heater runs without truck started?
 

havent driven my truck in a week or so, but decided to take it to work the other day, problem my battery was dead, fairly new battery, jumped it and drove it to work, when I got there and shut it off, heard something running, it was my heater, the truck was shut off, any ideas?

Can you complete your profile or post some information on your truck ( My, engine, cab config, trim level ).

Heater could be wired to always hot instead of hot when running. Sorry not sure what the technical terminology is.

97 F150, 4.2 , any help would be appreciated

2 things.

#1 the battery was dead, and you used the alternator to charge it ??

#2 have you had a lot of rain or melting snow as of late ?

yes it has been warming up here lately, why would melting snow make it do that?

It sound similar to the symptoms that happen when there is a windshield leak, and the GEM is getting wet.

Pull the driver's side kick panel and check for signs of water where the kick panel meets the carpet, and under the carpet.

If the GEM is getting wet, you will need to

1. Get the leak fixed
2. dry out the truck, and see if the symptoms go away.

Heater is not working
 

If you've ever driven cross-country and stopped overnight at a truck stop or rest area, you know what I mean. All the trucks have their engines running through the entire night. I've noticed this during the summer and winter, doesn't matter which.

ok thanks will see what I can see, will check back in with any updates