'86 Chrysler New Yorker help

Hello everyone,
I came across a problem that requires your electrical skills.
I recently purchased a '85 New Yorker.
It has various bugs including the stereo, trip computer and voice module.
Anyhow, the most problematic is a non functioning, third brake light.
When I got the car, I failed to check for it working.
When I traced the wires, I noticed that it was not wired onto the vehicles
brake circuit.
Several attempts later, I still cannot get it to work correctly.

I attempted to wire it onto the brake circuit at the rear, left tail light
and thought I got it functioning correctly. Then, I applied the left turn
signal, it began to go from a constant brake light to a flashing light.
What gives?? I have tried several combinations with no luck.

Can someone point out how this is suppose to connect??

Thank you,

Jesse

 

My in-laws had an 85 New Yorker.

A third brake light wasn't required until 1986.

Your subject line says 86 and your note says 85. Which one is it ?

Could be an aftermarket light if this is a 1985 car.

 

Steve,

My bad!
It's a '85 New Yorker. May be aftermarket. I don't know. Still, I'd like to
know how it wires into the system. I guess, with the double duty, turn
signal/brake circuit, it may take a miracle.

Any miracle workers out there??

Thanks!

Jesse
---------------------------------------

 

It can be wired into the brake light switch, located on the brake pedal
strut. That way, it receives power BEFORE the brake light feed is split
into two independent circuits and combined with the turn signal function
by the turn signal switch in the steering column.

 

This would be an aftermarket add-on; the center high mount stop lamp
("CHMSL") was not required by law and therefore not factory installed
until the 1986 model year. Most of these aftermarket lamps were of very
poor quality. The ones offered on the North American market frequently
came with a "logic module" enabling quick 'n' cheesy/easy hookup to the
combined brake/directional lights at the rear of many US-spec vehicles.
These modules fail with alacrity and sometimes never worked right from the
start -- when these retrofit CHMSLs were popular, it was common to see
them flashing with the turn signals, staying on all the time, operating in
opposite-phase with the brake lights and so forth.

The factory units and the better-made aftermarket units do not use a logic
module. They're wired directly into the brake lamp circuit such that they
are not a part of the turn signal circuit. This is really very much better
way to do it, though it's more effort.

The way the combination brake/turn system works is thus:

12V feed to the input of the brake lamp switch on the brake pedal bracket.
Stepping on the brake closes this switch and sends 12V feed downstream of
this switch. This 12V feed goes *through the turn signal switch* which
contains a series of contacts that can:

(a) pass this 12V feed to both rear lights directly ("no turn" position)

(b) pass this 12V feed to one rear light directly and the other rear light
through the turn signal flasher ("turn" position, either left or right).

To makeyour CHMSL work correctly without creating a bunch of new failure
points, you need to tap into the brake light switch output wire, before it
enters the turn signal switch. Run your new wire from that point back
through the factory wire channel (accessible by removing the driver's side
kickboard and front and rear driver's side sill plates) into the trunk
compartment and from there through the package tray to your CHMSL.

DS

 

You need a third brake light module - it connects to both left and
right stop/turn lamp and "combines" them.

 

My 85 LeBaron T&C had third brake light. Factory. Canada. Same car as
New Yorker.