Power window might be blowing fuse?

[tcbusch]

I have a 2003 Silverado with a Duramax. Its a LT with heated seats and power windows. A couple of weeks, or months, ago I blew a 50 amp fuse. Its one of the square fuses in the fuse box located under the hood. The fuse is labeled MBEC1 and the description is Mid Bussed Electrical Center Power Feed, front seats, right doors. Both passenger side windows and the heated seats stopped working. The fuse did not flash blow or burn the surrounding plastic so I can assume its an overload not a short. I replaced the fuse and it blew a month or so later. I replaced it again and it blew a day or so later. I was trying to think of what could have blown the fuses and what was common about all 3 fuse blows. I remember the second time the fuse blew the back passenger window was down. The third time the fuse blew the front passenger window was open.

My question is what controls the window circuits. Is there a component that monitors the motor current that stops the window motor from running after the window bottoms out? I was thinking that maybe the widow motors are bottoming out without stopping causing the over current and blowing the fuse.

Any thoughts?

[tcbusch]

Well, after posting this question I thought I would Google MBEC. Sure enough I got a hit on the diesel place site. Another common denominator was I had the parking brake applied. The first time the fuse was blown I was launching my boat and placed the parking brake on. The next time I was at the in-laws and put my parking brake on because of their steep driveway. The last time it blew I was launching my boat again. According to the diesel place post it could be.

<LI type=1>"MBEC 1" Maxi Fuse 50 Amp (SI Document ID # 1242532). If no shorts are located on circuit 642, inspect circuits 1340 after the "Rt Door" circuit breaker 25 amp and circuit 1440 after the "Seat" circuit breaker 30 Amp (SI Document ID # 1242687).

• Inspect circuit 1340 shorted to ground near the right I/P support bracket.
• Inspect circuit 1340 or 1440 shorted to ground on the support bracket for the I/P relay block.
• Inspect circuit 1440 shorted to ground under or in either front seat.
• Inspect circuit 1440 shorted to ground near the parking brake pedal assembly. The short may only occur if the parking brake pedal is depressed.
Here is a link to the post to give credit where credit was due.

http://dieselplace.com/forum/showthread.php?t=97150

I will check the wiring by the parking brake tomorrow.

[silverado122775]

Thank you for the infomation.. I am sure this will come to use for someone.
Please be sure to post your results.

Thanks