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reverse lights and turn signals swapped??

9K views 31 replies 9 participants last post by  Chrisman183  
#1 ·
2002 Silverado 1500 stepside
I put in reverse light LED's, and went to test them. Put the truck in reverse, and the yellow turn indicator came on... then, when I put the turn signal on to the driver's side, the drivers side revers light (white led) hyperflashes. What the heck could be going on? I haven't noticed this before, but I just got this truck about a month ago... could there be a relay in the wrong spot, or what the heck? I don't want to just swap the 2 fixtures b/c they won't fit, i'd have to actually cut and resplice them out. I'm thinking that's not the best answer.

Anyone?
 
#2 ·
ok some more checking revealed:
the reverse lights and turn signals are both swapped on the tail lights.
On the front lights, the turn signal is using the same light as the parking lights. and nothing is using the turn signal lights...
I looked at some drawings, but only thing I can think is the switch is all messed up or backwards or something...
the hazards in the back are flashing the reverse lights, and in front flashing the parking lights.
 
#7 ·
Anyone know what I could be checking?
I looked at all of the wiring diagrams on here, and I just can't find anything related with the reverse lighting and the turn signals. Reverse lights go through the BCM, and turn signals use the multi-function switch. It's got to be a wiring harness issue I'm almost sure because of the front flashers using the wrong bulbs, just not even sure how that's possible. Bueller??
 
#8 ·
Did you every put the stock bulbs back in to see if that fixed it as suggested earlier. If you do and they go back to functioning correctly, then it would seem to be more of a BCM issue. But, when I have problems after doing a mod, I always go back to stock to see if it is the mod itself or maybe something I did wrong when installing it.
 
#9 ·
esox07 said:
Did you every put the stock bulbs back in to see if that fixed it as suggested earlier. If you do and they go back to functioning correctly, then it would seem to be more of a BCM issue. But, when I have problems after doing a mod, I always go back to stock to see if it is the mod itself or maybe something I did wrong when installing it.
I did, and unfortunately it did nothing to change the issue. Still acted the same (except the reverse lights didn't hyperflash obviously)
 
#10 ·
You need to pull all the lamps you have replaced out and 1 set at a time reinstall and test all operations. Set being just front turn lamps for example. If issue persists pull your flasher relay and test for normal reverse light operation. If still an issue you have a grounding issue in one of your harnesses. Are these switchback LED?

It's sounds to me like you could have got the wrong socket lamps aswell. Wrong socket type..... verify your socket type (YouTube ck vs standard) and make sure the LED is the same socket type. Ck and standard sockets differ in the location of the 2 ground wires in the plug.
 
#11 ·
sounds like the sockets are switched. Obviously the front cant be doing it as well because the front has headlights not reverse lights so when you say its hyperflashing it is most likely the led you installed is in the blinker socket and not the reverse socket which i believe is the same bulb.
 
#13 ·
Lividtaco said:
If it's an LED switchback lamp then if either is installed in reverse polarity it can cause them to go solid on, flash out of sync, etc. My guess is still wrong socket type
you mean the socket that the bulbs fit into? or the type of base connection of the bulb?
either way, i think that is ruled out because the sockets that the bulbs fit into won't swap between turn signal and reverse lights. there are little tabs that slide into holes and they are not matching, i can't swap them into the wrong place even on purpose. The bulbs are right, i took the LED's out of the reverse lights and put back the regular bulbs, it still is swapped.
Also, the front turn signal bulbs don't flash, it's flashing the running light bulb instead. (the yellow tinted section never comes on no matter what lights i am using. the middle light in the bumper section comes on with the headlights, and it also flashes with the flashers/turn signal)
 
#15 ·
Have you verified the socket type? Are you 3157 or 3157k? WHaT lamps are you replacing with LED? Odds of you simply swapping bulbs and all of a sudden having a BCM issue is highly unlikely. Either your using 1 or more sets of lamps using the wrong socket type as I stated before, polarity is reversed,or you have a bad LED. REPLACE stock bulbs with LED 1 at a time.....starting with ALL LEDS OUT

And link the lamps you are using to replace
 
#16 ·
i havent verified the socket type, but it is doing it with no LED's installed. I only put LED's in reverse sockets, but they were already swapped before i did that, i just didn't know because the reverse lights werent hyperflashing with the old incandescent bulbs. I'll check the sockets today and make sure the bulbs match and that the sockets are the same. But i knowingly tried to swap the sockets the first day i noticed and they wouldn't fit, so I thought they were different. I'll double check that. If they're supposed to be the exact same, then that might be something...
thanks
 
#20 ·
The green is reverse and blue is turn signal on my GM vehicles I've had, which is opposite of what you're showing. But, they are functioning the way my other GMs do that have had separate brake and turn bulbs (My 07.5 uses the same for brake and turn so can't use that as a comparison).

If you turn the socket 90 degrees the tabs all match then and it should fit the other spot, although the lock tab (on the right side in the pic) would not line up with the tab on the housing so they wouldn't lock in place. The way you have them they are locking in place, right? Can you get a picture of the back of the housing with the sockets installed?

Front DRL and turn signal bulbs should be the same way, both 3157 and sockets could swap between the two locations.

Where are you located, by the way? If around here (central Ohio) I'd be glad to try to help you figure it out.
 
#22 ·
Thanks man but I'm in Alabama. Yeah they are locked in I can't get them locked like you said if I swap them. Which means something upstream is swapping the reverse/signal circuits. And I'm pretty sure it's the same in the front if you say they're both 3157 (I haven't actually checked the situation up there just know that the yellows don't flash, the drl do)
 
#23 ·
SparkyJJO said:
The green is reverse and blue is turn signal on my GM vehicles I've had, which is opposite of what you're showing. But, they are functioning the way my other GMs do that have had separate brake and turn bulbs (My 07.5 uses the same for brake and turn so can't use that as a comparison).

If you turn the socket 90 degrees the tabs all match then and it should fit the other spot, although the lock tab (on the right side in the pic) would not line up with the tab on the housing so they wouldn't lock in place. The way you have them they are locking in place, right? Can you get a picture of the back of the housing with the sockets installed?

Front DRL and turn signal bulbs should be the same way, both 3157 and sockets could swap between the two locations.
Thanks, but i just realized, I can't swap the sockets at all, even without it locking. When i rotate one of the sockets 90 degrees or whatever, the tabs all line up, but the big fat tab is lined up with a small tab slot, so it won't even go in that way... sheesh. I'm just considering swapping the pins at the harness at this point. I'm just worried about the front flashers, i have no idea how to correct that since it isn't just 'swapped' like the back ones are. But the front isn't bothering me as much at this point. Just wish I could figure out what is going on... maybe the BCM was worked on at some point? just throwing things around in my head now :oops:
 
#24 ·
On my 2000 2500, I have a junction box of sorts for the rear lighting. It's mounted under the rear left corner of the box. Where everything plugs in. Idk if that's a module or just a terminal board type thing? If it's a module, and it's bad, could that cause feedback through the whole system?
 
#25 ·
Do you know the steps to troubleshooting anything? If you install something, and problem occurs, it was installed incorrectly, bad part, wrong part, etc... switch back to original and test again. If with the original lamps same issue, you caused something to go bad, or you fall into that Itty bitty tiny ass % of people who do something the same exact time another part fails. Being it's electrical I feel your forgetting to mention something or don't realize something you've done. Did you tug hard on the wires, not the connector. Did you try to pull more slack up from underneath? Did you cut anything? Did you mess with anything else in the process of the install? If you put both factory lamps back in and still an issue and you have front LED lamps, put regular incandescent in the front aswell. Test again. Try ordering a different lamp from different vendor. The BCM has nothing to do with your issue. Zero I promise. I would say flasher relay is fine aswell since obviously you have lights flashing. Which tells me you have lamps reversed and your back feeding a different socket. If you can't rotate the LED lamp because of socket, you got the wrong lamp
 
#26 ·
lol thanks but I do know how to troubleshoot. Yeah I agree it's not the bcm after looking at the wiring diagrams again. It shows the left and right signal lights going to bcm but other pages show more connections so I was looking at bcm off of that first diagram. The only thing I've done is disconnect the harness connections in the rear and swap reverse LEDs in. I've tried putting things back to stock, bulbs are correct, sockets won't swap, it was probably like this way before I swapped I just didn't notice. I'm gonna check for some splices but if I don't find anything I'll probably just swap the pins for backup and flashers at the rear connectors.