Speedo & ABS Light

Lianimal · #1 09-11-2007, 08:38 AM

With the help of prior posts, I thought I had solved a problem my D's having with the ABS light on and the speedometer not working.
Went ahead and changed the rear wheel speed sensor. Thought it was cleared up, but when I drove the D yesterday - the same thing happened but only for a short time - took about 5 minutes and then the ABS light went off and the speedometer started working.

Anyone know if I have to change the 2 front speed sensors as well?

master tech · #2 09-11-2007, 10:07 AM

The speedo works off the output sensor thats on the tail housing of the transmission. ABS lite maybe other problems, fuse, module or tone wheel on rear diff.

Lianimal · #3 09-11-2007, 10:14 AM

Master, Would any of the issues you mentioned come up on the computer? My mechanic hasn't been able to get a reading for anything.

Kensai · #4 09-11-2007, 11:55 AM

There are two sensors, a sensor located on the tail end of the transmission. And another sensor that is located at the axle. I think the sensor located on the tranny is to monitor the speed for th speedometer and the sensor that is on the rear axle is to monitor the ABS system. I always make a habit when one goes out, just change both of them. These two sensors are very common issues on 1st gen durangos.

Otherwise, it may be possible your replacement sensor may be on the blitz also.

Lianimal · #5 09-11-2007, 01:54 PM

Thanks for the input Kensai. Any idea what the sensor on the transmission is called? Is it the vehicle speed sensor?

I know I can easily find out by going to the dealer, but as with most dealers in the NYC area - the Dodge guys by me are terrible.

Sunshine808 · #6 09-11-2007, 08:57 PM

I have no clue as to what their actual (sometime I make up my own)names are but I had to change both of mine. My speedometer never went out tho. The back wheel sensor went out first. Then about 9 months later the front speed sensor also went out.

Is your truck lifted or running larger tires? I have been told that it's a common issue with them going out every so often if you have those kinds of mods.

Kensai · #7 09-11-2007, 10:10 PM

The names of the sensors are Output sensor and speed sensor. I still get confused which is which? haha. I would assume speed sensor is the one on the tranny and output sensor is the one over the rear axle. My speed sensor starting to go haywire so I had that changed out and decided also to change out the sensor over the axle. They both kinda work together so best to eliminate them both if you have an issue.

Kensai · #8 09-11-2007, 10:11 PM

I do not think the size of the tires affects the sensors. But the size of the tires do affect the accuracy of your speedometer. Usually you can buy a programmer and it can recalibrate the speedo.

master tech · #9 09-11-2007, 11:38 PM

The sensor on the transmission is called an output turbine speed sensor. And yes a tech with a scanner should be able to read the rpm reading from any sensors. The tone wheel on the other hand, you would need to remove the inspection cover on the rear diff. But the best way is to pull out the sensor and look at it, if you see metal chips on the end of the sensor, you may need to go into the rear diff.

Lianimal · #10 09-13-2007, 11:49 AM

Thanks for the help guys. The sensor I already changed on top of the rear diff was the rear wheel speed sensor. I'm gonna go ahead and order the output sensor now and start there. I'll let you know what happens.

You guys rock!