(Notes On Fuel Cell System - AH00.00-P-0022-01RFW)

Model 253.992/993 

General information on fuel cell system 

• There are no dangers to be expected from appropriately handling the fuel cell system and its modules or components (fuel cell stack, fuel tank, etc.)
• The use of parts coated with talcum is not permitted.

  Stop plugs and protective hoods are available as a special tool. Multiple use of the protective hoods is not permitted; clean stop plugs very well before reusing them.

• Ensure utmost cleanliness during repair work.

  Ingress of the smallest of dirt particles can damage the fuel cell system and its component parts or cause leakages. Therefore:

  1. Use lint-free cleaning cloths.
  2. Only use approved repair materials.
• Wear suitable personal protective equipment.
• Certain operations must always and only be performed outside (e.g. emptying fuel system, inerting fuel tank, flushing fuel system).
• The "Requirements for driving into the workshop" described in the workshop literature must be fulfilled.
• If there are indications of leaks and problems with the fuel cell system, secure fuel cell vehicle and park outdoors. When doing so, absolutely ensure that there is sufficient safe distance from neighboring buildings and surrounding vehicles (radius of 10 m). In order to prevent it being mistakenly driven in, mark fuel cell vehicle with a clearly visible sign or something similar.
• More information can be found in the corresponding repair and maintenance instructions.

Beginning work 

• Before repair work on the fuel cell system, carry out the following activities: 
  1. Close manual shutoff valves of fuel tanks.
  2. Drain pressure in fuel cell system. The fuel tanks can remain under pressure because the manual valves are closed off.
• Before removal of the fuel cell, carry out the following activities: 
  1. Drain pressure in fuel cell system.
  2. Perform flushing of fuel cell stack.
  3. Attach corresponding event logs onto fuel cell vehicle so that they are clearly visible and will not fall off. The respective event logs are listed in the corresponding repair and maintenance instructions.
• Before removal of one or both fuel tanks, carry out the following activities: 
  1. Empty fuel system.
  2. Inert fuel tank.
  3. Attach corresponding event logs onto fuel cell vehicle or fuel tank so that they are clearly visible and will not fall off. The respective event logs are listed in the corresponding repair and maintenance instructions.
• Thoroughly clean the working area on fuel cell vehicle, the tools and the workplace.
• If necessary, prepare specific tool for fuel cell system and auxiliary devices.
• Lay out lint-free cleaning cloths.

Work procedure 

• Thoroughly clean connecting points before opening.
• Close off connecting point immediately using suitable stop plugs and protective hoods.
• Only remove stop plugs and protective hoods immediately before installing parts.
• Immediately close off container for repair materials.
• Only use specific tool, specific auxiliary devices and permitted commercially available tools for operations on the fuel cell system.

End of job 

• After repairs on the fuel cell system, note the following:
  1. Place specified status listing in vehicle in clearly visible location and store in archive. The respective event logs are listed in the corresponding repair and maintenance instructions.
  2. After removal of one or both fuel tanks or the fuel cell: Attach an information sheet regarding condition (pressure/medium) so that it is clearly visible and will not fall off. The respective event logs are listed in the corresponding repair and maintenance instructions.
• Close off removed parts using suitable plugs.