Vss signal loss issue

I also opened up the wire harness from sensor all the way to the front t of truck ro make sure there was no breaks or bare wires anywhere.
 
OK, that's what I was trying to establish, to me it sounds like the Megasquirt is picking up "noise" in the system that the PSOM is successfully filtering. You said there had been a repair done to the harness at some point?
 
I only see tunes, do you have a datalog? If so can you upload it somewhere that I can download? I don't want to enable that file format for the forum as it will kill our storage.
 
You can definitely see the spikes in VSS, but it's odd though as they only seem to happen when the vehicle is stopped once you get moving it's smooth. I did see where Stinger said they'd replace the unit which is awesome of them. I'm not convinced that's the problem though, but only one way to tell.

Tonys Weirdness.JPG
 
Figured I would try that out and see if it makes a difference. I tried looking through the different speed sensor settings in ts and don't see anything odd there. Was think maybe something was set wrong
 
Yes. I'm not sure what's the deal. Tried test all wires and doing the test like Steve posted and everything is looking good. I even went through and found all the ground location for the major components like g200, g100, driver kick panel, battery to fender to frame to engine block and cleaned everything up. I checked pin 20 ecu ground pin 6 vss ground. Tested at the test plug and at pin 3 on ecu doing 0-30. Just weird that this is happening especially at the mph that it is
 
I also tried unplugging cruise control and rabs module to see if that would change thing and still the same result
 
Have you had your alternator tested? It generates an AC signal that is converted to DC by a rectifier bridge using diodes. If one of the diodes fails it will send an AC signal that could confuse things when you are stopped and the VSS is no longer sending a signal. Once you are moving the VSS signal washes out the alternator.
 
In this pic of how the vss connector is what side should have the light green/blue wire and what side should have the red/pink wire. I'm still trying to confirm that the wire are placed in the connector right
 

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alarcont91 said:
In this pic of how the vss connector is what side should have the light green/blue wire and what side should have the red/pink wire. I'm still trying to confirm that the wire are placed in the connector right
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Look back at Steve's post, it shows the pinout for connector C404
 
Interesting must be a difference in years, unfortunately my book does not show the C404 connector pin out

70662385921be09a8b83e8b867549ae9.jpg
 
That's what stumping me is the diagrams are vague and don't show a connector orientation with the correct color wire our trucks have.
 
I was hoping someone had a pic or could get a pic of the connector on their truck to show exactly how the wire are pinned in to make sure mine is correct.
 
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