speeodmeter and odometer

1992 GMC SONOMA
125,000 MILES • 4 CYL • 2WD • AUTOMATIC
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JESTERGMC
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My speedometer and odometer quit working. I replaced the speed sensor on trans. Checked resistance on the stepper motors in cluster. replaced cluster. Check for voltage going to speed sensor plug=0. Also traced wiring back to firewall. What else can I do?
May 7, 2011 at 9:30 AM
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JESTERGMC
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I also cleaned plug with electrical cleaner and checked for voltage at the wire and plug.
May 7, 2011 at 9:34 AM
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DOCFIXIT
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Raise rear wheels off ground place DVOM meter on AC scale trans in neutral. Rotate tires by hand @3mph meter shloud read .5 - 1 v AC
May 7, 2011 at 9:41 AM
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JESTERGMC
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Do I take the reading off the speed sensor? If it read good or bad what are the options?
May 7, 2011 at 10:49 AM
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DOCFIXIT
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Yes reading off seed sensor this will tell if signal is being produced
May 7, 2011 at 12:13 PM
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JESTERGMC
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I got readings that jumped from 0 to 1.5 but had to turn the wheels at higher speed to get anything? So what does that mean?
May 10, 2011 at 1:20 PM
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JESTERGMC
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Is there something simple that I am missing?
May 10, 2011 at 1:54 PM
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DOCFIXIT
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Find VSS buffer item F in first diagram on firewall near ECM. Check White Wire term.10 for output to speedo also check input signal from VSS
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May 11, 2011 at 6:52 AM
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JESTERGMC
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I am having a hard time finding the VSS. Is it on the engine firewall or in the cab?
May 14, 2011 at 9:43 AM
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DOCFIXIT
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Info I have firewall next to ECM
May 16, 2011 at 1:12 PM
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JESTERGMC
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Thanks. I found it and fixed it.
May 19, 2011 at 7:03 AM
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DOCFIXIT
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Great so it was VSS?
May 19, 2011 at 8:32 AM
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JESTERGMC
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It was a wire grounding out on the fire causing the brake fuse to blow. But I had brake lights the whole time.
May 21, 2011 at 6:52 AM
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DOCFIXIT
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Thanks that was an unusual fault good work finding that
May 23, 2011 at 6:42 AM
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