parking lamps problem

[Jeffcu]

Make

Pontiac

Model

Grand Prix

Year

2006

Miles

178k

Engine

3.8L v6

Hello.
The fuse for the parking lamps died so i attempted putting a new fuse of the same rating in and it immediately failed. probing the space for the fuse i have 14v on one side and -0.6v on the other.
I'm assuming there is a short to ground somewhere in the system but i have no idea where to even begin looking.

Jeff

 

[grcauto]

Change the bad bulb.

 

[billr]

Are these incandescent bulbs? Those rarely (never?) fail shorted. I will look for schematics later. so we can make an attempt to find the short.

 

[grcauto]

Are these incandescent bulbs? Those rarely (never?) fail shorted. I will look for schematics later. so we can make an attempt to find the short.

You haven't done much of this work or you wouldn't say that. I'll bet it's a bulb or bulb socket.

 

[billr]

So, if it could be a bulb socket, why throw a bulb at it; and which one would you suggest, all of them?

Jeff, I couldn't find a schematic, but may still be able to help. Does the fuse blow even if your are not trying to turn any lights on? When it is in the "fuse blow" mode, read resistance to ground on that fuse socket that has -0.6V; report what you get. Without a schematic, the next step would be to remove all bulbs, inspecting sockets and wiring while doing so, and see if that resistance from fuse to ground changes significantly (like goes towards infinity). And you can check each of the bulbs for resistance, see if one is shorted...

 

[grcauto]

So, if it could be a bulb socket, why throw a bulb at it; and which one would you suggest, all of them?

Jeff, I couldn't find a schematic, but may still be able to help. Does the fuse blow even if your are not trying to turn any lights on? When it is in the "fuse blow" mode, read resistance to ground on that fuse socket that has -0.6V; report what you get. Without a schematic, the next step would be to remove all bulbs, inspecting sockets and wiring while doing so, and see if that resistance from fuse to ground changes significantly (like goes towards infinity). And you can check each of the bulbs for resistance, see if one is shorted...

I suggest he start taking bulbs out until it quits blowing the fuse. At that point inspect the socket and bulb. Who knows he may get the right one on his first try.

 

[nickb2]

Hope this helps

 

[billr]

It's a good start, but the OP has a problem with parking lights. Are those on the "external lights circuit" branch? Let's wait to see if the OP returns before I bug you for more schematics.

OP, what is the label and value for the fuse that is blowing? Knowing that will assure we are digging into the correct circuit.

 

[nickb2]

Dang it, maybe I got a thread mixed up, ok here goes for parking, NOT back up. sorry.

Thank you billr for catching that.

 

[grcauto]

Dang it, maybe I got a thread mixed up, ok here goes for parking, NOT back up. sorry.

Thank you billr for catching that.

Happens all to often with me as well.