Truck Repair: 02 F150 Electrical problem, heater fan, climate control


Question
After a rain or snow, electrical system does strange things. When I turn the key to start, the heater fan comes on and stays on, engine turns over, but won't start and when I remove the key, heater fan keeps running.  Only way I've found to stop the fan is to pull the #105 fuse (Climate Control Front Blower) under the hood.  

Once things dry out, engine will usually start.

Where should I begin checking?

Answer
Hi Carl,
I would think some water is running down somewhere and causing a relay to close.
You could just try spraying water on the hood, down in the cowl under the windshield, etc on a dry day, and see if you can cause it, and then look to see where the water traveled.
Could be going in behind the hood, and running across the connector through the firewall.

Van