Vehicle Speed Sensor (VSS) Location?

[3/4 Ton Blazer]

I have an '89 Chevy K5 Blazer, and I got a code saying that I have no VSS signal (I also verified this by watching the datastream while the vehilce was jacked up and in gear). My vehicle is an '89, so it has a speedo cable (I think they went electronic in '90). My cruise control also does not work, assuming due to this sensor. After looking on Alldata, it claims that the VSS is located on the transfer case, but I have been told that it is mounted to the gauge cluster before. So I looked on Partsamerica.com, and they offer both sensors for my car! Where is the VSS that feeds the signal to the ECU?

 

[BulldogK5]

I always though it was on the transfer case. Not sure on the '89 though. I thought those were mech. speedos.

The cruise probably doesn't work due to a poor design for the controls. The button on the end wears just enough or gets just enough dirt in it to prevent any contact. My '88 had the dirt/dust issue. I could push in the button and spin it some to get it to make contact to set the thing.

 

[dyeager535]

'89 VSS (buffer) is bolted to the back of the speedometer.

They really shouldn't fail, but I suppose anything is possible!

I'm not sure how to test the output signal from the buffer, it's simply 12V, ground, and the output for the ECM, and cruise output if so equipped.

 

[3/4 Ton Blazer]

I always though it was on the transfer case. Not sure on the '89 though. I thought those were mech. speedos.

The cruise probably doesn't work due to a poor design for the controls. The button on the end wears just enough or gets just enough dirt in it to prevent any contact. My '88 had the dirt/dust issue. I could push in the button and spin it some to get it to make contact to set the thing.

The Cruise needs the VSS signal to operate, and the VSS is dead on my vehicle per the ECU code. It looke like I need to dig into my Speedo and see if my VSS is OK.

 

[ryoken]

it may be easier to test the vss output over at the plug where it goes into the ecm with a probe by just dropping the glovebox...