hey fellas i got a 1994 gmc 2500 hd with the 454 tbi in it the trouble light came on and it reads 12 first then code 36 which is iginition system circuit error I am not new to gm trucks but what the **** does that mean or what could cause it to send that code. it can't be any thing serious it starts to easy and idles perfectly. However i did notice right before the light came on it acted like the starter was going bad. Any ideas would be appreciated