On a right turn signal activation, the bulb failure indicator on the instrument cluster flashes in unison.

Both front and rear turn signal bulbs have been replaced with new bulbs and both are working. I have changed out the bulb failure sensor with no change.

What should I check next?

Did this problem start after you replaced some bulbs in the tail light clusters? Any chance you swapped positions of the bulb sockets? The double filament bulb socket is different than the single filament socket. And the right (white) double filament socket I'd different than the left (black). Putting the sockets in the wrong position will cause some weird results.

The bulbs are installed correctly and working. I'll check the ground condition.

Dear 94 945T,

Hope you're well. Clean the turn signal bulb-holdrs' contacts with the light cluster. Also inspect the ground wire connection with the cluster, and the ground wire's contact with the bodywork. Sometimes a film of corrosion a few molecules thick - too thin to be seen with an unaided eye or even a microscope - can disrupt power flow.

A few passes with fine steel wool will remove this corrosion. A thin coating of dielectric grease can be applied. The contacts will cut though this grease, which then keeps (moisture-laden) air away from the metal-to-metal contact, preventing new corrosion.

Hope this helps.

Yours faithfully,

Spook