Trailblazer Code P0410 and Oxygen Sensors Replaced

Check Engine light Code P0410 A.I.R. System codes = P0410. Replaced O2 sensors a year ago. Question = Pulled the check valve. Applied 12V. Center "piston" cycles up and down but I don't see anything else move. Is that normal or should something else be moving? 2004 Chevy Trailblazer.

All I hear when I turn the ignition "on" is a whir for a couple of seconds. AIR? Checked fuses. All good. If this sound like the valve is good, next stop is checking the under hood and under car relays, right?

Have a subscription to Alldata but it does not talk about checking relays, only gives 58 steps to diagnostics, most requiring cycling things on and off via the code tool. Any help will be greatly appreciated. Starting vacation on Friday and would like to clear this up. There are TSB's on this. Any chance my Dealer would fix this at no charge?

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The bulletin you are referring to is just an update to the diagnostic chart. The original chart does not say that a faulty #1 o2 sensor can cause this, but it can. If no other problems are found, then replace #1 02 sensor. The other bulletins dont seem to apply. It talks about a redesigned pump intake hose and routing to prevent water from getting into the pump.

Most of the time the valve is the problem. But it sounds like it is working. Using a scanner to turn things on and off and watching 02 sensor readings is really the key to this diag. With the valve still on engine, and engine running, Another way is to jumper it as you have, Ensure the AIR outlet hose is removed from the AIR shut-off valve.

Connect a Fused Jumper Wire from battery positive voltage to either terminal of the AIR solenoid. Start and idle the engine.

Momentarily touch the other terminal of the AIR solenoid to a good ground with a jumper wire, 5 times for a duration of 2 seconds each. Is an audible exhaust sound heard at the inlet of the AIR shut-off valve, each time the circuit is connected to a ground, if yes, then the valve is working.

The pcm grounds the 'air sol' relay #55 in underhood block when parameters are met. That is why using a scanner to manipulate is important. This is all assuming the AIR pump works. Again, a scanner to manipulate these things is needed since there are many parameters that need to be met before pump will turn on.

There may also be a pcm re-program that addresses this problem, but the only way to tell is to have the dealer scanner on it and check. Since you are way over on mileage warranty, dealer most likely will not give assistance since there is bulletin, not recall. If mileage was close to 36k, they may have.

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