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Discussion Starter #1
So after having my batteries drain over a 2 day period ,I started to look at the battery drain and I have a .5 amp continuous on the gem module. I have pulled interior lights and brake pedal switch connector and no change . Do these modules go bad internally? We did have a rotted windshield frame so it could of had water get to it.
 

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It's possible that the GEM has been damaged by water intrusion. If you do replace the GEM, you'll need to get the replacement programmed to match the old one.

A maximum 50mA draw with all the modules asleep is normal. That's 1/10 of what you're seeing. Are you sure that you've checked with modules asleep? The way to do that is to leave the door open till the interior lights go off, then check the draw. If you interrupt power connecting your meter, the modules will wake up and draw more power.
 

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Discussion Starter #3
I had the door shut and the reading never changed after more than 1/2 hr.
 

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After a exhaustive search for this drain on my batteries ,it turns out I have one bad battery and was drawing the other one down over nite. I brought both batteries and alternator and had them load tested at a chain store and both batteries showed good . I pulled the fuse box,Gem module out to look for corrosion/water marks and it was clean . It wasn't until my Dad suggested trying to start the truck off each battery individually to load test them did I find it. So check your batteries even when they say they are good from a parts store. So hopefully that's the end of my issues.
 
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Thanks for closing the loop on this.
Batteries always need to be load tested individually. Your Dad's starter test was a quick and dirty way to do that. Good suggestion.
 

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Discussion Starter #6
That's the weird thing, I brought each battery in and put them on the counter of the parts store. Both tested good.
 

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That's the weird thing, I brought each battery in and put them on the counter of the parts store. Both tested good.

It happens. Even the fancy battery tester that Ford requires us to use passes batteries that for whatever reason fail to hold a charge.
 
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