Trying to locate parasitic drain

kyman · 12-29-2012, 09:35 PM

About to lose my mind and patience looking for the cause of a parasitic drain on son's 2002 ZX5. Took clamp off negative battery post and put test light in line between post and clamp. Light was lit. Pulled all the fuses in passenger compartment and test light stayed lit. Thought I had it when I pulled the under hood 40 amp fuse that goes to passenger compartment box and light went out. Tried several times and light went out every time. Checked and did not see any wires grounded between the 2 fuse boxes. Now light stays lit when I pull the 40 amp fuse. Arrgh
As a side note, radio operates without keys in ignition. Looks to be factory installed 6006 tuner. Is this normal?
Have pulled out a bunch of the little hair I had left.
Any advice would be much appreciated.

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Covmister · 12-29-2012, 11:40 PM

i cant really comment on the radio being on when the keys are out but a good way to test the parasitic drain is to use a dmm set to amps dc, take off the neg battery cable and attach the red lead to the bat neg and the black lead to the neg cable. ideally you should see about 50 ma or less, i do know that our fords do draw a bit more because the PATS system takes a bit longer to tell all the systems to "sleep" try keeping all doors open but trick the car into thinking they are shut by closing the strikers, then wait for the amp draw to be around 50 ma or wait 45 min or so then watch the dmm and start flipping switches....defrost...headlight....radio....glovebox open close...ect. this will help locate the draw easier because the car still thinks its asleep as long as you keep the keys out of the ignition...when you find the cause of the draw you will notice the draw drops....case in point glove box light is on...take bulb out draw lowers....radio does the same...its a pita to find parasitic draw but it can be done. good luck i am not electric god but i do know a thing or two about a thing or two

my_beautious_ZX3 · 12-29-2012, 11:50 PM

that's normal for the radio - try it again and you'll notice that it displays "1 Hour" when you turn it on with the key off.

A test light is okay for basic live/dead tests, but if you can get your hands on a digital multimeter, that will tell us more. If you search the forum archives, you'll find some typical amp readings that other users have observed on their Focii.

Whether you're using a test light or ammeter, note that the vehicle electronics will reboot and enter a state of high activity for several minutes after they are re-energized. Therefore, ignore the initial tester behavior, and then make your observations after the electronics have settled into their steady-state operation, in the sub-amp range. If you're seeing greater than an amp, then systematically pull fuses in both boxes. Don't turn on any high-load accessories or you'll probably blow the fuse on your multimeter.

kyman · 12-31-2012, 03:40 PM

Put multi meter in line. Showed 180ma. Drops down to 30ma when under hood fuse going to ignition switch, starter is pulled. Should I get a wiring diagram and trace the wires or any easier ideas where to start?

***whynotthinkwhynot*** · 12-31-2012, 05:41 PM

Is your car having problems starting after sitting for a few days or something?

It sounds like you have a bad ignition switch since you dropped down to 30 ma after pulling the ignition hot. The stereo should pull a little even with the key off for memory, and some of the other electronics might also. Nothing that would keep you from starting after a week of sitting.

kyman · 12-31-2012, 06:13 PM

Whynotthinkwhynot, Car will not start after sitting several days. Do you know where I can find directions for replacing the switch? I work at the Kentucky Truck Plant and can get it on our system but am off til Jan 03. Hoping to get it fixed by then.

***whynotthinkwhynot*** · 01-01-2013, 09:08 AM

Quote:

Originally Posted by kyman

Whynotthinkwhynot, Car will not start after sitting several days. Do you know where I can find directions for replacing the switch? I work at the Kentucky Truck Plant and can get it on our system but am off til Jan 03. Hoping to get it fixed by then.

I'm sorry, I don't personally, but hopefully someone with an All-Data subscription can give you more information. We don't currently have a How-To on this procedure. We have lots of stuff for the ignition lock cylinder, but nothing for the ignition switch. If you can make one, provide pics, etc, of your experience, that would help. It shouldn't be too hard. The ignition switch is located on the top of the steering column just past the dash towards the floor. In the past I've had to drop the bolts that hold the steering column in place, unplug the switch, unbolt the switch, and then put it all back together. You may want to unplug the switch first, then drop the column to remove to prevent stressing the connector. OF course, inspect everything for signs of wiring damage, etc.

Covmister · 12-31-2012, 07:08 PM

Well if it drops that much after that fuse is pulled sounds like that may be the source of your issue....ignition switch....

Covmister · 01-01-2013, 05:26 PM

To the original poster of this thread; message me your email and the year make model and engine (sohc or dihc) and I'll get it from all data tomorrow at work