OK, this was on my Audi, but guess it could apply to FFRRs ?

Audi gave warning on dash re brake light.

Checked all wiring and bulb, put back together. Worked. took for drive, warning came back.

Swapped bulbs from left to right. Worked. Took for drive warning light again on same side as before.

Thoroughly checked all wiring, tested bulb, improved (reduced) clearance on connectors in bulb holder. Put back together, tested - worked. Took for drive, warning light came back on.

This went on for a couple of weeks! I was almost at the point of hard wiring with solder the light to the car.

Had the light cluster out on the kitchen table, checked all the wiring everything connected, insert bulb, nothing.

Got bulb from the other side, worked! Hmmm.

Soldering iron out, added some solder to the connectors on the bottom of the non working bulb. Hey presto. Worked.

Although all connections worked and the bulb worked, something was going wrong down inside the connector when the bulb went in. By increased the amount of "solder" at the bttom of the bulb, it resolved the problem. .
Experience is the only genuine knowledge, but as time passes, I have forgotten more than I can remember
Volvo V70 P2 2006 2.4 Petrol 170bhp Estate SE
MG Midget Mk1 1962

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