If your W124 is experiencing a dash bulb warning light that comes on and off, it may be a hint that your headlamp connectors is not as tight as it should be anymore.
If the cause is not an actual faulty bulb, it is likely a loose connector.
This connector is one of the causes of a flickering bulb warning on your dashboard.
|W124 Euro Headlamp Connector|
After 20 or more years, the connectors might be slightly deformed and may not latch as well onto the male pins. A simple solution will be to add a layer of material on the non-conducting pin as shown below. This will introduce some friction and tightness onto the way the plug connects and will also increase the contact of the conducting pins. The material used was a 5mm diameter heat shrink.
|DIY increase contact and better latch for headlamp connector|
If this had solved your issues with the dash warning indicator, do share with other W124 owners!