I KNOW THIS HAS PROB BEEN ADDRESSED B/4,But haven't seen it.
2000 Dakota Sport 4x4, just bought it. abs & brake light comes on & speedometer quits working intermittenley, replaced sensor on r/e cured prob for 2 days now back to same prob??? Any ideas??? Thanks, Bill sorry forgot 4.7 V8 A/T 4x4 Quad cab

 

anybody??

 

Ok, been reading past 1 1/2 hrs thru old posts, still at a loss on prob. 2000 Quad cab 4x4, 4.7, a/t. bought truck couple weeks ago. abs & brake light comes on & off erractically, speedo quits working. everything may go back to normal in a few minutes or not until I shut truck off. then lights may or may not come on>> have replaced rear speed sensor, saw a post where I should change r/e grease? HELP I don't have much hair to pull out.....

 

Welcome to the forum. Give us time to respond.

Check for codes.

With key off, turn it to run (not start), then off, run, off, and leave it in run. You should pull up codes in the odometer window.

 

Hi Dan, thanks, there are no codes. changed r/e dope today, not much of anything in there except grease!! guess we'll see if that does any good.

 

I now have a P1687 code that shows up???

 

P1687, no MIC (mechanical instrument cluster) bus message.

It could be anything on the bus. The best way to solve this would be to use a DRB (dealer) tool that can communicate with all the modules on the truck. It should be able to diagnose the speedometer problem too.

Without that, about all you can do is check all the wiring carefully and then start swapping out modules - which gets expensive fast.

Wish I had more for you.

 

Speed sensor in the tail shaft of the transmission or rear diff can cause dead speedometer and abs light, been through that problem on both. DRB doesnt detect what one so dealer replaces both at the same time( i got lucky and did one, fixed the problem, then the other went out and replaced it later. Just a warning, dont do the trans one right after driving. you loose about a half quart of trans fluid and that stuff stays hot for a long time.