If compliance with regulations is verified by a general operating permit (ABE) for vehicle parts or a parts certificate, an acceptance certificate is required, which may form the basis for the correction of the registration certificate Part I (old vehicle registration document) and the registration certificate Part II (old vehicle registration document) by the registration authority. This does not apply to vehicle parts if the ABE does not stipulate an acceptance requirement.

Tip:
Before installation or conversion, an officially recognized expert for motor vehicle traffic or a test engineer from a monitoring organization should be consulted to determine whether the type approval is affected or whether the modification can be approved at all and thus whether a positive expert opinion can be issued for a new type approval.

Note:
Certain technical modifications must be reported to the registration authority without delay and, depending on the type of modification and the proof required, must first be inspected by the technical inspection authority or an approved inspection organization (TÜV, DEKRA, GTÜ, KÜS, GTS, FSP). This includes, for example

• Changes to the vehicle class or the vehicle and body type
• Change in cubic capacity, rated power, fuel type or energy source
• Increase in the maximum design speed
• Reduction of the maximum design speed if this is relevant to the driving license or registration
• Modification of the permissible axle loads, the total mass, the drawbar load or trailer load
• Increase in vehicle dimensions, except for passenger cars and motorcycles
• Changes to the number of seats or standing room in buses and coaches
• Changes to the exhaust or noise values, insofar as they affect vehicle tax or traffic bans
• Use of other wheel/tire combinations