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PRBLMATIC97

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Discussion starter · #1 ·
Swapped the led taillights the PO has installed with oem taillights and led fixtures because the lights that were previously on the Jeep had dead leds and were starting to go one by one. So after my install I tested to see if all the functions work and they all work except for my left turn signal. Every time I put my left indicator on the relay Bugs out and clicks many times but the turn signal does not flash.
Headlights on.. rear brake lights turn on and do not turn off and I have no turn signals in the rear
Headlights off.. Brake lights work when brakes are applied but when turn signals are on the hazards blink in the rear
I cleaned my grounds and I checked my fuses
 
The early TJ flasher units are not LED compatible. The taillights you removed must have had a diode in them. The easiest fix is to get an LED compatible flasher unit from an auto parts store. I have not done it yet, but they say a 4-pin unit will work in place of the OEM 5-pin unit. The flasher unit is located under the steering wheel.
 
Did you swap out the flasher relay? That’d be my guess as the culprit...
 
Discussion starter · #4 ·
The early TJ flasher units are not LED compatible. The taillights you removed must have had a diode in them. The easiest fix is to get an LED compatible flasher unit from an auto parts store. I have not done it yet, but they say a 4-pin unit will work in place of the OEM 5-pin unit. The flasher unit is located under the steering wheel.
Just went to quadratecs website where the old lights came from and the tail lights came with the LED flasher so I am assuming the LED module is the one that is in there because prior to me swapping the lights worked fine reason as to why I wanted oem is because the LED from quadratec is just not my style and I figured that I can put LED bulbs in replace of the standard filament bulbs and it would work out just fine.
 
Did you swap out the flasher relay? That'd be my guess as the culprit...
The LED flasher relay is in there now because that is what came with the LED tail lights (my assumption) because the tail lights were working fine prior to me swapping, swapped them because the LEDS were blowing on the old set of lights
Don't assume it's still good. Crazier things have happened changing parts around. This is the one I just installed in my TJ...

https://www.amazon.com/gp/aw/d/B000JZ79NC?psc=1&ref=ppx_pop_mob_b_asin_title
 
Don't assume it's still good. Crazier things have happened changing parts around. This is the one I just installed in my TJ...
I also forgot to mention that whenever I depress on my brake pedal my running lights turn on when my headlights are off
I wonder if you're in need of a new brake light switch. Or possibly some weird wiring issue. Hopefully none of your wiring got messed up changing parts around. I'd double check everything. Maybe even install stock bulbs and see how it acts...
 
Discussion starter · #9 ·
I wonder if you're in need of a new brake light switch. Or possibly some weird wiring issue. Hopefully none of your wiring got messed up changing parts around. I'd double check everything. Maybe even install stock bulbs and see how it acts...
I did and it reacted the same as the LED bulbs, I dont get whats going on with this jeep :crying2:
 
Brake light bringing on the running lights could be bad grounds at the rear lights. They ground through the mounting screws so double check they are clean.

You could also try cycling the hazards on and off several times in case something funky is going on in the multifunction switch. The brake light feed goes through the switch, so it may be something wrong with the contacts inside it. Oxydisation and corrosion in the switches can cause problems. If cycling the hazards improves things, one option you could try before replacing the switch would be stripping, cleaning and regreasing the contacts with dielectric grease.

This would help if you wanted to try cleaning the switch contacts.
https://www.jeepforum.com/forum/f9/indicator-blinker-not-cancelling-switch-repair-write-up-421210/
 
I also forgot to mention that whenever I depress on my brake pedal my running lights turn on when my headlights are off
The cause is the way the circuit is wired and LEDs vs. incandescent bulbs. When you press on the brakes, electricity flows through the brake light bulb, lighting the bulb, and then flows to ground. Some of the electricity flows from the brake light side to the running lights. An incandescent bulb will not light because it needs more power than the trickle that it is getting. LEDs, however, need very little power and may light.

This video does a good job explaining the problem.

 
Discussion starter · #12 ·
The cause is the way the circuit is wired and LEDs vs. incandescent bulbs. When you press on the brakes, electricity flows through the brake light bulb, lighting the bulb, and then flows to ground. Some of the electricity flows from the brake light side to the running lights. An incandescent bulb will not light because it needs more power than the trickle that it is getting. LEDs, however, need very little power and may light.

This video does a good job explaining the problem.
so what you're saying is that i need a ballast that before the LED and doesnt pass through the LED to get to the ground ?
 
Ignore the video. Ballasts are only needed to fix a fast flash if an LED compatible relay has not been used. That isn't your problem. Your problem is a bad ground at the rear lamps, or current leakage within the switch.

You've changed the rear lamps so bad grounds are a possibility. Check the grounds (mounting bolts) at the rear lamps, and see what that does.
Try cycling the hazards on and off to wipe the switch contacts to see if it helps. I'm not clairvoyant but if cycling the hazards helps, a new turn signal switch is in your future.

I should have thought to add this earlier but you can also remove the multifunction switch and test it for continuity.

Image
 
so what you're saying is that i need a ballast that before the LED and doesnt pass through the LED to get to the ground ?
No, you should not need to add a ballast. I went through this when I put LEDs in my MG. I found that not all LED bulbs are the same. Some are very cheaply made. Some have very different light patterns. It was not as easy as just swapping LED for incandescent bulbs.

Check the bulb socket to verify there is no gunk that could pass current between the two pins. Check the ground too. Headlights on cause both parking lights and brakes lights to glow could mean current is flowing backwards from parking light ground through brake light, but I thought LEDs would not light if wired backwards.

The problem could be in the turn signal stalk. I replaced mine a few years ago because sometimes the left turn signals would stay on when the switch was off. It was an easy swap.
 
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