Hey everyone love the forum and it always helps. And finally had something happen that isn’t coming up. Here goes I have a 1998 sport Cherokee. The issue is and only issue is both side marker lights have gone out completely. First thing I did was check both bulbs. Also everything in and out is super bright LEDs and I haven’t messed with any of the original wiring. I then check the sockets the power has 12v and the ground has like .08. In the wiring and the socket. When I hit my blinker the ground alternates with the blinker. If I with my power probe probe the power wire and give it 12v the socket works and turns the light on. So then I visually inspected to be safe all the wiring up to where the headlight wiring harness plugs in to main harness didn’t test here since everything works and like I said had ground and power at socket. Looked beautiful and cleaned it anyway. Right up above that is two chassis grounds that I cleaned but looked fine. I double checked my led flasher relay but it’s good. I am not a big electrical guy mainly mechanical. I don’t have ohm reader just a power probe. I checked every bulb to make sure everything was bright and functioning. So I am completely lost. If I had a loss of power or ground I wouldn’t have anything coming to or out of socket right? My next thing is to switch out the headlight switch. But can’t find anything about this problem. All other posts are about one side of the jeep where as mine is strictly the side marker lights on both sides. Also sorry fuses are good and not blowing. Also tried switching out the led to a regular bulb no dice. Please help because I love my side marker lights and want to restore the old beauty. Thanks everyone be safe.

 

The side markers don't have a ground, they're strung between the running lights & blinkers. That's why when the running lights are on, they flash out of synch. Most LED's are polarity sensitive so won't work as intended connected like that.
Personally, I'd put the old bulbs back, because I think XJ sidemarkers are, if anything, too bright anyway.

The alternatives are:-
if you're not fussed about the blinker function, disconnect that wire & replace it with a ground
There are now LED's that aren't sensitive, which, presumably, work in that application, but they are more expensive
Before there were such things, there was a work round using 2 relays, but I can't remember the details - there's probably a thread somewhere here.

Just noticed you say swapping back the old bulbs doesn't fix the problem - & it is odd that they both failed. However, it's just a socket connected to two circuits which are known to be OK (i.e. the position lights & blinkers) so it must be the bulbs, sockets or wires & from what you've already checked, does seem like a wiring issue. Now I assume the sockets have pigtails (I wouldn't know 'cos export models don't have sidemarkers (one of mine does - but that's another story, & they're not OEM) so for the cost involved you might as well just get new ones.

 

can you change the lights and sockets?

 

There was a thread somewhere about modifying the side markers to blink in sync with the turn signals. Just can't find it at the moment.

 

I'm pretty sure the socket is a 90* twist fit in the back of the marker housing.

 

You're right it involves 2 5-pin relays with 87 & 87a X-wired - but I can't even remember whether I saw it on this forum. Curiously, I was trying to find it over Christmas, without success..