Folks, I am still having the P0410 check engine. A quick overview = 2005 SRT6 coupe, runs great, 86k miles:



1) I started getting the P0410 code. RCM rebuilt by tighed1, new relays and horny mod. After I put in the rebuilt RCM, the 40A fuse blew as soon as I turned on the car from a cold start.
2) Replaced the 40A fuse on the RCM and with a voltmeter measured 14V or so on the connector going to the secondary air pump. So I figure my air pump needs replacement.
3) Replaced the air pump from K-Parts. Emission Smog Air Pump For Mercedes-Benz SLK32 AMG V6 3.2L S63 CL63 AMG V8 6.3L. Fit like a glove.
4) Now when I start the car cold I hear the air pump turn on for the first 30 seconds or so. I figure I fixed it, but wrong. After a day of driving, the P0410 comes back. I clear codes. Still comes back after a few days.
5) I replaced the blue air check valve from AutohausAB, (0021408460, Vacuum Check Valve). I clear codes. The air flow from the blue check valve seems fine. I follow the airline to the top of the blower and it also seems clear (not clogged).
6) After a few days of driving, I get the P0410.
7) Checked the ground connections on the SRT6 air pump location on the driver’s fender well. Disconnected and cleaned the battery terminals, then reconnected.
8) After a few days of driving, I get the P0410.
9) Replaced the Maybach EGR change over valve 0025401497, also cleaned the electrical connections. .
10) After a few days of driving, I get the P0410.
11) Removed the RCM and inspected the soldering connections just to make sure tighed1 didn’t forget anything. The connections look good and the relay contacts are good. I have pics. I also disconnected the large ground terminal connection to the frame from the negative battery terminal and cleaned the connection, then reconnected.
12) After a few days of driving, I get the P0410.


In summary = I replaced the RCM, Air Pump, Blue Check Valve, EGR valve. Plus checked and cleaned battery terminals and various ground hub terminals.



I have not spent much to try to fix this issue, maybe only $225. Most of my time has just been staring at the engine bay looking for ground points. Car still runs great, but one of these days I’m gonna need to pass emissions testing in NY state. I welcome additional advice from the forum.