Solar Sunroof, Electrical Testing
NOTES:
- The solar ventilation function only works when the sun roof is either closed or in the raised position. The solar sunroof converts solar energy into electrical energy which then passes into the vehicle electrical system via terminals -A- (on the front of the sunroof) and terminals -B- (on the frame of the sunroof)
- When the ignition is switched on and the auxiliary heater or auxiliary ventilation is operating, the solar ventilation function cannot be used (solar cell separation relay -J309- switches the voltage supply for fresh air blower -V2- from solar cells -C20- to terminal 30) See "Electrical Wiring Diagrams".
- The A/C control head -E87- receives its voltage supply only via terminal 15, which means that when the ignition is switched off all the positioning motors remain in their current positions.However in order to ventilate the vehicle interior when the system is in solar ventilation mode, the fresh air/recirculated air flap must be be in the "fresh air" position For this reason, on vehicles with a solar sunroof, the solar cell separation relay -J309- continues to supply the A/C control head -E87- with power for a pre-defined period after the ignition has been switched off (maintained voltage supply)
- The energy yielded by solar cells -C20- is converted by the control module for solar operation -J355- (located between the sunroof lining and the solar sunroof): for example, from 65 volts and 2.5 amps into 3.5 volts and 4.6 amps.
- The electrical energy yielded by the solar sunroof when exposed to a solar irradiation level of 500 W/sq m is around 12 watts.
- (500 W/sq m (solar irradiation) x 0.21 sq m (solar cell surface area on sunroof) x 0.13 (efficiency of solar cells -C20) x 0.9 (efficiency of control unit -J355-).
- Terminals -A- and -B- (on the sunroof and sunroof frame) are used to transfer the electrical energy generated, and must always be clean and free of conventional lubricating grease.
- If necessary terminals A- and -B- can be lightly coated with contact grease (electrically conductive protective lubricant available from suppliers of electronic equipment).
Testing operation of solar sunroof
- Park vehicle in sunlight.
NOTES:
- If weather conditions are unfavorable, the solar sunroof can be illuminated using two commercially available 500 W halogen lamps. These must be set up at a distance of at least 500 mm (19.7 in.) from the surface of the solar sunroof.
- If the solar sunroof is illuminated using halogen lamps, the electrical energy yield will be only around 1.5 watts (fresh air blower fan rotates but the air flow is hardly detectable).
- Set air conditioner so that air is directed to instrument panel air outlets.
- Open center instrument panel air outlet and close all other outlets.
- Switch ignition off (A/C control head -E87- goes dark).
- Make sure sunroof is closed.
Air should be flowing from the instrument panel air outlets (if necessary, check by moistening hand and holding in front of vent).
If fresh air blower -V2- does not work:
- Open sunroof about 10 cm (3.94 in.).
- Connect test lamp (12 V, maximum 5W) between two terminals -A- on sunroof.
The test lamp should glow or light up (depending on the intensity of the sunlight). If the test lamp glows or lights up, the solar sunroof is functioning properly.
- Check wiring to fresh air blower -V2- (via solar cell separation relay -J309-). See "Electrical Wiring Diagrams".
NOTES:
- If a signal tone is sounded by the control module for solar operation -J355- during the day (with sun radiation), a short circuit is indicated.
- Check wiring harness connection between control module for solar operation -J355- and -E- contacts for short circuit.
- Check both -E- contacts for short circuit to sun roof (-F-).
- Check fresh air blower -V2- for short circuit (using solar cell separation relay -J309). See "Electrical Wiring Diagrams".
- Insulating discs -C- and -D- must be installed between screws -A-, -B- and contact -E-.
- If there is a short circuit between contract -E- and the sunroof (-F-), a fabric adhesive tape must be placed on the contact surface -G-. The adhesive tape should be pierced carefully at holes -H-.