Electrical short, fuse blowing

[fatryan 5,000+ posts]

Just a few weeks ago my power locks stopped working. when i finally got to look at the a couple days ago, i saw the fuse blew. i havent touched anything on my blazer in months, it just came outta nowhere. but within the last few months (for no apparent reason), i started getting a leak between the door and body of the car. and it was leaking onto the switches. the rubber seals are in perfect condition, so i dont know why it would even leak. but either way i think thats the problem. i replaced the fuse and it worked for a while until today it blew again. how do i find out where the short is? i think its in the switch, but i dont want to go buying a new switch if its not the problem.

Click to read more...

 

[fatryan 5,000+ posts]

any1?

 

[azbass 5,000+ posts]

there is a short to ground some where. also if water was leaking in to teh switches there may be your problem there.

 

[Arawak420 10+ year member]

did you use the same size fuse? maybe try a higher amp fuse?

 

[azbass 5,000+ posts]

higher fuse wont help.

 

[fatryan 5,000+ posts]

there is a short to ground some where. also if water was leaking in to teh switches there may be your problem there.

well im pretty sure it is the water that damaged it, but how can i be sure without dropping big $ on a new switch?

 

[fatryan 5,000+ posts]

did you use the same size fuse? maybe try a higher amp fuse?

nah, i replaced it with the same size fuse as it came with...15amp

 

[fatryan 5,000+ posts]

i replaced the fuse again and it blew again. any1 got any ideas? theres got to be a way to test this

 

[justinschmiidt 10+ year member]

if you park outside or anything it could just be moisture build up and not water *technically* at all.

 

[helotaxi 5,000+ posts]

If you look at where the door actually seals to the body of the car, the seal is on the very edge of the door closest to the car body. The majority of the door itself is outside the seal. There are drain holes in the bottom of the door that can allow moisture into the door during very wet conditions. Obviouslt where there is water and electricity both present there will be corrosion and that is probably what killed the switch.

As far as replacing the switch, try eBay and junkyards.

 

[fatryan 5,000+ posts]

If you look at where the door actually seals to the body of the car, the seal is on the very edge of the door closest to the car body. The majority of the door itself is outside the seal. There are drain holes in the bottom of the door that can allow moisture into the door during very wet conditions. Obviouslt where there is water and electricity both present there will be corrosion and that is probably what killed the switch.
As far as replacing the switch, try eBay and junkyards.

well do u know if theres any way to make sure its the switch thats shorting everything out?

 

[helotaxi 5,000+ posts]

Not off the top of my head, sorry...

 

[Hydrastas 10+ year member]

double check the wiring, use a voltameter, check each wire running to the switch. If you wanted to be positive, take out the switch and test it in another vehicle.

 

[fatryan 5,000+ posts]

double check the wiring, use a voltameter, check each wire running to the switch. If you wanted to be positive, take out the switch and test it in another vehicle.

sadly i dont have a spare blazer to test it in, lol.
what do i need to do to check the wireing with my DMM? like, am i looking for a V reading, resistance, what?

 

[Hydrastas 10+ year member]

with the power on, check the voltage of each wire, if any are not normal or have a ground when they shouldn't, then that wire needs to be checked for damages.