Ignition problem

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Flairbird64
Posts: 18
Joined: Sat Feb 13, 2016 5:17 pm

Ignition problem

Post by Flairbird64 »

My problems started when I found the harness in my sons 65 Special Landau was melted at the connectors behind the dash. So being a good Dad, I thought I would have a new wiring harness made. I got everything connected and when I tried to start the car, it would fire, but when I release the key, the engine stops. There is 12.5 volts going to the solenoid when the key is turned th on position. The front parking lights also stay on all the time with the key energized, but not the tail lights. The car will stay running if yo jump the coil to the voltage regulator. Any ideas?
BillT
Posts: 74
Joined: Mon May 02, 2016 2:25 pm

Re: Ignition problem

Post by BillT »

(I hope you disconnected the coil from the regulator, or that the points were not closed, as the coil will likely overheat if connected to 12v for a long time. )

My first thought is the new harness has the power to coil resistance wire going to the front parking lights – and probably visa versa. If this is the case the front parking lights may be on, but they should be dim due to being powered via the 1.3 ohm resistance wire mixup. The car starts now because 12v power is going, briefly, to the coil via starter solenoid with the key in the start position, but not continuing to run because this power source goes away when the key is released and the normal run power is not getting to the coil.

I’d try turning on the parking lights to see if the front ones work OK (bright). If not, try to start the car with the parking lights on. If it runs, then it’s pretty obvious there is a mix up in the parking light/coil resistance wiring in the new harness.

You can also just check the voltage at the coil with the key to ignition/run. You should see battery voltage, or less if the resistance wire is there and the distributor's points are closed.

For my '64, the schematic shows the resistance wire under the dash, pink, and with a connector at each end. I don't see how you could have mixed the connectors as they should be part of the new harness, but the manufacturer could have.

Keep us informed.
Flairbird64
Posts: 18
Joined: Sat Feb 13, 2016 5:17 pm

Re: Ignition problem

Post by Flairbird64 »

Okay, I figured out the parking like proble. It appears that the company that made my new harness crossed the wires at the connector. I cut and spliced that and the lights work as they should.

I still have a problem with the car dying when I release the key. I think I may have discovered that problem, but hope someone here will confirm. I traced the pink wire behind the dash. One end plugs into a red with green stripe wire that goes to the ignition switch. The other end goes to a green three prong plug behind the passenger side dash. I then checked the resistance on the pink wire on my old harness and it zeroed out. Then I did the same test on the pink wire on my new harness and it jumped up to 6.5 resistance. What would cause this?
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sseebart
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Location: Northern California
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Re: Ignition problem

Post by sseebart »

Flairbird64 wrote:I still have a problem with the car dying when I release the key. I think I may have discovered that problem, but hope someone here will confirm. I traced the pink wire behind the dash. One end plugs into a red with green stripe wire that goes to the ignition switch. The other end goes to a green three prong plug behind the passenger side dash. I then checked the resistance on the pink wire on my old harness and it zeroed out. Then I did the same test on the pink wire on my new harness and it jumped up to 6.5 resistance. What would cause this?
A reading of 6.5 sounds about right for the resistor wire. Are you saying that the old wire has infinite resistance?

It sounds to me like the wires attached to the "start" and "run" poles on the ignition switch are reversed, especially since you've found a similar condition in the parking lights.

~Steve
Flairbird64
Posts: 18
Joined: Sat Feb 13, 2016 5:17 pm

Re: Ignition problem

Post by Flairbird64 »

Well sadly, I have been forced to throw in the towel. Every time I correct one problem with this harness, something else goes out. Too much voltage going to the dash bulbs blowing them out. Turn signals and brake lights were working and have now quit. The Thunderbird vendor I bought the harness from refuses to return my calls or answer my emails to resolve the problem. So I'm ripping this dash back out and sending this harness back to the Thunderbird parts vendor and filing a dispute on my credit card. Hopefully I will some day get my $2000.00 back and I can start over with a reputable supplier. I have never had such a bad experience with any Thunderbird parts dealer and I've purchased from most of them. Now I have a car with no wiring at all. The sad part is that it was my sons car and I was trying to do this as a gift and now I've just made a mess of things and my son is without his car. Hind site is 20/20, but I should have just taken the car somewhere and had them re-wire the car from scratch using updated wires and breakers. I just wanted to have the car as original as possible

I'm an idiot
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paulr
Posts: 1800
Joined: Mon Nov 05, 2012 12:03 pm
Location: Seattle

Re: Ignition problem

Post by paulr »

Don't beat yourself up. Beat up the previous "mechanic" who rewired stuff.

If I was buying new harnesses for the car, I'd start by comparing the harness to the Osborne manual. It contains photocopies of the original schematics used in assembly, and they're the only schematics I trust. That's the first step to making sure your new harness is accurate, particularly considering how much they cost. Next, you can examine the existing wiring that came on the car as you bought it. With the dashboard out, you will have success accessing every part of the harness. Not everything going on with this car is due to the harness. I would have to really study the entire charging system to see what changes were made and address them. Look for aftermarket crap people added. Inspect switches (turnsignal/stop light) that have failed. Check all connectors for corrosion or broken leads. Check every ground for clean contact. This may sound like throwing spaghetti at the wall to see what sticks, but that's only because you are in the wild world of Thunderbird electrical systems. A person thinks he'll buy a new harness and everything will be solved, but this car is hiding some other defect or defects that combine to produce failures. With electrical, I always start with the book; troubleshooting sections in the manual sometimes reveal clues not directly related to your question, but rather tip you toward investigating where you should be. It's an elephant, and you have to eat it one bite at a time. The whole elephant, not just one harness.

Did I read this car is a '65 SL? Fergodsakes, this is a mid-century classic gem and there aren't any more. Get in there and do it.
Good luck!
Paul
VTCI 12014
Registry 45122
'64 Landau HT
"Beer, now there's a temporary solution!" ~Homer Simpson
tbird
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Joined: Sat May 10, 2008 11:07 pm
Location: Tyndall MB. Canada

Re: Ignition problem

Post by tbird »

Flairbird64

Here is a list of publications that you can not afford to be without they will help immensely with troubleshooting and repairing issues with the car. The Thunderbird s of the 60's and beyond were a car that was ahead of the times with new technology in every new model and literally miles of wiring and switches & relays all over the place. I may have provided this to you before and you have the books if you do dig in and start locating the issues.
Almost everyone of us have went through this when we got our first Thunderbird but we worked our way through the problems.

Owners Manual (used or Jim Osborne Reproductions)
Thunderbird Shop Manual (used or Jim Osborn Reproductions)
Body Trim and Sealant Assembly Manual (Jim Osborn Reproductions)
Electrical Assembly Manual (Jim Osborn Reproductions)
Wiring Diagram Manual (Jim Osborn Reproductions)
VTCI Original Factory Specifications (VTCI Country Store, available to members only)
These must be for your year of vehicle as there were many changes made from one
model year to the other.
Most of these items should be available from your favorite Thunderbird supply house or
directly from Jim Osborn Reproduction, cost will be about 125.00 plus shipping cost
Jim Mills
VTCI # 8071
VTCI 1964-66 Technical Editor
2002 Thunderbird
1965 Convertible
1962 Convertible (in progress)
1959 Ford Retractable HT
Many parts cars
Flairbird64
Posts: 18
Joined: Sat Feb 13, 2016 5:17 pm

Re: Ignition problem

Post by Flairbird64 »

Thank you Jim and all. I think I may have found the ignition problem. As I was re-installing the brand new harness back into the car, I found this. The loom surrounding the resistance wire was burnt through and it looks like there is a resistor in line with the wire. Now the question is, what could have caused this to burn up the resister?
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