deutschman

I have a parasitic draw issue. If we don't drive the car for a day it wont start.
It has a new GM up rated alternator and the battery had a full charge when I did these tests at above 12v (almost 13v).
Tested inline with the ground terminal of the battery at 10 milliamps.
-Dome light fuse draws .050 milliamps (no change if the dome light switch is in the off or on when door open position, and no change when I manually push the door buttons in the jam).
-Cig lighter fuse draws .750 milliamps (easy fix just leave the fuse out for now. I don't smoke.)
-EFI fuse draws .040-.050 milliamps

My question is is it normal for the EFI system to draw .050 milliamps when the car is off, and is it normal for the dome light to draw the same amount of amps?
I assume the dome light might have a bad ground, or the switch in the light is all dirty and grounding out?
Not sure why the EFI system would be pulling amps unless its associated with the ECU which might always draw a small amount of power. Bad engine or ECU ground?

Thanks for the help guys.

millball

Faulty ignition switch??

coryc85

Are you sure the switch is all the way back and not in the ACC position? Anytime somebody drives my truck, they almost always leave the key in the ACC position because the ignition is so worn out the key will remove in any position. Certainly that Cig fuse is a lot of current, is there an aftermarket stereo in the car? Whoever installed it might have tapped off the cig wire, which might explain the draw there.

deutschman

Good call on the ignition switch. Could very well be. I can start my truck with just about anything that fits in the ignition lol
maybe the radio is tapped off the cig lighter. It does have an Aloine head unit in it.

Thanks for the help!
Ima pull that radio out.

atcfixer

iTrader: (1)

EFI fuse in the newer trucks does supply power to the ECU. Seems the power draw for the EFI fuse is fairly accetable, a bit lower would be nice, but I've never tested one to see what they typically draw.

Dome fuse on a 94 T100 (similar era atleast) also runs the clock. The clock probably draws a tiny amount to keep the time memory, the display should go out with the key off.
Cig Fuse goes to cig lighter AND clock (different wire than the other one). I suspect one is powered all the time (aka memory) and the other is only on when the ignition is on acc or on.
Looks like EFI fuse is ECU, EFI main relay, Circuit Opening Relay (COR), AC idle up VSV, and finally Fuel Pump (with EFI relay and COR closed).

I the draw could very well be the radio installed incorrectly (always powered), but you'd probably already know that because you'd have to turn it off every time you get out.

Good luck digging into it!

Co_94_PU

iTrader: (-1)

Your ignition switch is faulty, you shouldn't have power thru the cig fuse unless the key is on.