481 fault code 99 grand prix se 3.1
 

for about a year now, I have been getting a 481 fault code (cooling fan 2 circuit problem) It was intermittant, now it is on constantly.Fans operate when air or defrost is on, but don't seem to run any other time. Temp gauge will redline, and still no fans. Checked fuses, quick wiring harness check, cleaned PCM terminals, changed sensor in manifold, still no help. Anybody have any ideas???????

RE: 481 fault code 99 grand prix se 3.1
 

it has to be something within the temp controller for the fans...i do not know of the remedy for this, but check with a parts store or stealership to see if they have a fan module for your car. it would come on with the defrost because the fans come on any time that the AC compressor is engaged, and it engages when the defrost is on.