Mechanics

PROBLEMS DRAINING

2003 Chrysler Concorde • 6 cylinder FWD Automatic • 100,000 miles

Battery draining. Tested it. Found a reading of 1.6-2.0 ohms. Pulled all fuses no change in readings. When going from a gear to p the ring gets stuck on the r and sometimes it takes awhile for it to get on the p. Why is it sticking on the r
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Deaner
March 25, 2011.




Could be a problem with the range indicator switch assembly but that shouldn't cause a drain when the ignition switch is off. How are you measuring the drain? That is normally done in amps, not ohms.


Caradiodoc
Mar 25, 2011.
I pulled the battery put meter on ohms like told to. He said it should read above fifty and if it was less it had a drain and start pulling fuses to find draw. Had a prong on each terminal one on - one on +
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Tiny
Deaner
Mar 26, 2011.
Something is way screwed up with that method. Ohms means nothing in this case. You're going to be reading computer memory circuits that are trying to charge up, and other circuits that are being turned on by a computer and draining the battery won't even BE turned on since the little battery in your meter isn't strong enough to run all those computers. Even if you did that on an older car with no computers, doing the math, 2 ohms would mean there would be over 6 amps of current flow. That would be the same as leaving one high beam head light on. There is absolutely no way an ohm meter is going to give you any type of accurate reading from the battery cables. You must do any testing for a current drain with an ammeter inserted in the circuit. You have an additional problem of computers that have to time out and go to "sleep mode". They can draw a total of around three amps for up to 20 minutes after stopping the engine. Any testing done during that 20 minutes is irrelevant. After that 20 minutes anything you do to temporarily break the circuit will wake the computers up again and start that 20 minute cycle all over. That includes even switching ranges on the meter. I'm working on a drawing that will help explain how to test for a drain because other people have run into the same problem. I'll post that when it's finished, hopefully in a few hours. In the meantime, you're going to need an ammeter that can measure up to 2 amps, (2000 milliamps), and it should have a 10 amp scale too, and you'll need a jumper wire that can be attached to the battery post on one end and the cable clamp on the other end. Clips for your meter leads will be real helpful too so you don't have to hold onto them with two hands, leaving you to pull fuses with your, ... Uhm, ... Other hand!


Caradiodoc
Mar 26, 2011.
Step 1: Remove either battery cable.

Step 2: Connect a jumper wire between the battery post and cable. The computers that wait to go to sleep mode will take at least 20 minutes to time out. No testing can be done until then.

Step 3: While waiting, connect the ammeter so the leads will not fall off. Later, if either lead falls off while the jumper wire is disconnected, or if you switch the meter to a different scale, the circuit will be broken which will wake up the computers for another 20 minutes. They can easily draw enough current to blow the internal meter fuse when the lead is reconnected. It is safest to disconnect the negative battery cable. If the positive cable is disconnected, as shown here, be careful to not let the cable, jumper wire, or meter lead touch any metal part or the car body. A vise grip pliers works well for holding one meter lead to the battery post. A second clip lead will do a good job of holding the second lead to the battery cable. Another solution, if you only have small clip leads, is to drill a small hole in the battery post and drive in a screw to connect the clip lead to.

Step 4: Until the computers go to sleep, the high current will flow through the easiest path which is the clip lead. That will protect the meter's internal fuse from blowing. Start with the meter on the 2 amp scale. The clip lead can be disconnected after a minimum of 20 minutes. By that time the current will have decreased to a level that can be safely measured by the meter. If the current reading is greater than 0.2 amps, begin removing fuses or disconnecting plugs until the value goes down. When it does you found the circuit that needs further diagnosis.

Step 5: When the current reading is less than 0.2 amps, you can switch to the next lower scale on the meter for more accuracy. That is most commonly the 200 milliamp scale. All ammeters use a range switch that breaks the circuit before it connects to the next contact when switching scales. Doing that will wake the computers up again. To prevent that, first reconnect the jumper wire, then you can switch the meter to the lower scale. The jumper wire can be removed again right after the range is switched.

Step 6: Unless the manufacturer specifies something different, 35 milliamps is the industry accepted maximum allowable current. If you find more than that, again remove fuses to determine the circuit with the problem.


Caradiodoc
Mar 27, 2011.

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