Questions and Answers
Three Days, Dead
Q. Dear Auto Guide, I have a 1991 Astro van with 135,000 miles on it. Cruise control and four speed automatic transmission. After three days of not using the van, it won't start. I have to charge the battery for like five minutes so it can start. However if I use it the next day it will. Only when the van sits there for three days it won't start.
I thought it was the terminals but replacing them didn't help, and I'm sure it's not the battery because I've used a new one and the problem still occurs. Any info will be greatly helpful.
Thanks,
BillA. It sure sounds like there is a key-off current drain that takes two or three days to kill the battery. In general the key-off current should be less than 300 milliamperes. This will account for the clock, radio memory and PCM use. If it is any higher than that, the draw will kill the battery.
The way to check it is to remove the positive battery terminal and connect an ammeter from the battery post to the terminal. This will give you an accurate current draw reading. If the draw is high than 300 milliamperes, pull fuses from the fuse box until you find the circuit that is causing the draw. Once you know which circuit is causing the drain, then you can track down the draw and repair it.
Additional Information provided courtesy of ALLDATA
