Ok i have had sequential tails for a while. Anyways today while getting the oil changed i noticed something wrong.

Anyways, my left one does not work correctly. Only the first bulb lights up (closest one to the faux gas cap), when i have the turn signal on.

Now when i unlock my car all 3 of the lights light up on the back so there are no bad bulbs. It just won't light up the other 2 when i have hazards or turn signal on.

What could the issue be? Anything fixable, or do i just need a whole new harness?

 

I would check the bulbs,when you use keyless entry it only uses the park light,turn signal and brake are use the other element in the bulb.

 

when i unlock, all 3 of them light up. However when i lock the car and it goes to flash the sequence once, only the one lights up.

 

May be easier to test if you have someone in the car pressing the brake and turn signals hazzards etc. The bulbs are 2 filaments one for lo and one for high. So its possible that you have a partial burn out.

 

Awsome. I know what you mean. Like at night when lights are on, but you hit the break and they get brighter. I will go try this out.

 

you also might want to check for a short. when i was looking at buying sequentials the other day i noticed they said it has a fail safe wiring so if there is a short 1 light (the inner one) will always work.

 

Good to know as I have seq's too.
Best ones are the ones that are direct harness replacements, just unplug the originals, switch lightbulbs and plug in new harness.

 

This is what i have the direct plug in ones. It may be a problem with the wiring.

Now listen to this. When i lock my car/use turn signal only the first (inner bulb) lights up. But if i hit my breaks it will VERY slowly complete one sequential then stay red for braking.

All 3 lights light up slowly in a row when i hit the brake. It has to be something with the harness im guessing. Any ideas as to what to do now.

Edit: Saw what you meant about low's/highs, and yes all bulbs are working correctly. I witnessed both filaments from all 3 bulbs light up.

 

Mine also only flash the first two during locking.
The locking flash pulse is not long enough
to produce a full 3 light sequence.
Normal, nothings wrong. What brand of sequentials
do you have. Mine are CDC Dynamite Sticks.
Put your hazards on along with your headligts
to put your outside lighting into test mode.
Walk around and verify proper operation.
Replace any bulbs that dont illuminate. Then
if the problem persists, do an electrical diagnostics
check as per the Ford Service Manual.

 

I know that the locking flash pulse isn't long enough for all 3 just 2. But my right one does the 2, and my left one does 1. I believe that i had purchased mine from stangmods. There website doesn't have a vendor listed for them, so im not sure who makes them. I need to contact them.

BTW i have had these installed since about march(ish), with no problems so far. Does anyone know the general warrenty period for things like this.