So I have a problem with my speedometer, It just stopped working one day with no warnings. I changed the sensor at the rear axle and still nothing, I checked the fuse and sure enough it was blown so I figured new fuse and I'm good to go. Wrong, new fuse blew instantly so I started my search for the problem and can't seem to find any issues??? I read through the forums and a few suggestions say to take out the screws at the dome light (sometimes they short out and cause the same fuse to blow) tried that still blowing fuses, removed the outside cab light to see if that may be the cause, still blowing fuses. traced out wires from rear axle to front wiring harness and dont see any obvious issues.
I'm wondering if the speedometer unit itself is shorted? also does anybody know if the miles drived while it's down are being recorded? dont really care if they are just curious.
Any help or ideas are appriciated.

 

If the spedo is out then the odometer isn't working either cause its registering as the vehicle not moving. You will ave to inspect the wires up near the speedometer/ odometer module (PSOM) which is way back behind the dash behind the gauge panel.

Is it fuse 18 that keeps blowing?

 

Figured this out just in case anyone else runs into issues, my problem was with the drivers side door pin switch, the wires were chaffed and caused a short just behind the kick panel, cut back the short and rewired, no more issues. I wouldnt figure that the speedometer is tied into this circuit but on my truck it sure as hell was. spedo is now working fine.