Tech Question: PCM Functions

[Earl_H]

I have found that the stock pcm controls voltage regulation. Does it also interface with the speedometer and vehicle speed sensor.

 

[ViperJohn]

I know it interfaces with the speed sensor. I believe that is how it receives vehicle speed info.

I think the speedometer operates off the rear end and is not connected to the PCM. (But not 100% sure about this.)

 

[PhoenixGTS]

I have found that the stock pcm controls voltage regulation. Does it also interface with the speedometer and vehicle speed sensor.

Yes - thus creating the opportunity to run the little gear ratio correction boxes sold to give you the right speedometer reading after you change gears. Pins 27-28 on the white PCM connector.