When carrying out welding or any other work involving the formation of sparks, be sure to disconnect the battery (positive and negative cables) and carefully insulate both terminals (-) and (+). When working near the battery, it must be removed.
Attention! When the battery is removed, the data from the electronic memory units is erased, in particular the radio receiver code. Without the code, the radio receiver can only be switched on by its manufacturer or a DAIMLER-BENZ service station. Read the notes in Section Checking the charging system.
Note: When welding galvanized sheets, toxic zinc oxide is formed. Therefore, it is necessary to ensure good ventilation of the workplace.
Increase the welding current by 10, maximum 30%.
Use solid copper electrodes with high thermal resistance (above +400°C).
Clean the electrodes more frequently and treat them to a contact surface diameter of 4 mm.
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Increase the pressure on the electrode.
Increase the welding time. The time is chosen correctly if the welding points are placed without spatter.
Air conditioner parts filled with refrigerant must not be welded or soldered with either soft or hard solder. This also applies to situations where there is a risk of heating of air conditioner elements when welding or soldering other structural elements.
Additionally
Do not open the air conditioner cooling circuit, as the refrigerant may cause frostbite if it comes into contact with the skin.
When applying paintwork in a drying oven, do not heat the car to a temperature above +80°C. Otherwise, the electronic devices of the car may be damaged. In addition, the pressure in the air conditioner increases, which can lead to the destruction of the system.
The protective coating of the car's underbody made of PVC is removed with a rotating steel brush or hot air at a temperature of up to +180°C using a spatula. Heating the PVC coating to a temperature above 180°C causes a chemical reaction and the formation of hydrochloric acid, which promotes active corrosion, and also produces harmful vapors.