Engine Light

I have a 1991 Dakota and the engine light is staying on. Just replaced the battery and also need new alternator soon. Whats the best way to get the engine light problem corrected? HELP

usually when the light is on, there's something wrong with the electronics, like a bad MAP sensor, TPS, etc. To access the codes, turn your ignition key on/off 3xs ending in the "ON" position. Your check engine light will flash. If it flashes twice then pauses and flashes another 4xs, that's a code 24, for example. The last code it will give you is 55 which is an "END OF CODES" message.