Speedo quit working
Thread Starter
Melting Slicks
Joined: Aug 2000
Posts: 2,381
Likes: 42
From: Murrysville PA
Speedo quit working - UPDATE
So here's the problem of the week. No speedo signal at the dash or ECM. So I pull the VSS and it looks good. I looked in the VSS hole and the teeth on the worm gear look good. However, I can spin the worm gear with my finger. I've never had the tailshaft off before but I would think thar the worm gear should not spin. Anyone know this before I pull the tailshaft?
UPDATE:
I had a closer look this AM and the drive gear is NOT spinning on the output shaft. It must have felt that way when I was attempting to turn it. Also my VSS is generating an output voltage so the problem is between the speed sensor and the dash.
And to think for a minute I thought this was going to be easy!
UPDATE:
I had a closer look this AM and the drive gear is NOT spinning on the output shaft. It must have felt that way when I was attempting to turn it. Also my VSS is generating an output voltage so the problem is between the speed sensor and the dash.
And to think for a minute I thought this was going to be easy!
Last edited by 89vette; Jul 11, 2011 at 08:31 AM.
Burning Brakes
Joined: Sep 2008
Posts: 810
Likes: 58
From: Alva Florida
You can check the pulse of the VSS with a multimeter. I checked mine and it will register a pulse signal. I used plastic jumper connectors from the speedo wires out of the transmission to make long wires I could use to test, jacked up the car, set the rear on the frame on jackstands and got the tires up to what would be maybe 5-8 mph. The VSS registers a signal in the smallest of measurments I believe of voltage, but cant remember. Google "How to test a Vehicle speed sensor" and it will tell you how to set your multimeter.
My VSS puts out, but my speedo doesn't work...wish I could figure out why too...
Good Luck!
My VSS puts out, but my speedo doesn't work...wish I could figure out why too...
Good Luck!
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 7
From: Tampa Florida
So here's the problem of the week. No speedo signal at the dash or ECM. So I pull the VSS and it looks good. I looked in the VSS hole and the teeth on the worm gear look good. However, I can spin the worm gear with my finger. I've never had the tailshaft off before but I would think thar the worm gear should not spin. Anyone know this before I pull the tailshaft?
UPDATE:
I had a closer look this AM and the drive gear is NOT spinning on the output shaft. It must have felt that way when I was attempting to turn it. Also my VSS is generating an output voltage so the problem is between the speed sensor and the dash.
And to think for a minute I thought this was going to be easy!
UPDATE:
I had a closer look this AM and the drive gear is NOT spinning on the output shaft. It must have felt that way when I was attempting to turn it. Also my VSS is generating an output voltage so the problem is between the speed sensor and the dash.
And to think for a minute I thought this was going to be easy!
Thread Starter
Melting Slicks
Joined: Aug 2000
Posts: 2,381
Likes: 42
From: Murrysville PA
Thank you. Maybe it has something to do with my tach's erratic signal too even after replacing the tach filter. I suspect it's the connector that plugs into the right side of the gauge cluster.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 7
From: Tampa Florida
Speedo and tach connections @ the cluster are in the same connector (the larger of the 2).
Check the ground cables (- battery cables) lug(s) on the engine block (big wire directly bolted to the block above the oil temp sender) and on the tranny bell housing to ensure that they are good-n-tight. Loose grounds will sometimes give you wacky problems such as your mentioning. Keep us posted.
Last edited by engle1147; Jul 11, 2011 at 12:55 PM.
