Drained battery

2002 ford expedition, after sitting for a few days, something drains the battery. I have heard it was the rear wiper causing this, any opinion on this and a solution? Thanks all.

It could be the rear wiper, it could also be a bad battery, it could also be something completely different. The only way to find out is to diagnose it.

The best way to diagnose it is to do a parasitic draw test. Eric the car guy has an excellent video on YouTube detailing how to do one.

If the rear wiper is causing battery drain on your 2002 Ford Expedition, it's likely due to a faulty wiper motor, switch, or relay that leaves the system powered even when off. To confirm:

Remove the Rear Wiper Fuse – If the battery drain stops, the wiper system is the cause.
Test with a Multimeter – Measure current draw with the ignition off. If it’s high, pull fuses one by one to pinpoint the issue.
Repair or Replace Parts – If the wiper motor or switch is at fault, replace them to stop the drain.