GTV fault code 1177 - any info?

[turbosei]

My friendly local mechanic read the ECU code from my GTV after the engine light came on, cleared it and it stayed out for a day then came back - same code, P1177. No loss of performance or noticeable change at all, but just an annoying light that keeps coming back every other day.

Can anyone tell me what this code means and what the normal remedy is?