No Brake or Turn Signal lights 69 Barracuda

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harrisonm

harrisonm

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Sorry for the length, but I wanted to provide complete diagnostics the first time. 1969 Barracuda 340 4 speed. Brake and hazard lights and turn signals DID work before the restoration tear-down, but the canceling cam did not work. Last winter I replaced the canceling cam with a correct looking Dorman part from Advance Auto with the column out of car, and it seemed to work. Now car is 99% done (ready for test drive), and the Brake Lights and Turn Signals don’t work. Yesterday I did a lot of research (mostly on For A Bodies Only), studied my wiring diagram carefully and checked everything. 1) I DO have power going through the Brake Light Switch when pedal is depressed. 2) With key “On”, I have no turn signals at all; no indicator lights on the dash, nothing. 3) Running lights all worked, front and rear. 4) When hazard light switch is turned “On”, the Hazard lights for the front only come on but do not flash (green dash indicators are also on). 5) This morning (after more on line research) I re-checked everything. The only difference is that now both rear and the right front running lights work, but the left front doesn’t; and the left side green dash light is on. Anyway, my research seems to indicate that replacing my turn signal switch and cancelling cam should fix most of my problems. It appears the turn signal switch also sends brake light power to both sides when the turn signal switch is in the center position. Could someone please advise. I want a second opinion before I go through the trouble of buying and installing parts. I’m not sure about the new thing with the LF running light, but brake and turn signals are more important now. Could I have disturbed something while replacing the canceling cam?? Lots of part numbers out there. Any suggestions??
 
99% of the time, when a dash turn indicator lamp comes on with park lamps the fault will be lack of chassis ground at that left or right front fixture. This applies to many brands of older vehicles, not just Chry' products.
And too many times a restore/repaint looses various chassis grounds. Scratching new paint to bare metal here and there as required I call the devil in the details.
 
The Directional flasher gets power from Brake light switch (red or pink colored wire, but if the dash lights come on , that is because it looking for ground. Check your rear tail light grounds and the front dash ground also for the turn signal switch.
 
It does sound exactly like a bad ground.
One thing I like to do in cases like this is to run 15 foot long ground wire directly off the battery, and go around touching it to the devices that dont work. (like bulb sockets and such)
It gets obvious fast if there are grounding problems.

The only other thing might be the connector under the left side kick panel may not be connected.
Also just so you know, most flasher units will not flash unless there is sufficient load on them.
So the fact that the fronts come on but don't flash tells us that the rear bulbs are not connected to the rest of the system. (loss of pos or ground either one will cause this)
 
The turn signal switch itself isn't grounded. Its mounting screws are in plastic.
A ground jumper on the steering column supports only the horn switch and column mounted shift indicator lamp, ( also ignition switch lighting in later models ).
Make sure that both flasher modules are installed. Many owners don't know there are 2 of them onboard.
 
Thanks for all the replies. I did have a bit of a grounding issue with the left front parking light. That's fixed now, and the culprit was fresh paint (good call). After hours of testing and looking at the wiring diagram, I finally figured out why my brake and turn signal lights were not working. I ultimately determined that the wires on the back of the cheap Dorman turn signal canceling cam were not making contact with the electrodes on the top of the turn signal switch. The back side of the cancelling cam has two hard wires about one inch long that make connection with four electrodes on the top side of the turn signal switch. One of those hard wires is hot when the ignition switch is “On” and the other one is hot when the brake pedal is depressed. The four electrodes on the top of the turn signal switch are sort-of in a square. Using a jump wire, I determined that the upper right hand (UR) electrode sent power to right rear tail light, the lower left hand (LL) electrode sent power to right front parking light, the upper left hand (UL) electrode sent power to left front parking light and the lower right (LR) hand electrode sent power to left rear tail light. So when the turn signal lever (that moves the cancelling cam and the hard wires on the back) is flipped up for a right turn, the wire that is hot when the ignition is on will contact the UR and LL electrodes thereby activating and flashing the front and rear right hand turn signals. Conversely, when the turn signal lever is flipped down for a left turn, the wire that is hot when the ignition is on will contact the UL and LR electrodes thereby activating and flashing the front and rear left hand turn signals. When the turn signal switch is in the neutral position, the other hard wire on the back side of the canceling cam (the one that is hot when the brake pedal is depressed) is making contact with the UR and LR turn signal switch electrode. So when the brake pedal is depressed, power flows to both rear tail lights. I bent the tips of the wires on the back side of the canceling cam up a bit so they would contact the turn signal switch electrodes, and everything worked fine, but I think I’ll still look for a better canceling cam.
 
In all my years I've never replaced cancel cam alone. I' have replaced complete switch assembly a few times. good luck
 
I went through the exact same thing when I replaced my signal cam. (exactly)
The spring wires were to close together and I had to spread them about 1/16 to get it to contact where and when it needed.




harrisonm said:
Thanks for all the replies. I did have a bit of a grounding issue with the left front parking light. That's fixed now, and the culprit was fresh paint (good call). After hours of testing and looking at the wiring diagram, I finally figured out why my brake and turn signal lights were not working. I ultimately determined that the wires on the back of the cheap Dorman turn signal canceling cam were not making contact with the electrodes on the top of the turn signal switch. The back side of the cancelling cam has two hard wires about one inch long that make connection with four electrodes on the top side of the turn signal switch. One of those hard wires is hot when the ignition switch is “On” and the other one is hot when the brake pedal is depressed. The four electrodes on the top of the turn signal switch are sort-of in a square. Using a jump wire, I determined that the upper right hand (UR) electrode sent power to right rear tail light, the lower left hand (LL) electrode sent power to right front parking light, the upper left hand (UL) electrode sent power to left front parking light and the lower right (LR) hand electrode sent power to left rear tail light. So when the turn signal lever (that moves the cancelling cam and the hard wires on the back) is flipped up for a right turn, the wire that is hot when the ignition is on will contact the UR and LL electrodes thereby activating and flashing the front and rear right hand turn signals. Conversely, when the turn signal lever is flipped down for a left turn, the wire that is hot when the ignition is on will contact the UL and LR electrodes thereby activating and flashing the front and rear left hand turn signals. When the turn signal switch is in the neutral position, the other hard wire on the back side of the canceling cam (the one that is hot when the brake pedal is depressed) is making contact with the UR and LR turn signal switch electrode. So when the brake pedal is depressed, power flows to both rear tail lights. I bent the tips of the wires on the back side of the canceling cam up a bit so they would contact the turn signal switch electrodes, and everything worked fine, but I think I’ll still look for a better canceling cam.
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