Cruise Actuator Inspection

WARNING: This page is about a different car, the 2005 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the cruise actuator connector.
Disconnect the actuator cable from the cruise actuator.
Start the engine and run it idle.
Confirm that the diaphragm is drawn into the cruise actuator when battery positive voltage is connected to terminal C and terminals A, B and D are connected to the ground.

Fig 1: Identifying Battery Positive Voltage Is Connected To Cruise Actuator Terminal C And Terminals A, B And D Are Connected To The Ground
Courtesy of MAZDA MOTORS CORP.
With the diaphragm being drawn into the cruise actuator, confirm that the diaphragm returns to its original position when terminals B and D are disconnected from the ground.

Fig 2: Identifying Cruise Actuator Terminals B And D Disconnected From Ground
Courtesy of MAZDA MOTORS CORP.
With the diaphragm returning to its original position, confirm that the diaphragm stops moving when terminal D is reconnected to the ground.

Fig 3: Identifying Cruise Actuator Terminal D Disconnected From Ground
Courtesy of MAZDA MOTORS CORP.
With the movement of the diaphragm stopped, confirm that the diaphragm returns completely to its original position when all terminals connected to the ground are disconnected.
- If not as specified, replace the cruise actuator.
  
  Fig 4: Identifying All Cruise Actuator Terminals Disconnected From Ground
  Courtesy of MAZDA MOTORS CORP.