Speedometer Stopped
05-31-2017, 09:19 AM
#1
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Speedometer Stopped
Guys,
Here is a head scratcher that I can't figure out. I have a 2000 auto convertible. I drove it since March 2016 and the speedo worked just fine. Over the winter I replaced the tired out LS1 with a 6.0L at a friends house. Drove the car back to my place in March 2017 and the speedo still worked. I pulled the trans in April to have it rebuilt. At that point my friends and I noticed that the sensor at the top of the diff had been cut by a previous owner. From what I can gather that is the VSS/vehicle speed sensor. Now that everything is put back together, the speedo on the dash, the speedo on the HUD, and the mpg digital readout don't work. Seems like the trans wants to hold first gear for a longer time too.
Question is - based on what I've read on this site, I never should have had an operable speedo in the first place with the VSS wires cut. 1) How did it work up to the trans rebuild? 2) How can I remedy this? I've seen no wiring under the car that the VSS would plug into. If I find where it leads to is it as simple as running fresh wire to re-establish the connection?
I haven't had time to pull codes but I can do it tonight after work.
Any thoughts or ideas would be appreciated.
Here is a head scratcher that I can't figure out. I have a 2000 auto convertible. I drove it since March 2016 and the speedo worked just fine. Over the winter I replaced the tired out LS1 with a 6.0L at a friends house. Drove the car back to my place in March 2017 and the speedo still worked. I pulled the trans in April to have it rebuilt. At that point my friends and I noticed that the sensor at the top of the diff had been cut by a previous owner. From what I can gather that is the VSS/vehicle speed sensor. Now that everything is put back together, the speedo on the dash, the speedo on the HUD, and the mpg digital readout don't work. Seems like the trans wants to hold first gear for a longer time too.
Question is - based on what I've read on this site, I never should have had an operable speedo in the first place with the VSS wires cut. 1) How did it work up to the trans rebuild? 2) How can I remedy this? I've seen no wiring under the car that the VSS would plug into. If I find where it leads to is it as simple as running fresh wire to re-establish the connection?
I haven't had time to pull codes but I can do it tonight after work.
Any thoughts or ideas would be appreciated.
05-31-2017, 06:36 PM
#2
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
You MUST have the VSS on top of the DIFF connected for the SpeedO to work. That is the C5/C6 sensor for vehicle speed.
Here is the PATH for the VSS / Speedo. Notice it IS NOT a direct path and the signal comes from the PCM to the IPC via a digital signal on the STAR Buss Serial Data Line:
Here is the PATH for the VSS / Speedo. Notice it IS NOT a direct path and the signal comes from the PCM to the IPC via a digital signal on the STAR Buss Serial Data Line:
05-31-2017, 06:44 PM
#3
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
I have the other schematic from the VSS to the PCM but I have to find it...
Bill
Bill
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ClevelandTim (05-31-2017)
06-01-2017, 01:09 PM
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
This scmatic represents how ALL the digital signals get to the IPC for all the gauges. ALL of the gauges (except the volt meter) are not directly connected to a sensor. The sensors connect to the PCM and the PCM sends the digital signals get to the IPC via the serial data buss:
I still need to find the schematic with the VSS circuit.
Bill
I still need to find the schematic with the VSS circuit.
Bill