On the vehicles mentioned above, contact problems can cause the headlamps to fail.
The coating on the electrical pins (connection between light switch and cable connector) for the low beam can wear out over time. This results in significant contact problems (transition resistance/contact melting) and can cause the lighting to fail.
To eliminate this problem, connectors and cables should be checked and repaired/replaced as necessary. The switch must also be checked to ensure that it works correctly and is not damaged.
Important safety note