Electrical problem

[Cummins12V98]

Hi all,



A friend has a 93 1 ton dually. A while back he replaced his speed sensor and all was good. Now after a year of so his speedo does not work or odometer and it won't go into OD. He just replaced the speed sensor with a part from auto zone and still same problems.



Thanks!

 

[Cummins12V98]

Anyone??????

 

[DVolk]

id try electronics cleaner is the floor boards getting wet if its like mine it is and water is probally shorting things out , id also check the fuses also that vss might be bad or striped off

 

[Cummins12V98]

id try electronics cleaner is the floor boards getting wet if its like mine it is and water is probally shorting things out , id also check the fuses also that vss might be bad or striped off

Thanks,



His truck is in a dry climate. Sorry what is vss?

 

[JMDancoe]

I believe Donovan is refering to the unit that goes on the back of the transmission or (on 4WD trucks) the rear of the transfer case, where the old speedo cable used to go in. You need to remove the unit and see if the little square drive or the hole into which it goes in the adapter are stripped. If either or both are stripped, the speedo, odometer and OD units are not getting any message showing that the truck is moving forward.

Also, if a 4WD, the nut that holds the U-joint yoke on the output shaft is loose, it will not read either. Hope this helps.

 

[Cummins12V98]

I should have mentioned it is a 2 wd

 

[DVolk]

same diffrence if that is striped out or the wire is broke you get the same issue , one freebee check you can try is un plug the cruise controll and see what that does , some times they play hell if the switch goes bad

 

[HHhuntitall]

Try to figure out if the mechanical part in the tailhousing is turning. It could have stripped on the output shaft, too. I'd put is on a set of stands and turn it to see if it's all turning. If that all checks out, and the points in the above posts, then you may have a failed PCM... .

 

[Cummins12V98]

Thanks for the help guys! Will try your suggestions.