instrument cluster problems

[01CumminsSport]

im working on a 94 12v and the tach doesnt work and its not charging, dont know if its the same problem, as in the ecm isnt seeing a tach signal so its not switching the alternator, any one have any info on this?

 

[tdshepard]

ESS (engine speed sensor) mounted just above balancer on front of engine. Make sure gap is .050, check plug connector, check wiring for wear. About $75 at Cummins dealer.......

 

[01CumminsSport]

one more thing, the customer remved the instrument pannel and when it went back in those 2 gauges didnt work but did before the pannel was removed