hey guys i have a 1990 volvo 240 i just did a temperature compensation board bypass which fixed my faulty temperature gauge but immediately after i installed the cluster the check engine light came on. so i went to advanced auto and they cant read the code because the car is so old. i was wondering if it has to do with what i just did to fix the temperature gauge. please help have to take my road test in a couple days and i don't know what they will say when they see the check engine light on.

 

Disconnect the battery for 20 mins or so; this will turn it off IF there is nothing else to trigger it.

I am not sure if your car has the diagnostic box on the driver's side by the strut tower to read the OBD1 codes. Look for it, it's a small black plastic box with probe usually tucked up under the cap.