Engine/Transmission (1998.5 - 2002) 50 Amp Battery Fuse ?

[TShively]

In the power distribution box there is a 50 amp battery fuse, I was wondering what this powers? Iam thinking that it might be a keep alive power to all the modules. The problem is my friend has a 2001 and there is a drain on the batteries and when that fuse is pulled the drain is gone we didnt have a multimeter to see exactly how much of a draw there was we were just using a test light. Any ideas, thanks for the help!!

 

[CCBrady]

TShively,

First, lose the test light it is of no use to you for this kind of troubleshooting and get yourself a good DMM that has DCA fucntion, settings for 1-2 A and one for 10 A is best. (Note; good does not equal expensive).

You are correct that the 50A fuse pwrs just about every thing, it pwrs the junction block that distributes power to the truck. To do a pwr draw test you use the amp funtion on the meter. I think these trucks with nothing on is about 0. 3A. One thing to remember is if you have an alarm system use a jumper wire between the battery post and cable when you are setting up for the test. If you don't when you hook up you meter the alarm system will flash your light and this will blow the fuses in your meter and the fuses in most meters are a little hard to get and spendy. After you are all set up remove the jumper.

Good Luck, Chris