How many speed sensor on a 2001 378 with a eaton, fuller 13 speed

Does cruise control work?

 

You didn't answer the question on your other post.

I'm 1995 379 12.7 with Eaton 13 speed and Motive.

If your truck speedometer is working correctly - then the ECM should be receiving truck speed data.

What are the two lights on your Motive box doing?

There's one sensor on the bell housing at the bottom that screws all the way in then 1.5 turns backed off and jam-nutted, but I can't remember if that's tach or speed.

Call Motive - even though it's overseas tech support, they are pretty helpful and can see your unit, location - everything - if you are in the system. I had to call and have them help me when I got a new phone the other week.

Frustrating technology for those of us who were happy scribbling in a coloring book every day.

 

The one on the bottom of the flywheel housing is engine speed/rpm
I wouldn’t say for sure that because the speedo and odometer are working that the ecm is for sure getting a signal…some of the “early”computer engine trucks had a separate system so to speak for the ecm and the dash.

 

Yeah - you're right - I slowly remembered, I had to check/replace because of a tach issue that wound up being the gauge itself.

Does the speed sensor come from a sensor on the tail shaft? If his speedometer is working then ECM should see it too.

I've got a 'Scan Gauge' plugged into mine that shows all ECM information - CC setting, speed and RPM are all read - that would verify his available ECM parameters being read. It's handy for checking gauges on dash to actual digital readings - all my gauges are off on the dash by 5-10% from what the ECM reads.

 

Speedo sending unit has always been on the tail of trans with the eatons I've fiddled with.

 

It could be set up one of 2 ways. A single speed sensor on the tail shaft with 2 identical plugs. One for dash one for ECM.

The other possibility is both on tail shaft one at angle from a bottom corner and adjustable the other a push in from the top with a small weather pac 2 prong connector. Which is the one your hunting if it’s set up that way

 

Read @wore out post again and chase that 2nd wire to the ECM ?