I brought my 2000 F150 to a shop to have the intake manifold gasket replaced. When I got it back, I noticed my light bar didn't work anymore. Its a 55" curved LED light bar. When I press the switch, it quickly flashes on then turns off, even though the switch is still on, and the light on the switch is green. I checked the wires and they're all plugged in as they were before I brought it to the shop.

Any ideas on what it could be?

 

Did you have issues with the bar before you took it to the shop?

 

Sorry....missed your last sentence about it working before.

 

I was only asking because the last time I took mine into a shop, they had to disconnect my battery, when they connected everything up again, they mistakenly hooked my power wire to the ground (-) on the battery and not the power (+)...it took me a while to figure that one out.

 

Well, you know all the LED chips still work if they're flashing briefly. That's a good thing. I'd contact the manufacturer of the light bar and ask for a procedure to reset it. All good quality manufacturers will offer assistance. Cheaper ones usually don't. AAMOF, we usually can't even find them when there's a problem.

Hope it all works out for you!

 

I would unplug the bar, then use 2 jumper wires to connect if directly to the battery to see if it works properly. Then check your lighting harness relay (if you have one) with a continuity detector. If those all work then check all the connections in your harness. Finding wiring gremlins is a process of elimination.

 

Replace the $3 relay that I hope you're using. at least tap on it or take the cover off and clean the contacts.

 

First this.

Then this if it's working.

Could be the ground on the relay too. Unknown what your setup actually looks like and unknown what they did, but it's likely just a connectivity problem.

 

55" light bar? You sure you don't mean 55"

1) You are using an inexpensive light bar if it's in fact advertised as 55" (rigid, baja, putco, all well known brands only advertise as 54" so if it's advertised as 55" tells me it's a lower quality bar and SOMETHING got hooked up wrong at the shop and it fried something to the point where now all she's doing is flashing real fast before something overloads (check to make sure it's not wired backwards). Quality light bars have protection so if you hook them up backwards, nothing happens. Low quality bars skip this (that's why it's cheap). I've seen this with LED headlight kits on the cheap end where they get hooked up wrong and give a quick FLASH and that's all she wrote.

2) If it's wired the right way, ask the shop if they disconnected anything HOPEFULLY they admit to that and possibly as I said, it got wired backwards at some point and something fried inside

3) What brand bar is this???

4) Smell it... anything smell BURNED???

5) Anything LOOK burned, take a close look at the diodes

6) Do ALL the diodes flash real fast???

7) Check the relay as someone else said

You're in the wrong section btw, this is the offroad section. You'd have better results in the lighting section but we'll see if we can help ya here.

 

I'm guessing the shop wired it incorrectly.