Error Code 12

91 TSi AWD

Well my check engine light is on. I pulled the code and I believe it was 12. The code pulled as

S-S-S-L-L-S-S-S-L-L-S-S-S-L-L-S-S-S

S = Short
L = Long

If I am correct this means L - S - S or 12. Correct?

Volume air flow sensor = MAS?

Thanks

Mike