battery draw

[redboost10]

so i have had a battery draw for a while now. small draw that wears the batteries down if it sits longer than a week. finally got around to looking for it and it turns out its fuse 15 from the underdash fuse panel. when i remove this fuse the testlight turns off.

15
5A
Generic Electronic Module (GEM),
Powertrain Control Module (PCM),
Anti-lock Brake System (ABS) Module,
Brake Shift Interlock, Speed Control

so this is what that fuse controls....anyone have this problem and/or any hints on where to go from here?

thanks guys

[redboost10]

oh i should let you guys know that this truck is an early 99, and i did the resistor mod to the idm and swapped the old pcm for a pmt2 pcm.

[driximus]

If this started after you did your mods go back and undo them 1 at a time and check for the draw.

[35thls1ss19]

i been chasing the same thing all winter! Same fuse number 15 was causign my draw. Warm weather came and it stopped? I haven't checks with my multi meter but the batteries do not die anymore. Only thing i did do which i read might be a problem was put a ground wire to my pcm. But i have a dp, i heard that the computer are not grounded very well. I did that and cleaned my terminals really good and no problem since.

What kind of draw you getting? i was getting .10 with the 5a fuse in once i pulled it it would drop to .02 which is where its suppose to be.

[redboost10]

this was happening before the mods as well. i didnt check the draw, just removed the ground terminals, put the testlight on the ground and started pulling fuses. how did you ground the pcm, ill try that, ill make a small ground for it underneath the dash. clean the terminals up good and see what happens.

so did you ground from the inside or did you ground fron the screw that holds in the connector?

[redboost10]

alright so i unplugged the pcm, still has a draw (testlight is still on). so then i mess around with the brake pedal sensor, i unplugged it and it still has a draw, so i plugged it back in and pressed the brake pedal and it got brighter. then let go of the brake pedal and the testlight dimmed. so not the brakes. anything else to check for fuse 15?

[redboost10]

ok pulled down the fuse box, unplugged the gem connectors. at first i unplugged them one at a time and the testlight was still on. so then i unplugged them both at the same time and it went off. does that mean a bad gem?

[bad_blue_oval]

you need to put a meter on it and measure milliamps. a test light is not accurate enough. Also the computer enough time to go into sleep mode after you key off and shut the door.

[redboost10]

ive been sitting in the truck with the doors shut doing all this looking through the window at the test light. ill get a meter and do it that way.

[bad_blue_oval]

How much longer than a week does it take to completely drain them? Did you fully charge and test each battery while disconnected from the truck?