I just acquired a 1992 4x4 S10 Blazer and the ABS indicator light on the dash is always on and digital speedometer does not work. I checked the Brake fuse in the fuse panel and it is not blown, so I'm assuming that I have a bad ABS speed sensor....is this the correct train of thought?

If so, is there one particular sensor that would trigger the indicator light to stay on AND the speedometer to not work or would I have to troubleshoot to find the bad sensor?

Also, not sure if this helps or is related, but the brakes are really spongy...I have to depress the pedal all the way to the floor to adequately stop the vehicle.

Thanks in advance for any tips you can give to help resolve this issue.

 

first off,the digital dashes are junk. they always start loosing gauges etc then it'll all go out. Ive had em. you can do a analog cluster conversion if you are good at reading a wire diagram.

check the "gau/ign" fuse. its a 20 amp. see if its blown.

 

The light and gauge issue may be caused by a bad VSS on the rear of the t/c.

The brakes may need to be bled, or possibly the rear brakes are out of adjustment...

 

The "gau/ign" fuse looks good.

Unfortunately, the cluster conversion is more than I'm comfortable taking on...no good at reading wire diagrams.

 

Thanks, I thought it could possibly be the VSS, as well, but was not exactly sure what I'm looking for.

How do I tell what the VSS is and if it's bad?

 

look at this for the conversion. Instrument Cluster Conversion


its actually vis versa (analog to digital) but just look at the wire colors and match em up.

whoever did it took some time to make it and i appreciate it! its what i used to convert mine to analog.

 

i do remember when my gauge fuse blew,my speedo and oil gauge stopped working,and then a min later my brake light came on. I do remember someone telling me the abs runs off the speedo too. not sure about that though. this might all be tied in on the speedo.

 

The ABS system uses the VSS as the speed reference for the rear axle, as does the speedometer.

The VSS is located on the rear output housing of the transfer case, on the drivers side. It has a 2-wire connector to it.

 

I found this by doing a google search for the issue:

ABS & Brake lights warning indicator steady on dash and speedometer not working for Dodge Ram?

The rear differential speed sensor is also the rear ABS sensor. Since the speedometer also needs to know the vehicle speed it seems like this the most likely source of the problem you are describing

I thought it could be the same for the Blazer, but I believe there are 4 ABS speed sensors on the 4x4...one on each wheel.

 

Thanks, I'll check that when I get home today.