Reading off input and output signals, CEM

This function can be used to continuously read off the values and status of the control module's input and output signals.

The following parameters can be read off:

• the status of the relay for extended X supply. The relay controls the power supply for the following functions: parking heater, power driver's seat and "after blow" for the air conditioning (A/C) system. The relay is activated in key positions I, II and III when the drivers door is opened (10 minutes), driver's door is closed and key position 0 (1 minute) and when one of the above functions is activated
• the status of the relay for extended X2 supply (AUT). Controls the power supply to the gear selector module (GSM). The relay is activated in key positions I, II, III, 0 or out for 10 seconds
• the status of the relay for the park neutral position (PNP) switch
• the status of the relay for the starter motor (activation signal from the central electronic module (CEM) to the relay)
• the status of the relay to raise the rear left-hand window. The relay is only active when the window lift mechanism is operated via the switch in the driver's door
• the status of the relay to lower the rear left-hand window. The relay is only active when the window lift mechanism is operated via the switch in the driver's door
• the status of the relay to raise the rear right-hand window. The relay is only active when the window lift mechanism is operated via the switch in the driver's door
• the status of the relay to lower the rear right-hand window. The relay is only active when the window lift mechanism is operated via the switch in the driver's door
• the status of the relay for the child lock (blocks operation of the rear window lift mechanisms). Note that when the function is activated, (i. e. the LED lit), the relay which supplies the rear window lift mechanisms is not activated. The read off gives the status of the relay
• status of the relay for high beam
• status of the relay for low beam
• status of the spot lamp relay
• status of the parking lamp relay
• status of the relay for the daytime running lamps
• status of the relay for the front fog lamps
• status of the relay for the windscreen wipers, off or on
• status of the relay for the windscreen wipers, high speed
• status of the relay for the washer motor
• status of the relay for the headlamp washer
• status of the relay for the horn
• status of the power supply (S-, X-, 15-, 50- and 30-supply)
• status of the key position
• status of the L signal (from the generator (GEN)). Ignition on ~0V, engine running ~1v
• status of the confirmation from the gear-shift position sensor about whether start (starter motor relay activated) is possible
• the status of the frequency signal from the engine control module (ECM) for the fuel pump (FP) relay
• the status of the windscreen washer reservoir level
• the status of the windscreen wipers
• the status of the driver's door (open or closed)
• the status of the passenger door (open or closed)
• the status of the left rear door (open or closed)
• the status of the right rear door (open or closed)
• the status of the tailgate (open or closed)
• the status of the lock switch for the driver's door (from the driver door module (DDM))
• the status of the lock switch for the passenger door (from the passenger door module (PDM))
• the status of the lock switch for the left-hand rear door
• the status of the lock switch for the right-hand rear door
• the status of the signal from the relay switch for the fuel pump (FP)
• the status signal from the supplemental restraint system (SRS) module indicating whether the Airbag is OK
• the status of the switch for the hazard warning signal flasher
• the status of the button lamp for the hazard warning signal flashers
• the status of the key ring lighting
• the status of the indication LED for the alarm
• the status of the fuel pump (FP)
• NOTE:

  The seat belt switches are connected to the Supplemental Restraint System Module (SRS) on model year 2003 and onward. They cannot then be read from the Central Electronic Module (CEM).

• the voltage of the seat belt switch, driver's side
• the voltage at the seat belt switch, passenger side
• output, pulse width modulated signal to the courtesy lighting
• speed signal (for accessories). If the car is raised for this read off, ensure that the wheels are stationary when the gear selector is moved to position P (automatic transmissions). Note that diagnostic trouble codes (DTCs) may be stored in the ABS system if the front wheels are stationary and the rear wheels rotate
• the status of the pulse width modulation (PWM) signal for headlamp beam height control
• the status of the pulse width modulation (PWM) signal from the left-hand Xenon lamp (65%-90%)
• the status of the pulse width modulation (PWM) signal from the right-hand Xenon lamp (65%-90%)
• the fault status for the xenon lamp
• the status of the infotainment relay.