[Dougbp]

I have a 92 968 Cab.  Battery kept running down. So I disconnected the ground from the battery for several days.

When I checked the amp draw across the battery ground and ground cable several days later I noticed a spark, so I am thinking that I must have a pretty good short to cause that or I absolutely do not know what I am doing and that is a given.  Electrical is a mystery to me. 

 

On the Multi-meter (normal 4 port configuration) I have the leads in the Com and 10A ports:

I set the multi-meter to the 10A switch and I get a reading of 0.11 amp.  I am thinking that is a hell of a draw.  I repeated the test a number of times and the values did not change.  0.11.  Then I noticed if I held the probes on for more than 5-6 seconds the draw went down to 0.01 at the 10A setting.  Repeated numerous times.

 

So I wonder if when I connect the leads to the ground cable and battery ground and get the spark, is there enough voltage to wake something up momentarily and then it goes back to sleep.  Is that normal?

Don't see any lights on, removed the face plate to the aftermarket stereo, keys are not in the ignition.  

 

Plus the fact that the amps drop down to 10 MA (.01 A) seems like a stupid number for a 1992 cab.

 

So as long as I have entered the adjective "stupid" into the equation, please feel freee to tell me what aI am doing wrong?

 

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[MCL968]

Hi Doug,

 

I can't speak to your question regarding the change in draw once the battery is connected, but I would offer some advice.

 

First, you can create the illusion of parasitic draw by having the door open, the trunk open, or the hood light activated when you do the test. Any of those things will make the ground lead spark when reattached.

 

Second, the best way to determine where the draw is located is by pulling fuses and then checking the spark at the battery terminal. Pull one fuse at a time and see when the sparking diminishes.

 

Finally, the ignition switches on these cars are wearing out and producing some very strange symptoms because there are several accessory circuits in the switch. I replaced mine (there is a thread in here on the process) and many strange problems disappeared.

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[unknown4u]

The original alarm will trigger your lights. After a few seconds it goes into 'sleepmode'. But perhaps your original alarmsystem is not properly disconnected in the past and still active but does not show it by light up the hazardlightd.

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[John]

11 ma is in the right range for static drain (94,6sp coupe, don't know about TIPs). Whenever I attach the ground cable to the battery, I too get a small spark. So your results appear normal. That 11 ma represents the clock and little else. Kind of rules out the usual suspects: under hood, glove box, and hatch lights. Agree on the ignition switch as a possible. Is the car locked prior to when you discover the battery has been discharged? That could point to the alarm sys.

How old is the battery, have you had it tested?

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[Dougbp]

It was an unknown battery - so I replaced with a new one.  I will check for alarm never paid any attention to lights, plus take a jaundiced look at the ignition switch, it feels pretty sketchy.  Car is in my garage and unlocked.  I will check these this weekend.  

Most burning issue I need to get fixed now is the windshield wipers are inop.  That is the rest of the weeks project.  Blown fuse replaced but that didn't fix it.  So now to look at switch.

Thanks for the input, 

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[MLB]

My wipers are also inoperative, and blowing the fuse.

Will be eager to know how your fix is going. It seems I need to take apart the wiper motor, but I haven't even been able to extract it from the car yet

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