• Most modern vehicles utilize computer systems that maintain and operate different functions within the in-vehicle networks. These computers may be responsible for the function and timing of everything in the vehicle that's electrically charged, from the battery to the electromechanical elements such as the distributor and alternator. In order for these computers to work properly however, they must maintain certain protocols within the vehicle's network that help the computer to prioritize and deliver commands to specific elements of the vehicle on a timed basis. Ford's Standard Corporate Protocol (SCP) is an adaptive protocol system that is interfaced between the vehicle's computer and a host computer, allowing interactions between the host computer and the vehicle's mainframe network.
  
  

OBD-11

• This protocol is one of the industry standard protocols, especially since the onset of emissions control mandates and testing. This protocol is used to allow the vehicle's computer to recognize that a host computer has been connected to it through the adapter port in order to collect emissions information. As the vehicle is running, the computer not only monitors and regulates the amount of oxygen being pulled into the engine through the intake but also monitors the amount of carbon dioxide leaving the engine through the exhaust. This information is then transferred to the connected diagnostic equipment through the connector port using the OBD-11 protocol.
  
  

J1850

• J1850l has been another basic industry standard ever since vehicles were equipped with the technology to sense collisions internally and to deploy different passenger protection systems in response. The protocol is used by the computer to relay the information given when a vehicle's internal sensors have signaled that at least part of the vehicle has been in a collision. Within a fraction of a second, the protocol determines if the impact is enough to allow the deployment of personal protective equipment within the vehicle's cab to protect any passengers. Almost any vehicle that has one or multiple airbags has this protocol in its mainframe as a standard safety measure.
  
  

Can Protocols

• CAN protocols are a part of Ford SCP protocols and are in control of various aspects of the vehicle's functions relating to the vehicle's current movement. CAN protocols manage issues such as traction control and automatic 4-wheel-drive. These protocols, however, are usually not found in the SCP diagnostics of older (2003 or earlier) makes and models.