1997 Ford F-150 Repair Question
Windshield leaks are indeed very common and the water does drip onto the GEM module. That module controls a lot of stuff that used to work fine without a computer. It may help to search under the dash while a helper runs water around the windshield from a garden hose.
Since this is so common, some people believe it's not due to the windshield sealant, but rather due to a gap in one of the pinch welds. The solution may be to relocate the module or to cover it with a plastic bag. Replacing it won't be a permanent fix if water continues to get into it.
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