I have a 1993 Volvo 850 GLT and the check engine light is ON. My previous mechanic checked it 4 years ago when it came ON and determined that there is nothing wrong. He checked it again March of this year and nothing was wrong. Both times he reset it in the engine. Before retiring he showed me how to check the code and reset the light. It is the same code but I forgot how to reset the light in the Engine.