Mercedes-Benz W201 instrument cluster and control lights not working
Why do the Mercedes-Benz W201 instrument cluster and heater control lights not work?
The most common cause is the instrument lighting dimmer, which can be dirty, oxidised or have loose solder joints. Other causes are a loose or oxidised wire behind the light switch and a blown fuse behind the instrument cluster. When the lights flicker as you move the wire, the fault is in the wire or connector.
How can a dimmer fault be fixed on the W201?
Remove the instrument cluster and check the dimmer from behind. Clean the contacts with contact spray and turn the control back and forth. If the solder joints are loose, they are resoldered. A dimmer fault can black out the dashboard lights even though the fuses are intact.
What wattage bulbs are used in the control lights on the W201?
A 0.4 W frosted bulb suits the lighting of the heater control knobs. Clear 1.2 W bulbs can melt the base of the knobs and blow the fuse behind the instrument cluster. It is best not to keep the instrument lights at full brightness, because they turn the plastic brown.