I'm having some difficulty on my 90 B250. The speedo stopped working so I took the dash apart and got it to work, the plug worked itself loose. Then the shift indicator didn't work, so I fixed that, then the speedo stopped working, back and forth like this. And the speedo does not come out like it is supposed to. Is there some trick I'm missing here?

 

Is the shift indicator mechanism rubbing the connector to the speedo?

 

Well I fixed the indicator. I checked everything for the speedo and nothing seems to be out of whack. The speedo keeps cutting in and out, could the gears for the speedo be stripped in the dash? or is it more likely the gears in the tranny are stripped? I took the dash apart to remove the speedo to inspect it, and double checked with my shop manuals to make sure I got all the bolts and my speedo will not come out, don't want to pry too hard on plastic.

 

No, the shifter is not hitting the speedo. My speedo is starting to work more off than on and the overdrive is starting not to function correctly either. Could this be a speed sensor issue, and is that part of the cruise control unit? If the gears were getting stripped would it still be intermitant? Is there something I'm missing?

 

When I was in Australia, I owned a '73 Holden. Over a period of 1000 kms the speedo would sometimes cut out, then re-engage. It slowly became more frequent, until it finally stopped all together. When I pulled out the speedo cable I found it broken. Obviously after it broke, the 2 broken ends would meet up and engage and the speedo worked for a while longer, until the broken ends could no longer mate anymore.

So Either you have a stripped cog at the tranny, in the speedo, or a broken cable.

I don't know if your VSS is the same as on my '89 but if the bolts holding the speedo cable to the VSS were loose, I could envision the cable not always engaging the spinning magnet in the VSS.

I know another poster's '88 has his speedo cable going into his CC.
My '89 does not.

If the VSS is not being spun by the speedo cable on my year, the OD will not work.

 

Ok so apparently there are no cables anywhere for the speedo. So I traced all the wires and checked all the plugs and they all look like brand new. I took pictures of the speed sensor and it appears to be fine. It spins freely and when you push down in the cable thing it springs back, I think it's supposed to do that. So it seems to be something with the speedo itself, and I can not remove it, so it looks like I might have to replace the whole.gauge cluster with the white plastic thing and all. Everything behind the dash appears to be attached properly and nothing is broke, there are no loose wires and nothing is unplugged.

 

Okay, I didn't realise they went all electronic in '90.

That VSS just connects right to the tranny right?

That VSS looks very similar to mine, except mine has an output shaft for the cable.
If your works on the same principal as mine, there is a spinning magnet inside. This magnet opens and closes contacts within. The speed these contacts open and close send a signal to the ECM, which I assume, on yours, makes the speedo work.

If you have a DVM, set it on OHMS, connect the leads to the electrical pins, and manually spin the rotor. the ohms should read 1,0,1,0,1 ect as you spin it. About 12 times per revolution.

Mine will get sticky, and work sometimes, then not others. I flick it with a finger and it works.

 

On some dash clusters (especially high mileage vehicles) the electrical contact pins that are inserted into the circuit board get loose. Use a 25W soldering iron and run a bead of solder around the base of each pin to restore the connection to each foil tracer on the board.

This cures all kinds of cluster troubles from flickering gauge lights to intermittent gauge problems.

 

Here's a pic of my '93 B150's soldered PCB cluster pins from the archives:

 

My van has about 130,000 miles. I can't get the cluster out, but if I can figure it out I will definitly check those pins, thanks. I checked my speed sensor and it appears to be working correctly.