my light came on and i have noting to read it with .. i did notice that under my hood along the firewall there is a row of pin connectors and there was a red light on .. i disconnected the battery to reset the light to see if it will come back on but just curious if anyone knows what that red light is

i read in a different post that you can buy a DMM from sears to read the engine codes .. but i have no idea what DMM is, and i dont know if i need anything additional to go along with the tool from sears

thanks in advance

1988 300se