Celica Forums General Discussion Engine and Performance Codes from cel

everytime my car goes in, the dealer will clear my codes for me to shut off my cel. this time i asked him what they were so one of you smart celica gods can define them...
*171
*300
one is a missfire of some sort and the other is the maf, not sure why they are tripped but any help would be great.

*300 = IGNITER CIRCUIT MALFUNCTION NO. 1
* 171 = ?

i looked them up, but it could still have several different problems, has anyone else been through this, its kinda starting to piss me off. Can i just un plug the cel somehow? obviously if its gonna keep throwing the same codes im already gonna know about them, and i wont know if anything else goes wrong cause the stupid light is always on