Novak Conversions Jeep Wrangler YJ engine mounts

Speedometer not working

bobbyk3

New Member
Joined
Feb 23, 2025
Messages
9
Location
Clovis Ca.
1995 Wrangler with Teraflex Extreme Short Shaft SYE. Speedometer stopped working a few days ago. Replaced the VSS and still doesn't work. Took the dash apart and inspected the speedometer ribbons and they look clean (see pic). Where do I go from here??

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I will, but how would that affect the VSS?

The super short SYEs delete the speedo gear and go with a tone ring and the pickup sensor instead. The tone ring can become loose and spin if the nut isn’t tight enough. You wouldn’t think that happens often but I’ve seen it mentioned quite a bit over the years. If that doesn’t fix it then you may have a short in your wiring somewhere up the line.
 
The super short SYEs delete the speedo gear and go with a tone ring and the pickup sensor instead. The tone ring can become loose and spin if the nut isn’t tight enough. You wouldn’t think that happens often but I’ve seen it mentioned quite a bit over the years. If that doesn’t fix it then you may have a short in your wiring somewhere up the line.

Appreciate it! I'll check that nut then. I DID just put in a new transmission output shaft seal a couple weeks ago, so maybe it didn't get tight enough.
 
The super short SYEs delete the speedo gear and go with a tone ring and the pickup sensor instead. The tone ring can become loose and spin if the nut isn’t tight enough. You wouldn’t think that happens often but I’ve seen it mentioned quite a bit over the years. If that doesn’t fix it then you may have a short in your wiring somewhere up the line.

Should I also pull the plug to the speedo/tach cluster and check and see if I'm getting voltage to the #13 pin? I believe that's the pin to the speedo.
 
Should I also pull the plug to the speedo/tach cluster and check and see if I'm getting voltage to the #13 pin? I believe that's the pin to the speedo.

You could. I think you’ll see 5V there and I believe that splices off the PCM. So I’m not sure verifying 5V there really tells you much, but maybe. It’s been a while, I don’t really remember how the speed sensor works.

edit: I went back and reminded myself how it works. PCM supplies 8V sensor power and ground on the orange and black wires going to speed sensor. The orange/white wire is the wire that the sensor pulses to provide feedback back to the PCM, instrument cluster, and DRL module if equipped (Canada).

To verify your wiring is good, you would want to check continuity on the orange/white wire from the cluster to the speed sensor, and you’d want to verify that wire has no continuity to ground. As long as those are both the case, then it isn’t the wiring. For whatever reason, checking voltage on that wire shows 5V or it always did for me at least. I don’t know why, the power source is 8V provided by PCM. No clue why the power after it goes through the sensor comes out as 5V on the orange/white wire.
 
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You could. I think you’ll see 5V there and I believe that splices off the PCM. So I’m not sure verifying 5V there really tells you much, but maybe. It’s been a while, I don’t really remember how the speed sensor works.

edit: I went back and reminded myself how it works. PCM supplies 8V sensor power and ground on the orange and black wires going to speed sensor. The orange/white wire is the wire that the sensor pulses to provide feedback back to the PCM, instrument cluster, and DRL module if equipped (Canada).

To verify your wiring is good, you would want to check continuity on the orange/white wire from the cluster to the speed sensor, and you’d want to verify that wire has no continuity to ground. As long as those are both the case, then it isn’t the wiring. For whatever reason, checking voltage on that wire shows 5V or it always did for me at least. I don’t know why, the power source is 8V provided by PCM. No clue why the power after it goes through the sensor comes out as 5V on the orange/white wire.
Looks like the VSS is good. Can't post the video, but it alternated between these two signals as I spun the drive-line slowly. What now? Where else does this signal wire go to other than the PCM?

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I just started having the same issue, and thought that the issue is/was the small pin that holds the tone ring in place. I found it had slipped out and reinstalled everything. It worked for a few days, but just started slipping again after going on the interstate at higher speeds. Is there anything that can be done to keep the pin from slipping out? the teraflex extreme short shaft kit uses this to hold the tone ring rather than being pressed into place or being held tight by the output shaft nut. (although I'm sure that the nut is supposed to keep the tone ring from slipping off the shaft pin. it seems to me that the pin is too short, that the slot in the tone ring has room for the pin to slip completely out of the hole in the output shaft. Wondering if anyone has had this issue and found the cure? Possibly a slightly longer pin for the tone ring?
 
Novak Conversions Jeep Wrangler YJ engine mounts