Hi guys/girls..i'm a newbie here however I've read tons of posts on this subject.
My ABS/Brake light is on...ok...so,I've changed my rear speed sensor,front abs sensor,check for good continuity from the abs module harness to the rear sensor,both wires are showing 0 resistance. I've check the resistance between the sensor and from the dealer's spec its showing good. I've check the tone ring in the front and rear and there in perfect shape. I check for metel shavings on the sensor but its clean as could be. I'm at my wits end....can someone help?

 

Hi guy's/gals..i forgot to mention....i did find that the stock rear speed sensor connector was rotted beyond repair. Being a dodge truck fan i knew that i could use a 1998 ram speed sensor because there the same size,length and that i could order a new sensor and connector for 15$ so i spliced and used a sensor off a 1998 ram. Are the sensors the same??

 

What is your year and model? and is it 4x4 or 2wd?

 

It's A 2008 , 4x 4 , auto , 5.7 hemi, Rwal ....funny thing, I found a short going to the rear sensor so i replaced the wire. Now I have no lights in the dash (abs & brake)....and no speedo. Any help ?

 

The only sensor that the 2008 shares with the 1998 is the tone sensor on the read differential for the ABS system, but there is a different connector if you have traction control or not, so that might be the issue right there.

Also there is a big difference between the 4x4 and RWD sensors as the RWD mounts on the front wheels and has another one on the rear differential, whereas the 4x4 just has one on the rear differential.

Also a reading of 0 Ohms across a sensor would indicate that there is a problem, as every sensor has some kind of internal resistance.

If you are measuring a wire without a sensor to try and find a short if you are using a good multimeter you should get an "OL" (aka Overload) reading that will tell you that the wire is good, any other reading means the circuit is incomplete (telling you that there is a break in the wire somewhere)

No Speedo means that you either have a bad speed sensor, bad connection to the speed sensor, or you didn't install it correctly.

Buy a NEW sensor from www.rockauto.com or from the Dealership and put it in.

I am just speculating what the problem is most likely, b/c I can't tell for sure without looking at the truck myself.

 

Ok so I found a short going to the rear abs sensor,and after replacing the wire the lights all went out and seemed all is good. I did measure the resistance across the #1 & 8 terminals from the abs connector and was reading 1850 ohms with the sensor plugged in. I also did a small test. I disconnected the front abs sensor and went for a drive ,no lights and no speedo. Then I disconnected the rear sensor and reconnected the front sensor. Then the lights returned with the speedo. Any ideas ??

 

That is the problem.... you need both sensors hooked up and working to get the speedo and ABS to work properly.