Re: Early 99 f250 6 speed no speedo and abs light on.
The psom is a module that is part of the instrument cluster. If it is bad the whole cluster has to be replaced. The gem module is an electronic control module located directly behind the fuse panel under the dash. It is quite common for the windshield to leak directly onto them which shorts them out. You can pull the module and look for signs of water or corrosion.
97 F-350 XLT CC DRW 4X4 PSD, 285/75-16 Custom bumpers, Gauges-boost/egt/trans, Swamps IDM, 3.5"dp- 4" exh., 3" Body lift, ES bushings/mounts, Built trans, billet conv, B&M pan, Hayden cooler, Adrenaline, stage 2's, IC, H2E, E-fuel
ARP's, 910's, Smith Bros. to come