So, I have a code 410 on my scanner. The AIR pump isnt comming on.
I've already changed the pump. Checked the fuse. Swapped the relay. Nothing.
My question is, what sensors tell the computer to turn the AIR pump on??
The car will be off the road for winter, so I'll have time to work on it.

 

The PCM turns on the AIR pump at startup to help heat the cats up faster. It appears to shut the pump down when the PCM goes into closed loop.

P0410 sets based on the PCM looking at the O2 sensor readings to verify that the pump is running and flowing air into the exhaust.

There is a passive test where it looks at the O2 sensors in open loop to verify the AIR is operating and producing an O2 level of 400mV or less. Then there is an active test where the PCM turns on the AIR pump in closed loop, and looks for the O2 to drop to less than 222mV, and/or the short term fuel corrections to change by 14 counts in response to the lean condition caused by the AIR flow.

 

I remember when it worked properly, that the AIR would come on at start-up, then turn off. It would also start up & turn off at various times during run.
So, it looks like I've eitehr got a faulty O2 sensor, or the PCM itself isnt working correctly.
You know, thinking of it, 1 of my cats, the one under the pass seat is going bad, think that that could be causing the O2 sensor to send a false reading back to the PCM??