Speedo Issue (help)

[sirdude]

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I have a 1996 Ranger, 4.0l, Auto, 2WD. Recently the odometer stopped working so I found the gear online and replaced it. Now the odometer works great, but the speedometer starts about 40 and goes up from there. It's not smooth ...very jerky and never goes down below 40. Additionally my brake warning light stopped working. At first I thought maybe I had dislodged a connector somewhere so that it didnt turn on when I depressed the emergencey brakw, but then I realized that it was nmot coming on when the key was first turned on either as part pf the bulb test. So I figured all the jostling around had broken the filliment on that bulb. So I pulled the whole thing apart again. I found that when I put the cap back on the speedo needle, I had pushed it a tad too far and it was barely making contace with the face plate of the speedo. So I fixed that. Although I could "see" nothing wrong with the bulb, I replaced it with a new one anyway and put the whole mess back together. So, nooowwwwww.......the odeometer still works great and as soon as I turned the key to on the speedo jumped ot 28 and that is as low as it'll go. When I accelerate, the speedo appears to register correctly from that point. Also...the damn thing now regesters when I go backwards!?!?!?! To add insult to injury, the brake warning light still doesn't work during the bulb check when turning the key to on, but it DOES work when the emg. Brake is depressed and if tthe the fluid level were low (I assume). Help....please??

Chris

 

[RonD]

Have a read here:
http://www.therangerstation.com/tech_library/speedometer.htm

The '96 uses a VSS(vehicle speed sensor) on the trans so that could be the problem, you can test it.

The odometer gear was a know issue, and is probably not related to current issues except in the wiring the was disconnected and reconnected during gear repair.
The Brake light issue would lean me towards a disconnected ground which could effect speedo as well.
Generally most newer electronic control systems supply power to everything all the time, then use the ground as the control, so the Brake light has power when key is on, but no ground so bulb is off, control system grounds all the bulbs as a test on startup, then ungrounds after startup.
Setting the e-brake grounds the bulb, this is a mechanical ground so would tend to work all the time.
The fact it doesn't come on with key on would lead me to believe the control ground is not connected.

So maybe you missed a connection when reassembling?
Or have a connector not pushed together all the way?

 

[sirdude]

Thank you for taking the time and effort to respond, it is appreciated. I doubt its the VSS as I had no problems until I took it out to fix the odometer. I suppose that COULD be the problem, but it would be quite a coinsidence. As far as a disconnected ground, I'll buy that....makes sense. IT would be hard not to reconnect properly as the connectors (three of them) "lock" into place. I wonder if one of the ribbons on the circuit board got damaged when I reinstalled the cluster...have to check that out. I had already read that artlical, but thank you for sending it. Again...thank you for your response...when out gets a little warmer, I'll pull it again.