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Speedo not working, transmission will not shift out of first

2K views 1 reply 2 participants last post by  AstroWill 
#1 ·
sensor wire 1.jpg
I am posting this to help others diagnose their van, I have purchased a 2005 Astro Cargo Van with 175k miles on it.
A week after we got it, the speedo bounced around a bit a for a day and shifted like it was uncertain of what gear to be in.
next day it would not shift out of first and the speedo was not reading.

The Vehicle speed sensor is located on the pass side of the transmission on the rear tail extension, (2wd)
the two wire plug a few inches up the loom also has a bare wire, this is normal and the way it should be.
a little further up this loom that goes over the transmission these wires are wrapped in a special shielded wrapping all the way to the ECM.
These two wires do no go to a vss buffer or similar, they go directly from the sensor to the ECM to the drivers side plug of the ECM in the engine bay.(up through the loom beside the transmission, over the top of the rear of the engine, along the passenger side of the engine then loops over the top in the engine bay to the ECM)
I was certain there was a break in the wires somewhere, but the break was at the plug that went to the sensor itself.
I believe broke due to movement over the years.

The outer case of the wire was completely intact showing no indications of the inner wire being broken.
I bought a new wiring pigtail off Amazon for $10 soldered it on and shrink wrapped it and put it in new wiring loom and zap strapped the wiring to the bracket beside the sensor so this will never happen again.

Mike
 

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