speedometer is not working why?

check your speed sensor in the transmission and se if the wires are broken/chafed and grounding out. check the light for the gear shift indicator. Also check the VSS and buffer here are the locations. Check out the diagrams (Below). Please let us know what happens.

i changed the backlight bulbs in the instrument cluster that were burned out , now the speedometer does not work, the other gauges work and the lights i put in do not work. it is not a cable speedometer, so i am at a loss. help please.

The first thing I would try is a VSS vehicle speed sensor I have also seen the buffer go out here are the locations. Check out the diagrams (Below). Please let us know what happens.

i moved the dash bulbs i replaced and changed sides, the side that was working now is out and the side that was out is now working , i think i may have damaged the printed circuit board or a fuse. so I got a used cluster still nothing. Then I replace the buffer all set thank you.

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My speedometer in my 94 Chevy 4x4 truck is going nuts. It says I'm doing 85 while stopped at a light, sometimes goes like a windshield wiper, and then sometimes works OK, but occasionally bounces a bit. Seems to work best when air temp is cool and worse when it's hot.

Since the transmission is tied to the speed sensor, it has had trouble choosing a gear when going uphill, often choosing the higher gear.

I replaced the speed sensor last weekend, but it's still acting up, and seems to be getting slowly worse. I had the transmission fluid replaced about 3 weeks ago (it was black!), and the trouble started about 10 days later. I don't know if it's related.

i had a 1994 chevy with the same problem. there is a control module behind the dash board. each one of these boxes is made for each truck. the speedometer won't work unless you have this box sent in to GM and have it rebuilt i guess. i never did cuz it was to much of a hassle. i just knew that when the tac was sitting at 2200 i knew i was going about 70. good enough for me. i hope this helped a little bit

I had my auto electrician look at it. He replaced the instrument console, but no dice. All the wires are good, so he says it's the buffer. I guess we'll find out what happens when he gets the new part in.

I was driving the truck at normal city speed about 40 mph, and on a slight incline when the transmission felt like it downshifted for a slight second. At that point, the speedometer stopped working and the truck only had 2nd gear. Reverse works fine as well. I limped home in 2nd, keeping it under what felt like 45 mph since I had no speedo. Looked at it today and found a couple things that are confusing. Transmission fluid looks and smells fine. Found a vacuum line coming from the top of the transmission hanging there severed, but have no idea where it should go to in the engine. Also looked in the Haynes manual which shows diagram for the TV cable, but I am not seeing it or any remnants of it. I have a 5.7 liter engine and I assume I have a 700R4 transmission. Need to know if the TV cable could have completely been "ripped" away, or if maybe it does not even have one. Also need to know about that vacuum line and what it does if anything. And of course need to get some clues about the speedometer. No cable so it must be electronic. Would rather not take it into a transmission shop if it is something minor.

Hi
Trans is 4L80-E controled shift by PCM most likely fault Vehicle Speed Sensor located on left side trans in tail shaft has wire connector. if it goes speedo and trans goes into fail safe mode.
Hope this helps
Thanks for donate

I change the sensor behind the glove box, also check the wires on the tail of the transmission looks fine. Any other suggestions? My transmission has been rebuilt and my old transmission it didn't work as well.

Okay. Two questions. Is this 4WD? Is this an automatic or manual transmission? The cluster gets the signal from the vehicle speed sensor buffer. So we need to make sure the VSS is operating before we go much further.

I have 2 wheel drive auto, what have me worried is my old transmission was doing the same thing. But I replace the transmission for a rebuilt. So could it be the plug?

Okay. So you changed the buffer already? If so, either the VSS is not sending a signal to the buffer or there is a connection issue as you are stating. Either way, the

Does the odometer work? It's possible the cluster is the issue but I would not go there until you prove out that the VSS is giving a signal and the buffer is sending it to the cluster.

I have a 2003 chevy silverado 1500 truck with a V6 4.3L engine with 134000 mileage on it. the speedometer does not work but the odometer and the hours useage meter work. I replaced the speed sensor but it still does not work. Is there a fuse for the speedometer and if so where is it located? Thanks

the speedometer has been running about 10-15 miles per fast. I have the same size tire and wheels that came on it and have replaced the speed sensor in the transmission, but it still reads faster than I'm going. The sensor cost me about $ 62.00 and didn't fix a thing. I read somewhere that there is a vss buffer on the left side of the dash, does anyone know where and what it looks like and how to check or replace it?

Thanks,

jerry Mills