Mirror

Mirrors are safety-critical cab components for MAN and Mercedes trucks, buses and vans. Main mirrors, wide-angle mirrors, kerb mirrors and front mirrors reduce blind spots and provide the driver with visibility of adjacent traffic, vulnerable road users and loading or manoeuvring areas. On vehicles such as the MAN TGL, TGM, TGS, TGX, TG3 and TGE, and the Mercedes Atego, Actros, Arocs, Antos, Econic, Sprinter and Vito, mirror arms, mounting points, mirror glass, connector pin assignments and electrical functions vary considerably by version. Specific mirror systems also depend on bodywork and field-of-view configuration on MAN Lion’s City, Lion’s Coach and Neoplan coaches, as well as Mercedes Citaro, Intouro and Tourismo models.

A part must always be identified using the vehicle chassis number. Visual comparison or selection based solely on the model name is never sufficient. The same cab may be fitted with manually adjustable, electrically adjustable, heated, folding or camera-integrated mirror units, each with different wiring and mounting arrangements.

A complete mirror generally consists of a mirror housing, mirror arm or support bracket, mirror base, cover caps, mirror glass, adjustment motors, heating film, wiring harness and electrical connectors. Main mirrors usually feature flat or slightly curved glass for traffic behind the vehicle. Wide-angle mirrors are more convex and increase the field of vision, but make objects appear smaller. Kerb and front mirrors provide visibility of areas directly alongside or in front of the cab, which is particularly relevant for distribution work and urban traffic.

Mirror housings are generally made from impact-resistant plastic, while support arms may be made from aluminium alloys, steel or reinforced composite material. The fit of the mirror base on the door frame or cab corner must be free from stress; an incorrect model can come loose due to vibrations, cause wind noise or crack the plastic housing. Therefore, always check the side, arm geometry, length, mounting angle, connector type, number of pins and any heating or entry lighting function.

Common damage is caused by contact with posts, loading docks, branches or other vehicles. Signs include cracked housings, broken arms, play at the hinge point, loose mirror glass and a vibrating image at higher speeds. A mirror that folds in while driving often indicates wear in the spring mechanism, a deformed locking mechanism or an insufficiently secured mounting base. In the event of structural damage, replace the complete support structure; bonding or plastic welding rarely restores the original rigidity permanently.

If mirror heating is not working, first check the fuse, earth connection, connector corrosion and cable breakage in the arm. Use a multimeter to measure the supply voltage at the connector when the rear window or mirror heating is switched on. Then measure the resistance of the heating element in the glass; an open circuit indicates a faulty heated mirror glass. For electrical adjustment, check the power and earth signals, the switch in the door panel and the adjustment motors. A motor that can be heard running but does not move the glass often has damaged gears or a detached glass carrier.

On vehicles with mirror cameras or blind spot monitoring, the wiring harness must also be checked for kink damage. After replacement, diagnostic equipment may be required to clear fault codes or recalibrate a camera system.

Replace mirror glass immediately if it is cracked, has blind spots, has a deteriorating reflective coating or has faulty heating. Fit the glass without point loading on the clips, as local stress can later cause breakage. When replacing a complete unit, tighten the mounting bolts according to specification and route cables clear of sharp edges and moving parts. After installation, check the electrical functions, folding movement and field of vision from the normal seating position.

A correctly selected mirror with a proper fit reduces downtime and prevents recurring installation problems. Braem can assist with part identification based on the chassis number and offers a wide availability of cab components.