Archived no spedo/Tach stuck in drive

[GKastner]

Please help

1st time posting and new to this

My truck is stuck in drive, no speedo/ tach. Local shop said alternator is gone and took plc with it. replaced both and took to local dealership to have plc flashed. No communication between truck plc and diagnostic equiptment at the dealership.

 

[AKAMAC]

GKastner, welcome to the site.



Did they replace the PCM or ECM? Tach and Speedometer are read by two different sensors. If you have the old PCM try putting it back in and giving the dealer another shot at it. Also give the data for your truck. Year ,2500 or 3500, ect. Hope you get her going. Mike

 

[GKastner]

Thanks for the reply,I'm going back down to the dealership today to ask but I think the original pcm has already been sent back for the core charge. I've been down a week and need my truck back for work. Greg

 

[DMcClenaghan]

A similar problem happened to me recently. I thought it was the PCM, but found a fuse in the underhood box had fatigued in half. . no electrical flash, no melting. Check the 20A one marked "Fuel Pump" . I ASSumed it did nothing in the diesel model, but replacing it fixed the problem.