Headlamp Alignment Sensor: Testing and Inspection
Calibration of position sensor, GDL lamps
When replacing a gas discharge lamp module (GDL) or one of the position sensors for the gas discharge lamps, the position sensors must be calibrated.
Note! The signal from the position sensors must be 1-4 V in order for calibration to be successful. Check that the values lie within the permitted limits with the help of the service "Position sensor Xenon lamp".
Hint: In conjunction with calibration of the position sensors, the gas discharge lamp modules (GDL) are also programmed with vehicle parameters.
Note! Diagnostic trouble codes (DTCs) CEM-8A20 and CEM-8A21 are stored when replacing with a new gas discharge lamp module (GDL). After calibrating the position sensor, the diagnostic trouble codes (DTCs) in the central electronic module (CEM) are erased.
- Ensure that the car is unladen and is on a flat surface
- Ignition on
- Click the VCT2000 symbol to calibrate the position sensors.
Was Calibration Sucessful?
Yes - Reading and erasing diagnostic trouble codes (DTCs)
No - Communication fault
-------------------------------------------------
Reading and erasing diagnostic trouble codes (DTCs)
- Ignition on.
Check the calibration of the position sensor by reading off the diagnostic trouble codes (DTCs).
If diagnostic trouble codes (DTCs) CEM-8A20 and CEM-8A21 have been stored, the calibration has failed.
Click the VCT2000 symbol to read diagnostic trouble codes (DTCs).
Continue - Troubleshooting procedure complete
Numeric Result 0 - Communication fault
-------------------------------------------------
Communication fault
Communication has been interrupted for one of the following reasons:
- The ignition is switched off
- VCT2000 disconnected from the data link connector (DLC)
- VCT2000 disconnected from the VIDA cart
- Communication problems in VIDA application or in car.
- No voltage in the data link connector (DLC).
Check therefore:
- That the control module power supply and ground terminal are fault-free.
- That the fuse for the data link connector (DLC) is intact.
- that the ignition is on
- that the battery voltage (system voltage) is normal (approximately 12 V).
If necessary a battery charger can be connected during the test.
For information about charge currents and the battery, see: Battery, charging Battery, Charging
- that VCT2000 is correctly connected to the VIDA cart and the data link connector (DLC)
- that VCT2000 and the wiring is fault-free.
Other information
- For information about fuse and terminal numbers, see the relevant Wiring Diagram.
Try to establish communication again or exit reading off diagnostic trouble codes (DTCs). Depending on the communication fault, select one of the following options.
1. Try again
2. Fault-trace more comprehensively for the communication problem that has occurred
3. Exit fault-tracing / Read off from the next system.
Which alternative is requested?
1. Attempt new test
2. Checking communication
3. Exit fault-tracing
-------------------------------------------------
Checking communication
Checking communication errors
Hint: Test the communication with another corresponding vehicle to decide if the malfunction is in the vehicle or in VIDA/VCT/cable harness. If the communication works on another vehicle, the malfunction is in the vehicle.
Hint: For current information about each circuit and signals, see wiring diagram and signal description for each system.
Diagnostic outlet
- Check the voltage feed to diagnostic outlet #16. The voltage shall match battery voltage.
- Check the cable for power ground and signal ground to diagnostic outlet #4 and #5.
Hint: When VCT2000 is connected to the diagnostic outlet (is supplied with voltage), the indicator diode shall be activated with a green light. Then the indicator diode flashes quickly when communication takes place with a control module. In case of certain internal malfunctions on VCT2000 the indicator diode is activated with a red light!
Communication cables
- For communication problems with control units on the high-speed network, check communication cables between diagnostic outlet #6/ #14 and central electronic module (CEM) #B11/ #B12 for open circuit, short-circuit to ground and short-circuit to voltage according to references above.
- For communication problems with control units on the low-speed network, check communication cables between diagnostic outlet #3/#11 and central electronic module (CEM) #B16/#B15 for open circuit, short-circuit to ground and short-circuit to voltage according to references above.
- Also check the communication cables for the low and high-speed net between the central electronic module (CEM) and the other connected control modules according to troubleshooting above.
Control modules
- Check that the control module's voltage feed and ground connection are trouble-free.
Caution! If none of the above checks help, try reading out diagnostic trouble codes in the central electronic module (CEM). Done via VIDA vehicle communication. A prerequisite for being able to communicate with the control modules in the vehicle is that the central electronic module (CEM) is active and can be communicated with. If communication is not possible with the central electronic module (CEM), check the voltage feed and ground for the central electronic module (CEM).
VCT2000 and cable harness
- Connect VCT2000 to the vehicle so that it is supplied with voltage. Test VCT2000 by selecting the system's self-test and VCT Test in the VIDA main menu. If any malfunction is found according to the test, first replace the cable harness then the VCT2000, if the test still indicates a malfunction.
- If no malfunctions were found after troubleshooting according to above, try with a new cable harness and/or new VCT2000.
VIDA
- If no malfunctions were found after troubleshooting according to above, try performing a complete system reset of VIDA.
Other information
- Checking wiring and terminals Checking Wiring and Terminals
Continue - Fault-tracing information
-------------------------------------------------
Fault-tracing information
Fault-tracing communication problems is now finished.
Do you want to try establishing communication again?
Yes - Attempt new test
No - Exit fault-tracing
-------------------------------------------------