Hello,

I have a 2003 F150 Supercrew with the 6CD In-Dash changer. From what I've read online I should have a VSS wire in the factory harness for the stock audio volume control. Supposedly it's grey/black. It doesn't seem to be there. The only wire in the factory harness I'm not using is red/black and it seems to put out 0 volts in park/neutral but 4.45 volts in reverse or drive, however it doesn't fluctuate with speed. Is this the wire I'm looking for? Thanks for the help, this seems to be the only thing holding up my F90BT install.

its not in the main harness with the power and speaker leads, but the other square harness that was also plugged into the radio.

Do you know which pin it is? I still don't have a gray/black wire in the second harness, it has 20 pins there are 8 wires. I checked them all on A/C this time as I read online that it's an A/C signal. 7 wires registered .010V-.030V driving from 0-30 or so, the other one a green/black one registered .010V-.060V driving 0-30 and did seem somewhat linear to speed.