: P0410 and P0418 on 2005 Bonneville GXP

03-02-11, 11:29 PM
Alright, I'm about ready to start pulling my hair out by the fistful over this issue. The other morning my wife took the GXP and ran an errand, then about an hour later I jumped in the car and noticed the SES light glaring at me from the dash. I recently activated OnStar for a three month trial, so as I was driving I had the advisor run a diagnostic on the car. The two codes that were present were P0410 (secondary air injection malfunction) and P0418 (secondary air injection pump relay circuit).

I've reset the codes a number of times and after the second start cycle the light comes right back. On the basis of the P0418 I went to the parts store and got a new relay, to no avail, the damned light still blazes away. I've checked all other fuses and relays for the AIR system, if it wasn't for the light I wouldn't even care if it wasn't working since the pump only runs on cold mornings for less than a minute.

Any thoughts, please someone save my sanity!

03-03-11, 11:11 AM
P0418 (secondary air injection pump relay circuit)
Might check the connectors and wiring, but those pumps (blowers) don't last forever. I just replaced one last year. Might be time to replace it. Might try to hot wire it first to be sure if it works or not first.