I have a 1992 Volvo 940 gl and I took the stock radio out and put a new one in and hooked all the wires up properly but my brake lights won't work I have tried replacing bulbs checked all fuses and still nothing if I could get some help would be greatly appreciated

 

I would check the brake light switch.

 

I first check the big red "two story" relay--most likely the issue. The switch rarely goes bad.

 

KAEHLER 1362370 Volvo Bulb Failure Sensor Relay