Sunroof Solar Panel
Sunroof Solar Panel
• Solar mode is only possible when the sunroof is either closed or in a raised position. Solar panel - C - converts solar energy into electrical energy which then passes into the vehicle electrical system via contacts - A - (on the front edge of the sunroof) and - B - (on the frame of the sunroof)).
• Solar operation is not possible when the ignition is switched on and when in auxiliary heater/auxiliary ventilation mode. The fresh air blower control module (J126) interrupts the link between the solar roof and the fresh air blower (V2).
• If fresh air blower solar mode is not desired, the function can be switched off at the Climatronic control module (J255) , or in the MMI (Multi Media Interface), refer to the Owner's Manual and Infotainment/MMI operating instructions.
• Certain A/C system functions can be switched on and off via the MMI (Multi Media Interface) under the "A/C system" function in the "car"/"car systems" menu. The A/C system control can also be influenced via presettings in the MMI (Multi Media Interface) under the "A/C system" function in the "car"/"car systems" menu. Therefore, first check the presetting in the MMI in the case of a problem with these components. Refer to Infotainment/MMI operating instructions.
• In the read measured values function of the Guided Fault Finding of the Climatronic control module, the operating time of the fresh air blower in solar mode is displayed in hours. Check using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
• Via the "adaptation" function, the temperature from which the function of the solar panel can be switched on/off can be entered in the Climatronic control module using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
• The fresh air blower control module is designed such that the fresh air blower is only actuated in solar mode if there is sufficient energy to operate the solar cells (minimum voltage with fresh air blower activated must currently be greater than 2 V).
• The solar cells must produce a voltage greater than approximately 12.3 V in order for the fresh air blower control module to connect the current generated by the solar cells of the solar panel to the fresh air blower. After the fresh air blower control module has produced a voltage greater than approximately 12.3 V, the fresh air blower is actuated as long as the solar cells continue to provide a voltage of approximately 2 volts (or the ignition, parking ventilation or parking heater is switched on).
• The energy supplied by the Solar Cells (C20) is conveyed directly to the fresh air blower via fresh air blower control module. The fresh-air blower converts the generated electrical energy into blower output.
• In vehicles without a solar panel, all A/C system control motors remain in their current position when the ignition is switched off. However, in order to ventilate the vehicle interior when the system is in solar mode, the fresh air/recirculated air door must be in the fresh air mode position. In vehicles with a sunroof solar panel, the v is therefore informed via the coding that the vehicle is fitted with solar cells. After the ignition is switched off, the Climatronic control module then moves the doors in the A/C unit to the fresh air mode position.
• With the ignition switched off (no signal detected by the Climatronic control module), the fresh air blower control module checks the voltage at the input of the solar cells in regular intervals and converts the voltage generated by the solar cells in such a way that the fresh air blower runs at the highest possible speed when there is sufficient solar energy.
• Terminals - A - and - B - (on the sunroof and sunroof frame) are used to transfer the generated electrical energy, 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).
• The electrical energy generated by the sunroof solar panel at a solar radiation level of 500 W/m2 is approximately 12 W:
Example:
500 W/m2 (solar radiation) x 0.21 m2 (solar cell surface area on sunroof) x 0.13 (efficiency of Solar Cells) x 0.9 (efficiency of fresh air blower control module).
Check The Function Of The Sunroof Solar Panel
- Place vehicle in direct sunlight.
• If the weather conditions are unfavorable, the sunroof solar panel can be illuminated using two commercially available 1000 W halogen headlamps. A distance of at least 500 mm from the sunroof solar panel must be maintained. Make sure that all sunroof Solar Cells are illuminated completely and evenly so that the Solar Cells can supply sufficient electrical energy to drive the fresh air blower,
• Only an electrical energy of approximately 1.5 W is supplied when shining halogen lamps on the sunroof solar panel (the fresh air blower turns, but air flow is difficult to detect).
• In the read measured values function of the Guided Fault Finding of the Climatronic control module, the current output of the Solar Cells (the voltage and current strength) is displayed depending on the version immediately after the ignition is switched off. Check using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
- Open the center instrument panel vents and close the remaining vents.
- Check the setting on the Climatronic control module or the MMI (Multi Media Interface). The "solar mode" function has to be set, refer to Operating instructions and Infotainment/MMI operating instructions.
- Close sunroof.
- Switch the ignition off (the Climatronic control module is dark).
A current of air can be felt from the dash panel vents (check by moistening palm of hand if necessary).
If no air flow can be detected:
- Query the event memory of the Climatronic control module and check the coding of the Climatronic control module using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
- Check the setting (and the adaptation if applicable) on the Climatronic control module and the MMI (the "solar mode" function must be activated), refer to Operating instructions, Infotainment/MMI and the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
- Move the right front seat (passenger side seat) as far back as possible.
- Switch off the ignition.
- Remove screw clips - A -.
- Loosen and remove insulation mat - B - from bracket - C -.
• There are retaining straps with hooks - A - at the glove compartment - D - that act as assembly aids, and which are installed in the noise insulation openings - B - as shown in the illustration. If the glove compartment - D - is not installed correctly (press the retaining straps with hooks - A - from underneath against the noise insulation - B -), the noise insulation - B - can only be removed if the glove compartment is already removed.
- Disconnect connector - A - from the fresh air blower control module - B -.
- Measure the voltage between contact - 2 - (from the sunroof solar panel) and contact - 1 - (ground) at connector - A -.
• Target value: greater than 12.3 V = (depending on intensity of the solar radiation)
- Connect a test lamp (12 V with maximum 5 W) between contacts - 2 - and - 1 - at connector - A -.
- The test lamp should glow or light up (depending on intensity of the solar radiation).
• The solar cells must produce a voltage greater than approximately 12.3 V in order for the fresh air blower control module to connect the current generated by the solar cells of the sunroof solar panel to the fresh air blower. After the fresh air blower control module has produced a voltage greater than approximately 12.3V, the fresh air blower is activated as long as the solar cells continue to provide a voltage of approximately 2 volts (or the ignition, parking ventilation or parking heater is switched on).
• If the test lamp glows or lights up, the function of the sunroof solar panel is OK. If the fresh air blower is not running, check the fresh air blower for ease of movement and the activation of the fresh air blower control module by the Climatronic control module. Check using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
• If test lamp does not glow or light up, check wire connection to both terminals at sunroof cut-out. If no malfunction is detected, check the solar panel.
• Only an electrical energy of approximately 1.5 W is supplied when shining halogen lamps on the sunroof solar panel (the fresh air blower turns, but air flow is difficult to detect).
• The current, which is sent from the sunroof Solar Cells to the fresh air blower, can be read in the read measured values function of the Guided Fault Finding depending on version of the Climatronic control module. Park the vehicles for example with the sunroof closed in the sun (or under two headlamps as described above) and select the particular measured value of the Climatronic control module. Check using Vehicle Diagnostic Tester in the "Guided Fault Finding" function. After switching off the ignition, the current is then displayed which was sent from sunroof with Solar Cells when switching off the ignition (and the brief period afterward).