiring-harness is a bundle of electrical wires, taped together with black tape so that they are easy to route from place to place inside the car. On the '60-63 Imperials, the side-window, power-vent-window, and power-door-lock harness (if the car has all three of those items installed) runs from each door through the black-rubber tube to the car-body, over and around the base of the windshield behind the dash, and connects to the circuit-breaker near the driver's left knee.  Some of the harnesses are separate, so there actually may be three or more different harnesses behind the dash of your Imperial.

Where to get wiring diagrams:

The best place to locate a wiring diagram is in your factory service manual.  If you just need the diagram, try Rhode Island Wiring Service:

567 Liberty Lane., Box 434

W. Kingston, RI., 02892

Tel: 401-789-1955 Fax: 401-783-0091

Tip from 4-toes:

Just a general note about automotive wiring. Many of the lights, relays, etc. use switched negatives. What this means is that the positive power comes thru the fuse, goes to the device and then the operating switch is in the negative (ground) side. This means you can have a good fuse and the circuit still will not work. You need a good ground. Light bulbs are usually grounded through their sockets. They don't have switched grounds in this case but the socket must make good ground contact. Dome lights, switched from a door switch usually switch the ground. Many window motors are grounded through their case. In old cars there is often some corrosion at the ground points. This is a common problem with inoperable circuits.

Question from Dave:

I hope that some one out there can help on this. When replacing old wires ,the diagram shows what gauge & color. However are modern / new rolls of wire still gauged the same way. I need to replace a few wires that run from the ignition switch to starter relay, the originals are cracking & perishing quite bad. ( probably due to heat off the engine) some of the wires seem to have quite a thick insulation. But modern wiring seems to be thinner even if the amperage rating is the same. I am no auto electrician but still capable of doing small jobs like this, just the Tech side is letting me down. For those that are familiar with the 60/61 Imps I will probably need to replace Gen. to reg./ reg to ammeter/ light switch.


From Robin:

Gauge is still the same. Smaller the number the heavier the wire. Newer wires tend to use different types of insulation which are thinner yet "better". As long as you you use the same wire gauge and route the wire properly so it does not chafe not too much to worry about. You can buy wire with heavier insulation if so desired. There are places like that specialize in older auto wiring and supplies.

From Arran:

I gather that when you are speaking of the cloth covered wire you mean the reproduction stuff and not used. In the old radios sometimes the insulation is still good, other times it is as hard as a rock and cracks every time you bend it. I have also run into some sets that use some sort of gum rubber insulation without the cloth, some of this stuff actually melts and drips from age! I think that some wire manufacturers never vulcanised their rubber insulation.There are a couple of outfits that sell the stuff, sun wire being one of them, most catering to those with vintage electrical equipment. However cloth wire is usually double the cost of ordinary wire. A good inexpensive substitute is what some would call Celanese wire. It has vinyl insulation with a cloth jacket made out of Celanese, the same stuff used in cigarette filters, and it is quite burn resistant. I have never bought any but i have pulled yards of it from old T.V sets.

Question from Patrick (1964):

In my 64 Crown Coupe a couple years back I had a couple of wires burn. One of the wires ran from the starter solenoid through the bulkhead connector then to the amp gauge (red wire) the other wire (black wire) ran from the amp gauge which connected to 4 other wires: Battery feed, ignition switch (Battery), headlamp switch, bulkhead connector. The scorching continued through the bulkhead connector again (black wire) which leads to the alternator. The bulkhead connector incidentally as one could imagine went through a meltdown where these wires were located. Needless to say any short term repairs wont suffice. I have recently purchased on Ebay another wiring harness from a 64 although w/o A/C and auto pilot. My car has A/C but no auto pilot. I'm wondering what the best suited option I should take to fix this problem. My options as I see it: 

1. Completely replace the harness and add the A/C wire(s). 

2. Take the bulkhead connector and needed replacement wires from the new harness and use them for the repair as needed.

Before I undergo this endeavor, I will want to ensure I don't do anything "Stupid" as it were. My goal is to resolve the problem without the risk of an electrical fire on the road in the future. I understand taking a 64 dash apart to access the areas for the complete replacement job isn't the easiest. Plus I'm not even sure the dash has to be taken apart. So if anyone else has some experience and give me come advice on doing this project, please feel free to let me know what to do.

Follow-up from Patrick:

Here is a url which goes into extensive detail about this particular problem.  It is as follows: 

My problem began a year and a half ago with the wires burning as described in my earlier post. I am fortunate it wasn't worst although it was no picnic rewiring the repair. It didn't take long though until my repair proved to just cause the same problem all over again. I would drive about 5 miles and start smelling plastic burning and seeing smoke. By this point all the related wires under the dash were short, no very short and a reminder of how it is working on my MGB. Six hands wouldn't have been enough to do the repair at this point. After knocking out a few dash bulb and ruining the sockets and pulling the headlight wire so much it shorted out on the steering column also by then my hands were a little sore and cut up. My hands aren't made for under the dash work period. The option outlined in the url to me is simple and solves the problem once and for all. I will loose my amp gauge's function but the trade off is worth it. Besides who will know besides myself and a thousand other readers... The materials cost a $10.00 at my local parts store.

Question from Don (1964-66):

On the 1964 thru 1966 Imperials were the wiring harnesses for the doors all the same. Did they put in wiring harnesses fully loaded (as in power windows, power vents, door locks) or did they put in harnesses for what was ordered only? The reason I'm asking is if I want to add P\V and PDL's to a car not equipped, is the harness wired for all options?


From Brad:

I've had the door panels off of my LeBaron and there is NO additional PDL wiring in the door; only window wiring. Mine does have PVW's and is wired as such. You'll need the switch bezels for the arm rests when you do this upgrade. My drivers (and I assume the passengers) bezel IS stamped for the lock switch cut-out, but it would take a lot of polishing to make it look right were I to simply cut out the tab. I'm sure whoever has the wiring harness also has the switch bezels. I had asked Bob Hoffmeister about this PDL setup and he said he had the stuff. I just don't have the cash right now to do the upgrade. He probably has some harnesses for all 3 (PW, PVW and PDL) too.

From Norm:

I do not believe the whole set-up for the door locks is in there. It involves relays and quite a bit of wiring. My 64 convert did not have this stuff in it.

Question from Gary (1967-68):

Need some help identifying the placement of the a/c compressor wiring. My service manual shows a blue wire and a brown wire to the compressor. I have a blue wire with female connector from the compressor that matches the blue wire from the wiring harness nicely (except the gauge from the harness is smaller than out of the compressor).  I also have the brown wire from the harness but do not see an obvious place to connect on the compressor. In other words, there is not second wire coming from the compressor which I know to be complete. There is a metal bracket plate affixed to the compressor with a fitting that looks like brown wire will slide up onto but obviously would provide a ground. I would appreciate it if someone could look at their compressor and identify where the two wires connect. 


From Dick:

According to the service manual for the 69 ( which I am quite sure is the same), the brown and blue wires both go to a "T" shaped double connector, with both wires being 16 gauge, and the blue wire connects to the vertical part of the "T" via a separate plug and receptacle that is closer to the compressor. Perhaps this is the connector you have found. Follow that wire to it's termination, you should find the "T" shaped connector. The other wire on the latter connector will be the connection point for the brown wire.

From Norm:

What I have discovered so far is that if you attach the brown wire to the blade on the compressor (and that is where I believe it is intended to go because the book shows a representation of that part and the previous year cars without ATC do not have the additional place on the compressor to attach anything) it causes a tremendous discharge to the electrical system of my 67. I have left it disconnected, just as I found it. But it must have been there for a reason.

Question from Brad (1966):

Before I go to the trouble of stringing wire, does anyone make wire harnesses for my '66?


From Gregg:

It seems that folks neglect two aspects of their cars...the drive shaft and the wiring. I learned the hard way when my butchered wiring harness under the hood fried, nearly taking my dash harness with it. Fortunately, I got a harness from a 69' 300 that was almost identical and cannibalized it. after hours spent under the dash, plus a new ignition harness (electronic) the car finally ran again, though it sat for three months. and when cruising the ammeter reads just right of the middle, where it should be. the engine harness you can get, but the dash harness maybe a no- go. Y n Z in Ca only makes up to 60 or 61...Chrysler started using molded plastic connectors in the 60's, and they don't get into that. I f I had been really desperate, Ken Rubins in NY might have repaired my harness, because he has all the tooling for these connectors. The fact is, that all the folks that make wiring are so busy with filling orders with A, B, and E bodies, you can wire an entire muscle car with repro harnesses. C and Y bodies are left out in the cold. You will probably have to run your own wiring, unless you can convince someone to copy yours. Take care of what you have, its not replaceable.

From John:

Chrysler started using the molded connector in 1960.

Question from Brad (1966):

While I was fixing my vibration problem I also wired up the fuel tank sending unit. I ordered a ground strap from Year One and installed it on the unit outlet and attached it to the frame grounded fuel line. I don't have a multi-meter but I do have a test light. I checked the wire at the tank for current. I got a light with the key ON and OFF. It was kind of weird. It "pulsed" dim to bright. My thought was that this wire was in the same circuit as the clock, could it be? It pulsed like the winding mechanism of a clock would as the contacts close and open. I have another sending unit so I wired it into its own circuit using the tank wire for power and grounding it to the frame with the test light. As I moved the float back and forth, the pulsing light got brighter and dimmer. I guess that only proved that that sending unit works. I checked the gas gauge with the float at both the up and down positions. The gauge didn't move in either state. I didn't pull the unit in the tank out. I don't own a brass drift and didn't want to chance causing a spark (the seal leaks a little. I got a new seal too so I'll do it all at one time). My questions: Is the tank wire supposed to have power to it at all times? Is it in the same circuit as the clock? I seem to have lost time during all this. I there any danger in leaving this wire attached to the sending unit if the wire is NOT supposed to have power to it at all times?

Reply from Dick:

The pulsating light means your gauge regulator is working correctly. The last time we talked, this was the wire that had been grounded, right? As I said at that time, grounding the wire TEMPORARILY should take your gas gauge to a full indication. If it does not, the problem is with the indicator or the connections to it, regardless of any other situation at the rear of the car. Leave the tank sender alone until you figure out the following situation. Your sender may be just fine.

Turn the key on (at least if your car were normal you'd have to get power to the circuit), then take your test probe and verify that you see the pulsating signal on the "S" terminal on the fuel indicator, and a solid ground on the metal of the indicator unit.

The way to verify a solid ground on anything is to connect your test probe "grounding" alligator clip to something you know has solid 12 volts on it, like the main body feed from the battery, and probe with the sharp point on anything metal to verify that you have a good connection, the light will light (yes, the polarity is reversed, but bulbs don't care), then probe your gas indicator or mounting point to verify a good ground.

90% of the time, this will locate your problem, but if the wires are all connected right and the indicator still doesn't respond to grounding the "S" terminal, the indicator is indeed burned out, (which I suspected way back when this all started and you said the wire was permanently grounded at the rear). One can get away with grounding the sender's wire for a few seconds to verify that the dash indicator is responding, but it will overheat and burn up if the wire is left grounded for more than a few seconds.

The fact that the power is there all the time is a separate but definite problem. It means your accessory circuit is on all the time, and if you leave it that way, it will be running your battery down slowly, and could also cause other problems. Please consult your FSM and the IML archives to see how this circuit works and is supposed to be connected. (The gauge sender wire comes from the gauge regulator AKA voltage limiter, that's the dingus that does the "pulsing") and the archives are jam-full of posts about it, some quite recent.

You are going to have to get at the connections at the gauge cluster. I suspect the car is incorrectly wired at the fuse panel, with the "I" wire to the regulator connected at the wrong terminal on the fuse block, but you are going to need to carefully follow the colors and connections as laid out for you in the FSM to dope this all out. It could indeed be connected to the clock power source, but it shouldn't be! If you don't have an FSM, you are going to have to get one to troubleshoot this problem. Are we talking about the 72 or the 66 here? I'm assuming the 72 in all the above, but since I am not personally familiar with either of them, I'll have to trust your eyes to tell me what you see under there. As a temporary expedient, you could just lift the black wire off the gauge regulator/voltage regulator terminal, that should stop the constant current drain. Be sure to tape it up, it is hot all the time (and shouldn't be, it should only be hot when the key is on!).

It ain't rocket science! (I know, I've done both!). Just disconnect the battery and slither under there with a good light and a comfortable pillow. Take your shoes off so you don't soil the headliner!

This page last updated February 18, 2004.  Send us your feedback, and come join the Imperial Mailing List - Online Car Club