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Battery shorts out when less than half a tank? Weird, right?

My 2000 Ford Windstar’s battery seems to short out randomly when I have less than half a tank of gas. It starts out with the guages going crazy…jumping from one extreme to the next (even the spedometer!). Sometimes the lights nand radio begin to flicker. The battery light comes on. Many warning lights begin to turn on…the abs light, the traction light. In the info window, the statement comes up “check charging system”. Begins to feel like I am running out of gas. In order for me to keep the battery from dying, I have to pull over immediately and wait for a few minutes with the van in park. After a few minutes, everything will go back to normal. If I pull over too late, the car battery will die and I will need a jump. As soon as I get some gas in there, everything is just fine. What is going on!!!

When you get the gas in…will it run fine even without getting it jumped??

Definitely sounds like something is shorting out. Tracing it could be a problem. Is it in the tank…or the gauge???

It sounds like the PRNDL (prindle) switch or as Ford calls it the Transmission Range Switch is malfunctioning. A common problem.

This switch sends it’s signal to the Engine Management Computer and to the Body Control Module. If this switch fails it can cause all sorts of electrical problems. Most times when this switch starts to fail people will complain that the radio will cut out and come back on and the speedometer acts erratic. Then as time goes on other systems start acting erratic. Dash lights flash off and on, wipers act erratic, power windows act erratic, etc…

Tester

The same kind of thing happened my sister-in-laws Windstar. The trouble was due to a bad alternator. From things that you stated I wouldn’t be surprised if the same thing was going on with your van. If that isn’t the problem then I would look for a problem within the main power bus or the ignition switch. @Tester advice is good also.