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rickeyddman

By rickeyddman
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rickeyddman New Member

rickeyddman

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I have a 2001 Z71 bought it about 2 years ago. Noticed shortly after a low but constant drain on the battery, about .5-.75 amperes. which equals dead battery in few days of inactivity. After 2 years of trying to track it down and baffling local mechanics I pulled every fuse one by one to find where the source was.

 

I can have every other fuse pulled but the ATC and still have the drain. When i pull the ATC fuse the amp drain increases to 1.0A for a few seconds then down to .1A which I assume is as close to zero as its going to get. When I replace the fuse I hear a click from under the truck (transfer case I assume) and get a jump to 1.25A then falls off to .75A after a few seconds and remains there.

 

Question: Is this a typical characteristic of a bad dash switch or do I have sensor issues or the encoder problems I keep reading about? How do I determine the source without just dropping a wad of cash on all the above?

bill190 Enthusiast

bill190

Posted
Posted

If no one else knows a specific solution for this....

 

My way would cost quite a bit. That is to first get the factory wiring diagrams with the service manual set, then see what all is on this circuit. But the factory service manual set is not cheap!

 

Then you kind of need to be an electronic type to understand the wiring diagrams, so if you're not an electronic type, this might look like Greek to you...

 

Anyway I would get the factory service manual set and look at the wiring diagrams to see what all is on that particular circuit. And WHERE each device/switch/whatever is located on the truck.

 

Then learn how each component is supposed to operate, try removing different components and see if this reduces the amperage draw. BUT this can be tricky! There might be a faulty switch powering something and you remove that "something" and the amperage draw decreases!

 

So you conclude that "something" is the problem, spend $200 to get a new something, install it and same problem. Then learn all along it was the switch controlling that something which was the problem - then get the new switch.

 

So it is important when troubleshooting this stuff to also understand how everything should operate, then try different things to find the EXACT problem. And be able to test each device to see if it is working ok or not.

rickeyddman New Member

rickeyddman

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Posted

I can read schematics so that wouldnt scare me. Before I do all that I'll try a switch from a salvage truck before I purchase all those new parts and maybe that will fix it for the short term. If that doesnt I will take it back to the mechanic I trust the most and show him what I have found and let him trace from there. just was hoping someone else might recognize the symptoms from a previous issue of their own.

 

Anyone?

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