1999 Chevy Suburban brake/signal light problems please help

I have a 1999 chevy burban and for some reason I've having this problem the my one brake on the passanger side won't light up when you press the brake but the other side will. And also when I apply the turning signal on the passanger side it blinks really fast and you can see the front singal flashing fast but the back does not flash at all. So for some reason the brake and signal lights don't work at all on the back passanger side. But the running lights do go figure if any one could help me i would really appreciate it. :banghead:

They are dual filament bulbs in the tail lights/stoplights.
Check the bulbs. Never rule out the obvious.

Taillight boards are common on these trucks to go bad...

I have checked the bulbs and the fuses and everything looks to be fine. I havn't checked the flash relay but why would one side work and not the other.

Completely remove the taillight housing. Bolted to it is the Tail light circuit board(held on by 2 screws). These are very common to go bad.

GM Part No. RH 16511566
LH 16511565

But it not like they don't light up at all. They will light up if I just have the running lights on and also if I have the reverse lights on. That all works what doesn't work is when I step on the brake and when I use the turn signal it flashes really fast in the front and you caqn see it but it does nothing in the back. Do you think replace the circuit board will still help it?

Their are 4 possibilities here...

Bulb. Tail light circuit board. Bad connection somewhere. Broken wire.

From your posts, everything works fine, Left & Right, except the right side Stop/Turn signal light. If BOTH filaments in the bulb are good, bulb is OK. Check the connection in the circuit board(where the bulb plugs in). Check the weatherpack connector that plugs into the circuit board.

If you haven't found it by now, start tracing the wire forwards...

Yah well what really throws me off is the the running lights and reverse lights work on the back just the signal and the brake don't work. So if the running/reverse lights are working then its getting some kinda of current back to the lights. It just don't light up brighter when you hit the brake and doesn't flash when you hit the turn signal.

I don't think you understand DUAL FILAMENT ...

Replace the brake/turn signal bulb.

all the bulbs are ok. I checked all of them in the front and the back. The back bulbs light up when the running lights are on they just don't get brighter when I hit the brake or engage the turning signal. The frint turning signal will flash. but it flashes really fast. Which when I first seen it I figured a bulb was bad so I went and bought bulbs but non of the bulbs were bad when I took off the light cover. The connection looks clean. So I'm not sure why this is happening.

I have the exact same issue on my 99 Sub. Have you figured out your problem? Any help would be great.

Hey had same problem with my 99 suburban. I did change bulb and it now works fine. Got other probs. LoL.
replace bulb only few bucks just give it a try.

I'm in agreement with PamsDad. I don't think you guys are understanding what we are getting at. The bulbs are dual filiment, meaning that if you turn on the running lights, the smaller filiment will illuminate. If you hit the brake or turn signal, the larger filiment will illuminate. Try removing both tail lamp assemblies and swapping them side to side. Just plug them in and let them dangle from the sides of the truck. Then see if your turn signal rapid flashing then follows the lamp assembly. Have a helper handy. If it does follow the lamp assembly, go replace the tailight boards as was suggested already. You were even given part #'s! If the problem does not follow the lamp assembly, then you can try replacing the bulbs themselves, check the sockets for no contact, or end up tracing wires. By the way, do you have a turn signal harness "T" adapter installed for towing? It prevents from having to cut into the factory wires so you can wire up a trailer. Don't count out a bad connection there either if you have one. -Chris

Just to share my experience on a 98 Suburban...
Bulb looked OK but changed it anyway. Circuit board discolored, grease dirty and dried up. Cleaned up board and used new grease with new bulb, worked OK for about a week, then same problem re-appeared. Changed circuit board with part number from Pam's Dad (Thanks!). Now working Fine.

Hey Gang,
I own a 99 'burb. Got tired of buying new circuit boards at $75 each.
The problem appears to stem for a poorly designed plastic to metal
fit in the center light bulb contact point. It probably happened during
the strike that occured during the production of '99 Suburbans. Some
Quality Control guy wasn't watching is my theory.
To test your circuit board for the problem I have seen on several
'burbs, just clean the contacts - ESPECIALLY IN THE MIDDLE BULB
SOCKET - then wiggle a good bulb right and left with the turn signal
on. If it starts flashing when pushed to one side (7 out of 8 that I
have found are that the bulb lights up when it is pushed to the inside)
put a small bit of cardboard into the plastic grove to hold it solidly
to that side. It is just plastic there and doesn't touch any contacts,
just the side of the bulb. Remember to replace the cardboard when
you get a new bulb down the road a piece.
Hope this saves you some money and aggravation.
Quasar

i as well have a 99 burban, ive had quit a few issues the past few months, fuel pump quit working changed it and when i did there were arking signs on the pump, the turn signals,hazards and brake lights quit, turned out to be the switch at which it arked as well and quit then boom no probs. then a couple days ago right rear tailight,hazard and brake light quit, not the bulb, the circuit board got hot apparently changed it, and it still didnt work, i just finished tracing wires and right at the back bumper in the center there was a broken wire, the green one, it had split and arked now i redid that wire and all is fine. hoping no more electrical quirks, but i would check the wires at the center of the back bumper for broken wires,melted or such. hope this was a help.

:crying:I have a similar issue, with my 97 burban, and yes I have replaced and even wiggled the bulbs. I have taken working bulbs from the passenger side and then placed them in the drivers side, they no longer worked. I returned the bulbs back to the passenger side and they worked again. This eliminated the possibility of bad bulbs and leaves me with a bad wire or a bad circuit board. To determine the problem I swapped the driver side assembly and the passenger side. The non functional turn signal and brake light has now moved from the drivers side to the passenger side, so this eliminates the wires. I have now replaced the old circuit board with a new $75.00 circuit board. Wow thought I solved the problem, it was only fixed for a couple of weeks, now the new one has malfunctioned. SO, can anyone tell me what would cause me to burn through a circuit board every two weeks.

I'd be curious to see if there is an apparent burn mark on the circuit boards where the weak component was fried...diode, resistor, etc. If it is the same component, then it probably isn't the board that is the root cause unless somehow you got two boards ten years apart with the exact same defect. If you have a multimeter, you might try measuring the voltage across the dead component...could be a clue.

I'd also take a second look at all the ground wires from the light harness to make sure they aren't rusted and also any stray trailer hitch wires that may be contacting the body and grounding out.

dou you have trailer wiring harness on the back if so the end is probably full of greenish crud disconnect it

I had a problem similar to what has been described, on my brother's 1997 Silverado. I switched the circuit boards (left to right) and tried the signal and it worked on the left, but not on the right, proving the problem was unique to the LH board. I put the LH board back on the left side, hooked it up; I slowly wiggled the middle bulb and discovered it began to blink properly with pressure to one side.

Thereafter, I cut an empty plastic soda bottle and fashioned a wedge/spring from the plastic to keep pressure on one side of the bulb. I removed the bulb, inserted the plastic wedge and reinserted the bulb. It works fine, now. Thank you for the idea! Cheers.

My brake lights do not come on and neither does my emergency flashers. when i turn on the flashers, the turn signals will not come on. When I turn off the emergency flashers turn sigs work.

I had similar problem with blinker and brake lights in rear 99 suburban..
2 years ago on vacation had to stop in Kentucky to replace a bulb ... turned out it was the circuit board...so I replaced it $75 or so
Now it did the same thing again so I changed the circuit boards from the other side, the problem was not the board I searched for a loose or broken wire in the trailer hitch harness and low and behold I actually found a broken wire It was up on top of the gas tank but i was able to run a jumper wire to make the connection .works fine now but I never thought it would be a broken wire there ...just got to keep it dry from all the snow on the Michigan roads
Hope that helps ..

I have a 96 K1500 Suburban. I've been reading through this thread as I've been chasing down the same issue on the right rear. The fix to my problem tonight was the trailer hitch electrical "T". It was pulling apart, creating a non ground issue. Nylon cable ties fixed the problem. Hope this helps.