I got up this morning and my battery was dead. With my ignition off, my blower fan wont turn off and my interior lights stays on. I sure hope there is someone here that can help me, I'm stuck , it's my only vehicle and can't get into the shop untill thursday, thank for any help!!

 

I forgot it's a 99 f-250 superduty deisel

 

Are those the only circuits affected, anything else staying on or any intermittent?

The blower function and interior lighting don't really share any power distribution other than the Junction Box Fuse/Relay panel, or at least none that wouldn't cause other components to be ON for the most part.. The windshields can often leak (more so if a replacement) and the water runs down the harness on the drivers side cowl area and 'straight into' the GEM module and fuse panel.. The GEM piggy backs the fuse panel.. Can make for some weird 'conditions' from the moisture and/or corrosion if the circuits are bridged, open or shorted.. I'd look there first given their history, more so if you've noticed any small interior leaks.. Look up from the heel plate area on the drivers floor board.. Look for the harness as it comes down from the upper dash/cowl.. Look to see if you see any evidence of 'water tracking' making its way down to the GEM module.. If water enters the GEM and fuse panel you might see some green corrosion points as well..

Any other accessories on?

 

I thought i had it figured out, I pulled the relay/fuse out and switched it with another and it went off, so I thought it was the relay in the fuse box. But then when I started the engine again it did the same thing. I don't see any corrosion,or any apparent wet or areas that have been wet. Yea the interior light shouln't be connected but???? thanks so much for the reply, i really appreciate it- Steve

 

I agree with hayapower.

 

Has it rained in the past few days?If so it could be the GEM module.controls the body electrical.Check for a windsheild leak. its easy to change but needs to be programed by dealer.Dealer fix about 600.00 not including the windsheild.

 

I just want to thank every one for there replies, I was just good to know you guys are there. I was a little bummed. It does appear to be the gem mod. I have an appointment to have it diagnosed. This morning I got got up and put the relay back in,that I had pulled to stop the blower fan, and everything is working fine. Thanks for your prayers....lol. Well I talk to the parts guy and they want 300 for the mod + 1 1/2 hr install. He said it's not that hard to put in, and that you couldn't hardly mess it up. He didn't say anything about programming it though. Well once again thanks, I'm really glad I stumbled into this place, you guys are GREAT!!!!- Steve