Chasing down multi ill-wiring, 68 Newport - down the rabbit hole

Mike McGuire

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Hey Everybody,

HISTORY:
It started out as chasing down why my headlights don't work.

The head lights initially (as received with Rupert) only worked on high beams only, leading me to start with the hi-low dimmer switch (on the floor).
The wiring looks fine, and checking out the functionality of the switch (looked good), swapped it anyway to remove that suspect from the list.
(Ohm-ed out the bulbs too, all good)
After replacing the foot switch, a test revealed that none of the head lights worked at all. I rechecked the switch and connectors and they appeared ok, glad I didn't fumble that.
While wondering what happened, I jostled the under dash harness around a bit and viola the head lights returned to the ON state, briefly.
This lead me to investigate wiring around the fuse box. This turned out to be a dead end as all looks great for the year, nothing rotted, mouse chewed or melted.
Then I lost the tail lights, and rear parking lights.

At this point, I thought, best to return to basics, and removed the dash (lowered the column a bit) to get at the connectors.
(I pinned out the head light switch, all looks good).
On the red side of the ammeter 12V, on the black side 11.3V. A little while later 0V. A little while later the voltage at the black terminal reads 11.3V again.
Then the red terminal read 0V.... (now I am going full nuts), then 12V again 5 minutes later...
I checked the lower part of the fuse box and when the key is 'ON' the accessories all read 12V, which I think is good, (pretty sure). (wipers work, etc.)
The other half reads 0V. Checking the black ammeter lug, it reads 0V, then 4.6V, then 11.3V again... I rationalized the ammeter is bad. (?)
I have an extra dashboard, and am considering an outright swap, as replacing the ammeter itself doesn't look straight forward.
For trouble-shooting purposes I am considering just landing the black and red ring lugs on the red terminal.
Also considering bypassing the bulk head altogether to remove that connection from the list as well, while continuing the game of hide and seek with the head light fault.

RANDOM RAMBLINGS:
I can't help to think there's another component in the puzzle. Why did the tail lights work at all? The head lights probably go through another bulk-head connector on the fire wall, where the aft lights route interiorly...
Might also be a good idea to clean the connector conductors and hit em with di-electric grease. A couple are cracked along the outside, assuming someone was here before and the ears got the screw driver.
hopefully someone makes reproduction connectors I can swap over out. I assume regular needle nose pliers can push the conductor fingers back out... Is this what crappy ammeters do?

So here's what I'm, planning to do:
1. bypass the ammeter
2. bypass the bulk head - (aka CBarge post)
3. clean the snots out of the bulk head connectors

Question - Does this sound like normal logic or am I missing something else here?

Thanks,
Mike
 
How is the wire connector at the steering column ? The turn signal switch is part of the tail light system.
Is your head light switch in good shape?
 
Thanks Boydsdodge,
Head light switch: the head light switch is in good shape and pins out just like a spare used one, worked when removed 30 years ago. (Top and bottom are common in full upright position, open other wise. Middle three swap common between half way up and full upright, if you can follow that.)
Wire connector at steering column: uhm.... I don't know yet. I'll have to take a closer look. Is it right on the column or nearby? How many pins/conductors ? Seems like there is more than 1 connector down there. This is an AC car with the Saginaw (-tilt/telescoping) column.

Best,
Mike
 
I don't have a 68 Chrysler manual here, I have a 68 Monaco manual and a 69 Chrysler/Imperial Manual. But I don't think either will be correct.
Look down the steering column for wire harness, might be a cover you need to remove, there should be a multi point connector have way. Look for burned, corrupted or broken wires
Electrical repairs aren't the worst, it is getting to the wires that sucks.
 
So here's what I'm, planning to do:
1. bypass the ammeter
2. bypass the bulk head - (aka CBarge post)
3. clean the snots out of the bulk head connectors
Go with the known issues. If it isn't the problem now it will be later
 
Might also be a good idea to clean the connector conductors and hit em with di-electric grease
Clean the connector with Deoxit (Amazon product ASIN B0002BBVN2 )

But leave the dielectric grease in the toolbox. Dielectric grease is an insulator (look up the meaning of dielectric if you don't believe me) and you end up smearing an insulating grease on a conductive surface. If you want to use the grease, smear a small bit on the out side of the insulator.
 
Clean the connector with Deoxit (Amazon product ASIN B0002BBVN2 )

But leave the dielectric grease in the toolbox. Dielectric grease is an insulator (look up the meaning of dielectric if you don't believe me) and you end up smearing an insulating grease on a conductive surface. If you want to use the grease, smear a small bit on the out side of the insulator.
Yes, thanks, conductive grease rather. thanks for catching that.
 
Hey Everybody,

HISTORY:
It started out as chasing down why my headlights don't work.

The head lights initially (as received with Rupert) only worked on high beams only, leading me to start with the hi-low dimmer switch (on the floor).
The wiring looks fine, and checking out the functionality of the switch (looked good), swapped it anyway to remove that suspect from the list.
(Ohm-ed out the bulbs too, all good)
After replacing the foot switch, a test revealed that none of the head lights worked at all. I rechecked the switch and connectors and they appeared ok, glad I didn't fumble that.
While wondering what happened, I jostled the under dash harness around a bit and viola the head lights returned to the ON state, briefly.
This lead me to investigate wiring around the fuse box. This turned out to be a dead end as all looks great for the year, nothing rotted, mouse chewed or melted.
Then I lost the tail lights, and rear parking lights.

At this point, I thought, best to return to basics, and removed the dash (lowered the column a bit) to get at the connectors.
(I pinned out the head light switch, all looks good).
On the red side of the ammeter 12V, on the black side 11.3V. A little while later 0V. A little while later the voltage at the black terminal reads 11.3V again.
Then the red terminal read 0V.... (now I am going full nuts), then 12V again 5 minutes later...
I checked the lower part of the fuse box and when the key is 'ON' the accessories all read 12V, which I think is good, (pretty sure). (wipers work, etc.)
The other half reads 0V. Checking the black ammeter lug, it reads 0V, then 4.6V, then 11.3V again... I rationalized the ammeter is bad. (?)
I have an extra dashboard, and am considering an outright swap, as replacing the ammeter itself doesn't look straight forward.
For trouble-shooting purposes I am considering just landing the black and red ring lugs on the red terminal.
Also considering bypassing the bulk head altogether to remove that connection from the list as well, while continuing the game of hide and seek with the head light fault.

RANDOM RAMBLINGS:
I can't help to think there's another component in the puzzle. Why did the tail lights work at all? The head lights probably go through another bulk-head connector on the fire wall, where the aft lights route interiorly...
Might also be a good idea to clean the connector conductors and hit em with di-electric grease. A couple are cracked along the outside, assuming someone was here before and the ears got the screw driver.
hopefully someone makes reproduction connectors I can swap over out. I assume regular needle nose pliers can push the conductor fingers back out... Is this what crappy ammeters do?

So here's what I'm, planning to do:
1. bypass the ammeter
2. bypass the bulk head - (aka CBarge post)
3. clean the snots out of the bulk head connectors

Question - Does this sound like normal logic or am I missing something else here?

Thanks,
Mike
before u short of the wiring get a copy of the factory service book & not the junk ones they sett o=innthe parts stores
 
before u short of the wiring get a copy of the factory service book & not the junk ones they sett o=innthe parts stores
Thanks Marty,
much has happened since I posted on this last. The headlights were all blown out, and cleaning up the grounds and connectors, as well as replacing the voltage regulator has solved all my electrical problems for the moment.
I'm not 100% sure why the head lights were blown out, but some minor welding was done, & we suspect the battery/electrical was not isolated and this blew out the Voltage regulator, that in turn blew out the head lights. Or, maybe it just croaked by itself.
We did by-pass the ammeter, removing that flakey-ness may have helped as well.
In any event the successful procedure was to start at the failure point (head lights) and work backwards.

During the off season, I'll take a deep dive into the ammeter issues.

thanks & regards,
Mike
 
Thanks Marty,
much has happened since I posted on this last. The headlights were all blown out, and cleaning up the grounds and connectors, as well as replacing the voltage regulator has solved all my electrical problems for the moment.
I'm not 100% sure why the head lights were blown out, but some minor welding was done, & we suspect the battery/electrical was not isolated and this blew out the Voltage regulator, that in turn blew out the head lights. Or, maybe it just croaked by itself.
We did by-pass the ammeter, removing that flakey-ness may have helped as well.
In any event the successful procedure was to start at the failure point (head lights) and work backwards.

During the off season, I'll take a deep dive into the ammeter issues.

thanks & regards,
Mike
ok im glad u worked it out tell me the yr & module u r working on (I lost lost what we r working on). i will search my sources for factory books
 
I was going to suggest the bulkhead connector. My headlights did this years ago and when the connector was separated the low beam terminal was nearly gone. Corrosion is common in the bulkhead area. Zero weatherproofing.
 
YES BUT U REALLY NEED A FACTORY SERVICE MANUAL IT HAS CHARTS IN IT JUST FOR PROBLEMS LIKE THIS + IT HAS A FULL COPY ON THE WIRING DIAGRAMS TOO . I USE TO HUNT & GUESS TILL MY COUSIN ( A MASTR MECANIC OF 45 YRS ) TALKED ME INTO BUYING A COPY OF THE FACTORY/ DELERSHIP SERVICE BOOK . IT HAS SAVED A TON OF GUESSING . NOW DO AS U LIKE BUT A TRUE FACTORY(DEALERSHIP SHOP MANUAL WILL SAVE U A LOT OF GUESSING
 
Looking over this, as I have a 67 Newport. Never had any electrical issues, but one day, started smoking under the dash. The fuse for the heater (fan) had overheated and melted the fuse block connection. Didn't blow the fuse, jut melted the box. That was fun tracking down the wiring. Reading further in your post you had mentioned your headlights were blown. I was having issues with my 85 ramcharger charging system. After replacing alternator, that was tested bad, and voltage regulator, still having issues of high voltage, yea, over 18 volts going through, no one could help. My headlights were blown (on low beam), burned my new stereo up, aftermarket voltage gauge pegging out, it came down to another New Voltage regulator being bad, and the alternator also. After the 2nd Alternator put on, and 3rd voltage regulator, I remember I had an old MOPAR voltage regulator I kept off of an old (1980) dodge diplomat, put it on and problem solved when the 4th voltage regulator started pegging out. The old one worked for about 6 months, could complain considering it was on my old diplomat for at least 10 years, then stored for over 10 more years. I recently replaced it and voltage regulator number 5, so far is working. The parts you get today, just don't hold up. I looked, made in Taiwan, so the search begins for NOS American made one, so I will be ready for next one. I am still just aggravated after having to replace everything New multiple times.
 
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