On my ML350 got code 410 (secondary air injection) Which scared me because on mySL500 M119 I had to pull the heads for it.......
On the 06 ML I tested the air pump.Its good quiet good air flow.
Tested the changeover valve its good vacum and electrical
Tested both air valves at the heads they open and close and hold vacum.
Tested both heads with compressed air and cigar smoke so ports in heads are good, smoke and air come out both sides.(thank God!)
I know there is a relay that ops the system it opens the change over valve and turns on the pump. Does any one know where it is and how to test it? ,and can there be any other causes for this to malfunction??
Star finder does not show any pictures of the relay or its exact location in the eng compartment fuse relay box can I swap it with another one some relays look the same. Thanx in advance John............................................

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88 W124 3.0
96 R129 119eng
06 ML350
98 ML320 sold
02 CLK55 amg

Oh yes forgot to say when you start the car cold the air pump works fine comes on and pulls a good amount of air thru the air pump inlet,also when I get the code it comes up twice,the scanner says code 1 of 2 and they are both P0410 weird?

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88 W124 3.0
96 R129 119eng
06 ML350
98 ML320 sold
02 CLK55 amg

bump

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88 W124 3.0
96 R129 119eng
06 ML350
98 ML320 sold
02 CLK55 amg

turns out it was the air pump relay.It is one of the grey 4 prong relays that go in positions D,E & H in the eng compartment apparatus case. The air pump relay is position E, part #A 002 542 26 19.
I had swapped it out in the past to see if it was bad but it must have been a intermittent problem at the time. This time I swapped it with one of the eng circuit relays and the vehicle would not start. Bad relay for sure purchased a new one and code p0410 is gone now! Hope this helps someone else with trouble shooting a code P0410

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88 W124 3.0
96 R129 119eng
06 ML350
98 ML320 sold
02 CLK55 amg