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420A 2GNT speedo not working.

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eclipse0508

15+ Year Contributor
270
1
Nov 17, 2003
Plattsburgh, New_York
I have a 1995 eclipse GS and i just took my car out of storage for the winter. I started to drive and i noticed my spedo and my odometer are not working at all. I was wondering what the problem could be. Although they arent working my tach is working. Any help would be appreciated.
 
Check that the VSS is plugged in firmly. Pull the VSS and inspect the pinion.
 
Thanks for the reply, could you possibly point me in the direction of where the speed sensor is??? I've never had to deal with this situation before.

Thanks again...
 
It's on the back side of the tranny, facing straight up. If you feel around directly below your throttle body, you should be able to find it. It's held in with one 10mm screw.

The tachometer is controlled by your ECU based crank angle sensor signals; so that explains why the tacho works. The speedometer and odometer are controlled by the VSS, so I'd put my money on something being wrong with the sensor. If the sensor checks out, then it could be the connected from the gauge cluster to the wiring, or the gauge itself.

My speedometer never worked since I got the car. I replaced the sensor and cleaned all connections. Finally, it turned out to be the gauge itself. Luckily I had a spare laying around...
 
problem being is i believe my check engine bulb is out....and im not sure how to fix it. im picking up a scanner tonight to check for codes. does anyone know how to replace the bulb for the CEL??
 
problem being is i believe my check engine bulb is out....and im not sure how to fix it. im picking up a scanner tonight to check for codes. does anyone know how to replace the bulb for the CEL??

My spedo stops working when the hose for my wiper fluid leaked on the sensor. Cleaned it up and it worked fine.

CEL uses the same bulbs you put in your interior lights. just pull out your console and twist in a new bulb.
 
problem being is i believe my check engine bulb is out....and im not sure how to fix it. im picking up a scanner tonight to check for codes. does anyone know how to replace the bulb for the CEL??

Lower the steering wheel and remove the gauge cluster. If I remember right, it comes out with just a couple Phillips screws (to get the trim out)and then a handful of 10mm bolts. Give it a wiggle and pull it out. The cluster bulbs simply twist out like was said above.

For the VSS, shine a flashlight down under the TB like was mentioned and look for the sensor with a single 10mm bolt holding it in place. This is what you're looking for. The connection is a snap-style, so you will have to lift up on the clip a bit before you can pull it off.

Once you have the sensor out, be sure it has the little white pinion gear on it (also stated above). If it's missing, you've got bigger fish to fry than figuring out why your speedo isn't working...
 
k, i'm having the same problem...is the pinion in the tranny down that hole that it sits down in, or should it be on the sensor when you install it? cause mine was working totally fine too until i rebuilt my motor, pulled the tranny etc.
 
It should be on the sensor when you pull it out. Just for the record, my gear was black (it was black on the replacement sensor too).
 
nothing came out...and all i saw on my existing and new sensor was some little square metal thing, almost something you COULD put a gear onto
 
so if i dont find this white or black gear, then what would the problem be? sorry for the newbie questions, im just trying to do this work myself apposed to bringin it to satan....
 
The pinion itself can come off the sensor, and may or may not come installed with a new sensor. If the pinion was not on the sensor when you pulled it from the car, either A) Somebody replaced it previously, and never put the pinion on, or B) It is inside your transmission, and you are in for a fair amount of work.

If you fear the gear is in the transmission, you should pull it off, and split it apart. Try to find all the pieces, and inspect the bearings and synchro's for damage that may have happened because of the pinion floating around. It is not as difficult as you may fear.

BTW: The gear on the last Neon I worked on was a translucent yellow color.
 
i have the same problem as the last guys..but here's my story.

i had a CEL for the speedsensor. however my speedo worked with no problems. i went ahead and had the speed sensor replaced....now i have no CEL so all is dandy....except...

now my speedo doesn't work.since i'm not getting a CEL am i wrong to assume it's not the speed sensor? just curious...i'm not sure what else to do....this kinda sucks as i was looking at selling my car wednesday.

any help is great.
 
i replaced the VSS however, i can't be certain if the gear fell off yet...but my problem was not fixed...just yea if you replace it make sure all the stuff is there...should be a small gear with the VSS
 
If the pinion is on the VSS, and your speedo and odo are not functioning, try measuring for a signal from the VSS. Remove it, and spin it while watching for a pulsed output. Pulses should become closer as it is spun faster.

If you are getting an output from the VSS, check that it is reaching the ECU. If it is not, you have a damaged wire. If it is, check for the speed signal from the ECU. If you do not get a signal from the ECU, it is bad. Again, if you have one, check the signal at the speedo harness. If you do get a signal to the speedo/odo, but they won't function, you have a bad speedometer. If you get no signal to the speedo, there is a damaged wire/connection between the ECU and speedo.

If everything checks out, eyeball the plastic ring gear on the differential, inside the VSS hole. Make sure its' teeth are not broken or worn, and using your finger, check that it is firmly attached to the differential.

That should cover about everything that could be at fault, I believe.

Hope that helps you guys.
 
Is it possible for somebody to post a pic of where this sensor is located?? im still having trouble finding this......IE i only have a driveway, no lift so Im kind of limited.

Hope someone can get a pic.....thanks guys'
 
My speedometer stopped working also. To get at the Sensor you have to remove the battery, battery shelf, and depending on how big your hands are, the mounts for the battery shelf (A.K.A you'll need a wrench and like a 14mm socket). Once all of this is removed if you look under the throttle body you will see tucked in by the rear tranny mount the speed sensor. In my case I had broken the mount and thus destroyed the sensor also. I doubt this is your issue but by any means that's how to best get at the sensor. Don't worry, you wont have to jack up the car, at least not yet. If the gear on the vss fell off you may be in a world of hurt.
 
Last edited by a moderator:
Just a quick question as I am reading this, where is the sensor on an automatic 95 GS
 
If the pinion is on the VSS, and your speedo and odo are not functioning, try measuring for a signal from the VSS. Remove it, and spin it while watching for a pulsed output. Pulses should become closer as it is spun faster.

If you are getting an output from the VSS, check that it is reaching the ECU. If it is not, you have a damaged wire. If it is, check for the speed signal from the ECU. If you do not get a signal from the ECU, it is bad. Again, if you have one, check the signal at the speedo harness. If you do get a signal to the speedo/odo, but they won't function, you have a bad speedometer. If you get no signal to the speedo, there is a damaged wire/connection between the ECU and speedo.

If everything checks out, eyeball the plastic ring gear on the differential, inside the VSS hole. Make sure its' teeth are not broken or worn, and using your finger, check that it is firmly attached to the differential.
That should cover about everything that could be at fault, I believe.

Hope that helps you guys.


I have a GST and was wondering if there is supposed to be a plastic ring gear on the differential as well because i dont have one... i just have a plastic gear on the VSS... Also is the differential supposed to turn when you spin the axels??
 
I'm having the same issue but I'm afraid that my gear fell into the transmission and i have a M/T would that cause it from going into gear
 
Im having the same problem with my 99gs right now. The plastic gear thats on the metal16g shaft fromand the sensorsensor fell into the trany and i cant get it. The trans made no noise or has any issues but speedo doeant work. Anyone know when to get that gear from.
 
Im having the same problem with my 99gs right now. The plastic gear thats on the metal16g shaft fromand the sensorsensor fell into the trany and i cant get it. The trans made no noise or has any issues but speedo doeant work. Anyone know when to get that gear from.
The dealership, a junkyard, eBay, the classifieds, someone local parting out their car...
 
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