Mechanics

CHRYSLER INTREPID BATTERY PROBLEM

2004 Chrysler Intrepid • 245,000 miles

In the last week I have put three different batteries in my car and they keep dying. The alternator is working I have had it checked. The ground cable seems to have a good connection and so does the positive. Is there anyone else who has had this problem or may know what is causing this. When I try to start it, it will turn over once then start ticking or just go straight to ticking, and this happens a day after I have charged it and put a good charge on it. Thank you.
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Leggatron
February 5, 2013.




Sounds like you have something draining the battery. Replacing it isn't going to stop that. The test that needs to be done is called the "ignition-off draw" test. This used to be real easy to perform but now we have unnecessarily complicated computers that need up to 20 minutes to go to "sleep" mode. Performing the ignition-off draw test gets a little more complicated.

You can start by checking for glove box and under-hood lights that aren't turning off.
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Caradiodoc
Feb 5, 2013.
Oh so I am doing the ignition-off draw test with a multimeter. I disconnected the negative battery cable and hooked it in series with the system. I have it set on 200ma setting and I am getting a reading of 23.4 on the meter. So I believe that means there is 23.4 milla amps on the system? Its been on there for an hour and has not moved much. From what I have read this is normal draw for the system. Is it worth testing the fuses to see if anything is off or is it time to trouble shoot something else. And if so where do I start? Thank you

Tiny
Leggatron
Feb 7, 2013.
Unless specified otherwise by the manufacturer, 35 milliamps is the maximum allowable current to maintain the computer memories. At that rate Chrysler says a good battery will start the engine after sitting for three weeks. You are within that range.

Somehow you got lucky to get that reading. You inserted the ammeter correctly but since the mid '90s there are computers that take up to 20 minutes to go to "sleep" mode. For that 20 minutes there can be about a 3 amp draw and that will blow fuses in most digital meters. You have to start out on a higher scale and that means moving the positive meter lead to a different jack, or switching the knob. Later, when current drops down when the computers go to sleep, you have to switch to a lower scale to get more accuracy. Moving the lead or just turning the switch creates a momentary open circuit and that wakes up the computers. Then you blow fuses and / or have to wait 20 minutes again.

What you have to do to avoid waking up the computers is never allow an open circuit to exist. Insert the ammeter with it turned to a high-enough scale so it won't blow its fuse. When you want to switch to a lower scale, connect a jumper wire across the meter first, from the negative battery post to the negative battery cable, switch to the desired scale, THEN remove the jumper wire and read the meter.

With your normal current reading, there are only four things I can think of to look for. First of all, are any of those batteries fairly new or are they all near the end of their life expectancy? Failed batteries develop a shorted cell when enough lead flakes off the plates and builds up in the bottom of the case. Right before that happens, there is so much lead flaked off that there isn't much left to hold a charge and there may not be enough current to crank the engine.

Second, check if there is a greasy film on top of the batteries. That is due to over-charging or due to the battery is about to fail. When a lot of lead has flaked off, what little remains is trying to absorb the full charge. It overheats and the acid boils causing bubbles to bounce against the underside of the top of the case. Some acid gets pushed out between the posts and case where it condenses and forms corrosion on the cable clamps, and some goes out the vent caps and condenses on top of the case. That greasy film is conductive and will discharge the battery.

The third thing is there could be something turning on overnight. That has become a much more common problem as we add more and more computers to do things computers were never needed for before. Sometimes you can catch that by leaving the meter connected overnight on the 200 ma scale. It can be turned off. Current will still go through it. If its internal fuse is blown the next morning, something turned on that drew more than 200 ma.

The fourth thing to consider is the battery is never being fully recharged. Measure the battery voltage while the engine is running. It must be between 13.75 and 14.75 volts. If it is low, it may be high enough to not turn on the "Battery" warning light but it may not charge enough to crank the engine. That is not really suspect here since you're having the same problem right away with different batteries.

Caradiodoc
Feb 7, 2013.

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