Re: Hydraulic stop light switch

Posted by HH56 On 2016/4/12 15:25:35

On a 22nd series, there should be absolutely no connection between the taillight and brake circuits until each wire reaches the bulbs and lights their respective filaments. The filaments have a shared ground and is the only place the two circuits come together.

When the tail lights are on alone are the bulbs equally lit and are using the dimmer of the two filaments. Same with brake lights -- each bulb on the brighter filament and about the same light level.

I am wondering if possibly one side has the filaments reversed so the tail light is lighting the brighter filament. If that were the case, when brakes are applied it would light the dim filament and the additional light may be barely noticeable in comparison to the bright filament already being lit.

If the bulbs are the correct type and socket is not worn so they can be inserted improperly, the only other likely place for the switch to happen would be the 4 wire connectors near the left tail light. The overhead wires are plugged into the connectors and then each bulb is fed independently from that point. It is easy to get the filaments reversed there.