Tater114

Hi Guys,


Have 04 Cherokee, daily driver. The right Brake light works until you turn the head lights on, then only the right rear brake light doesn't work. Everything else works like its supposed too. Changed the bulb and the turn signal switch but neither helped. Fixing to replace Headlight switch but I don't think that's it either. Any Ideals before I spend too much for nothing??


Thanks, any help welcome!

dave1123

Sounds to me like a ground problem in the taillight socket or housing. Not an uncommon problem. The plastic tends to melt and lose contact with the circuit clips.

rizmonkey

melted socket contact. Remove the bulb, carefully pry up the contact with a small flat head screwdriver. fold a small peice of aluminum foil into a little square and put it under the contact. replace bulb and it should fix the problem. The contact has a tendency to melt into the plastic which breaks the electrical conection to the bulb. The aluminum foil repairs the connection. Easy 5 minute fix.

RIZ

Tater114

Well first I miss spoke, headlight switch is built into wiper switch so that is why its called multi-switch...duh on my part, my bad. Anyway, thank you for quick reply. I've messed with it some since first post and not a ground problem or I made the problem worse. Now showing short on taillight contact where it wasn't before. Might have been shorting but not noticeable fully until now. So searching for a short but haven't found one as of now. Any recipes for finding shorts?? Thanks guys!!

dave1123

Wait! What? On the Grand Cherokee, the headlight switch is the turn signal switch and dash and interior light switch as well. The wiper switch also controls the washers. There is nothing about lighting on the wiper stalk.

Also, a short will blow fuses. An OPEN circuit causes lights to not function. If you used the aluminum foil trick, are you sure you didn't cross 2 contacts?

What happens with the taillight socket is the ground terminal looses contact because of the plastic melting. The brakelight then grounds thru the taillight bulb. When you turn on the headlights, the brake light gets power when you step on the brake but can't light because it's already getting power from the taillight circuit. It's a higher wattage bulb so it won't light up when it's being powered thru the taillight bulb. Go get another taillight socket from the JY! I'm assuming we're talking about the grey insert that holds the bulb, right?

Tater114

Well, actually is was talking about the short showing in the housing not the socket, but in regards to this, I was tracing the harness behind the interior panels and had everything apart (not finding the problem I was looking for), but was running out of time for my weekend, so put everything back together just to find out, that for now anyway, everything is working like its supposed to. I'm guessing that when I was moving the harness around that its now not rubbing where ever the short was? And one last thing that I noticed, all three sockets are the same along with the bulbs (3157's), only the housing only makes connections at two of the contacts for two of the lights and all three contacts for the brake and turn signal light. Thanks for all the help!

dave1123

Yeah, I noticed that too. I suppose you could swap bulb sockets with a reverse socket to find out if it's the socket or not. I'll have to remember that.