Seller said windows were left down in a rainstorm. He managed to get them back up somehow (without removing door panels), but both won’t work at all now. Fuses are O.K. Operating driver-side button, can hear a mechanical click. Hooray for A/C!
Likely corroded switches or maybe worn out window regulators
Remove door panels and test wiring.
Leaving the windows down in the rain should not affect their operation. Some water gets inside the door every time it rains, regardless of the window position. That’s why there are drain holes in the bottom of the doors.
All you can do now is remove the inner door panel and start investigating.
Anytime water falls on the door mounted switches, it slides down to the switch contacts and starts corrosion.
This design (although convenient) has resulted in years of bad switches.
This, to me, seems to be a recurring problem with FoMoCo products. Have had the same problem on an 84 Merc Grand Marquis Colony Park S/W and on a 2000 Town Car. The TC master control acts as if the contacts are corroded and as if there may be a short. Is there any way to clean and/or replace the contacts without replacing the whole master controls?
Did you buy the van yet? If not, have the price lowered by about $1200 for a Ford dealer to replace the regulator/motor sets and the switches. Unless it’s wiring. Then you need to factor that in. Get the problem checked by a mechanic to see what it is and then adjust the price down using Ford parts and labor.
If you did buy it, you need to start with the cheap stuff. Inspect all the contacts in the connectors for oxidation. If you find some, let us know and maybe we can help you clean the connectors. You can also check the connectors for power with a volt-ohm meter. If you have power on the wiring harness side, check for continuity on the switch side. If there is no oxidation and no power on the switch side, the switch needs to be replaced. If there is no power or oxidation on the harness side, you have a wiring problem. Don’t assume that the problem is related to what the owner told you. He may be right, but the problem may be coincidental and not related to water damage.