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Anyone know what this means? I had an intermittent check engine light twice today, pulled the codes and this is what I got. What is it and how do I fix it? Thanks, Tom :?:
 

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What is your speedometer doing - is it registering properly?

My speedo needle was jumpy for a long time and then finally the cable broke setting the ECM code. Ordered a new cable from St. Charles and it's worked fine ever since.

Other than that, I don't know why the code would be set, the sensor is in the speedo cluster and it 'could' be bad?

Cheers,
 

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On the manual tranny 2.8 90' Trooper, the only thing mounted at the output shaft is the speedometer cable. The speed sensor is mounted on the driver side kick panel under the dash. It's a square electronic box.

Looking at a diagram in a Haynes manual, it seems that the speed sensor on this engine (not a rotating assembly) is driven by the alternator. I guess that is where it gets it's speed signal from and then feeds a signal to the ECU. But what does the ECU do with that signal? It has nothing to do with the speedometer on this vehicle as far as I can tell. The speedometer cable goes from the tranny directly to the speedometer.
 

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tomshell said:
Anyone know what this means? I had an intermittent check engine light twice today, pulled the codes and this is what I got. What is it and how do I fix it? Thanks, Tom :?:
Is your speedo needly "wiggly"? If so, that'll set a VSS code. See my message above this one for a link to the other thread with VSS info........ed
 

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Ed Mc. said:
The VSS sensor on the 2.8 V6 is in the speedo head, it's turned by the cable. I just posted some VSS info in your "2.8" thread, check it out:

https://forum.planetisuzoo.com/viewtopi ... 3&start=25
I am looking at the vehicle speed sensor in my Trooper, and it is mounted on the driver side kick panel, not on the speedometer. I pulled the speedometer first and didn't see it there, then noticed as I was putting it back together that it is mounted on the kick panel. And the diagram I have shows that it is driver by the alternator. Edit: The vehicle speed sensor buffer is mounted on the driver side kick panel, not the speed sensor. But parts places call the buffer a 'vehicle speed sensor', which it is not.
 

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Ed Mc. said:
tomshell said:
Anyone know what this means? I had an intermittent check engine light twice today, pulled the codes and this is what I got. What is it and how do I fix it? Thanks, Tom :?:
Is your speedo needly "wiggly"? If so, that'll set a VSS code. See my message above this one for a link to the other thread with VSS info........ed
No. My speedometer works fine. No jumpiness. This vehicle speed sensor works different than the type mounted on the speedometer. And it seems to be the same for both automatic and manual transmissions for this vehicle (1990 2.8 Trooper).
 

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snoozer said:
Ed Mc. said:
tomshell said:
Anyone know what this means? I had an intermittent check engine light twice today, pulled the codes and this is what I got. What is it and how do I fix it? Thanks, Tom :?:
Is your speedo needly "wiggly"? If so, that'll set a VSS code. See my message above this one for a link to the other thread with VSS info........ed
No. My speedometer works fine. No jumpiness. This vehicle speed sensor works different than the type mounted on the speedometer. And it seems to be the same for both automatic and manual transmissions for this vehicle (1990 2.8 Trooper).
I beg to differ! The sensor is located in the speedometer head. It sends a signal to the Speed Buffer module in the driver's kick panel. The purpose of the speed buffer is to smooth out the signals from the VSS, which then go to the ECM.

So if yours continues to set a code without a "wiggly" speedo needle, you may have something wrong with the VSS sensor in the speedo head, the speed buffer, or related wiring. Use the VSS troubleshooting chart I posted in your thread, it might help. Cheers......ed
 

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Ed, I made a dumbass mistake. :oops: I misread the wiring diagram AND didn't know that the speed sensor circuit consists of a buffer fed by the speed sensor inside the speedometer. You posted some good info on the vehicle speed sensor back in 2008. https://www.planetisuzoo.com/viewtopic. ... ircuit+vss

The little gold colored box on the driver side kick panel is the buffer, not the sensor. Why every parts place that carries the 'vehicle speed sensor' for these Troopers isn't call it what it is beats me.

https://www.rockauto.com/en/moreinfo.ph ... 51&jsn=357
https://www.autozone.com/engine-managem ... 75_0_20285

Apologies for my confusion.
 
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