I need to know why the battery always seems to die when the car sits for more than a couple days without being started. Is it the cold, a short? I'm clueless right now and would appreciate some feed back.I just put a new battery in truck 3 wks ago and the truck sounded great started right up. I just went to start up the truck today 3 wks later and nothing....PLEASE HELP!!!!! Thank You
I believe that it has something to do with a "high" draw computer. Plus the fact that it has been three weeks sure isn't helping any! Your computer is always active, thus constantly drawing power from your battery. I think that Ford has the high draw computers. I work for the airlines and have seen it all too often, the pilots go off for a week or so and come back only to have to have their cars jumped because of dead batteries. If I can think back enough I would be willing to bet that alot of those cars and trucks were Ford products. Aside from that you probably have a digital clock as well. It all adds up, especially over a few days time. I would suggest that if you don't drive the vehicle often enough to maintain the battery charge I would at the very least start and run it for a bit every two days. Or, you can purchase a trickle charger that will maintain the battery at optimum levels. Make sure the charger that you purchase is NOT a manual charger as this you would have to turn it off to avoid overcharging. I would say just buy the one that says its an automatice charger.
Searcher1
When we go off for extended vacatruions (often over 3 weeks), we never have to jump our 92 Sport, so I doubt this is the problem. There is a lot to be said for actually troubleshooting an electrical problem. Determining the actual draw will work wonders to find if an excessive draw is the problem,and will help immeasurably in finding where that draw might be.
Not true, you should be able to let that thing set for six months and start it. How many car dealers do you see with all the new car hoods open on monday for a jump start? Most likely it is the alternator that is bad, a leaking diode will drain the battery in a few days. Pull the battery cable off and check the current draw, should be less than 20 MA. also are you sure that all the lights are off? All new cars have a computer draw of 10 to 20 MA. Add the clock and keyless entry and it could go to 30 MA.
R> I believe that it has something to do with a "high" draw computer. Plus the
My neighbor asked for my help with a similar problem. His new van ran its battery down when left for a couple of weeks. He took it back and they replaced the battery under warranty.
This new battery also dies when left just the same as the old one.
I took off a battery lead and put a current meter in the circuit. The current was in the 100mA (or one tenth of an amp) range. This would take about 3 to 4 weeks to drain a 50 to 75 amp/hour battery. We removed other power drains from the circuit by pulling fuses, so we killed the clock, radio etc. We concluded it was the computer and I left him armed with too much bad information to go back to the dealership.
They tested the battery and concluded the second battery was also bad! How likely is that?
When asked about the computer they pointed out that when initially powered up it will draw full current but after a few hours it goes into an idle mode and only draws micro-amps. So the poster who suggested 20 to 30 milli amps is correct..... this would take over 10 weeks to flatten a 50 amp/hour battery.
I suggest that you charge the battery and drive to a Pep Boys or Batteries USA or where ever they have a free curbside battery test. They will put a load on it and see how much the Voltage drops. This is about the best way to test it.
David Raleigh
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