Feb 102015
 

The diagnostics implemented in the control unit CFC 208F allow the testing of the inputs:

  • rev sensor from rev counter module
  • clutch disk speed sensor (gearbox primary)
  • car speed from CAN line (through A.B.S.)

This consists in checking whether or not there is the signal.
The diagnostics on the analog input signals is made checking these type of failures:

  • signal out of electrical range
  • signal out of dynamic range

The diagnostics implemented on the output controls of the control unit CFC 208F concern:

  • the three proportional solenoid valves
  • the two on-off solenoid valves
  • the two relays (hydraulic pump and engine start enable)

The types of failures checked are:

For proportional solenoid valves:

  • short circuit to earth
  • short circuit to +Vbatt
  • circuit open

For ON/OFF solenoid valves:

  • short circuit to earth

Electric pump relay:

  • circuit open
  • short circuit to +Vbatt
  • Start-up enable relay
  • short circuit to earth
  • circuit open

These input signals and output commands are excluded from the diagnosis:

  • brake pedal (except permanent closed circuit for a certain time with car moving)
  • automatic mode (CITY) and door open switches
  • the signals supplied by C.C.M. on CAN network
  • diagnostics serial line (K)
  • signals :key (+15/54) power supply (+30) direct from battery.
 Posted by at 8:45 pm