I installed Hella's inside the grill like so many others. The one thing I did differently is to use the power wire from the radio to power up the lights (still using the relay, but instead of being able to turn on the lights at any given time, I wired it so the lights could only be turned on when the truck is turned on... in other words, only when the radio is rec'ing power).

It started two weeks ago. I got a call from my father saying that the grill lights were on and he couldn't turn them off. I thought he just was crazy because I asked him if the truck was running and he confirmed it wasn't.

I didn't have any problems until yesterday. Even with the key out of the ignition, the radio would sometimes turn on, therefore the lights would be lit up.

Today while at work, a co-worker told me the lights were on again, so I went to my truck and disconnected the relay that goes with the Hella's. After doing this, the radio doesn't power up unless the key is in the ignition like it's supposed to be.

At first I thought it could be a melted fuse holder in the lighting system, but even at that point, it shouldn't route any power to the radio without the key in the truck.

So basically, I can only think of the relay itself as the culprit. Since it's been raining and too cold, I haven't been able to go investigate.

Does the relay malfunctioning make sense? Am I overlooking something else?

 

So my hunch was right.... The relay was defective, causing the circuit to be complete, but it wasn't a constant circuit.

I opened it up and this is what I found:



$4.99 later, and my lights work like they should.

 

Glad you figured it out. Happened to my lights when I first got them. Ended up getting pulled over because I hit a bump and they "lit up" a cop.

 

easy fix, nice. I had an electrical problem in my Bronco that kept blowing a fuse and I'd have no rear running lights and no speedometer lights, nothing. I took a day off from work and found live wires from the previous owner that were shorting out. Ripped that **** out and no more blown fuses lol

 

next time , pay the extra money and buy a genuine BOSCH relay

they are waterproof and you will never suffer that problem again

 

I had a hard time finding any store that had the relay to begin with. All the parts stores carried the 5-prong relay, but this is a 4-prong.

 

glad you got it figured out.
in all my years of electrical i never had a relay go bad.... even the cheap ones... but there can always be a bad one in the batch.

 

can you post a picture of that relay , i have the bosch schematics

bosch does make 4 prong relays , but it depends on the shape of the relay