I need help!! I couldn't get my inspection sticker cause of these codes, and i have no idea what they mean! My car is a 1999 trans am WS6 if that helps. If anybody can help me by telling me what they mean how i can fix it, that would help me out alot! the codes are:
P0410: Secondary Air Injection System Malfunction

P0412: Secondary Air Injection System switching valve A circuit malfunction

P0418: Secondary Air Injection System Relay "A" circuit malfunction

 

Here is a good thread for you that describes the air injection system.

https://ls1tech.com/ubb/cgi-bin/ulti...;f=23;t=000371

 

I am not sure but there might be a fuse in line to the evap system. Might want to check that, I would not think both your check valves would just go bad at least not at the same time

The air pump right have just quit, make sure the tub that goes to the check valves are not crushed/ripped.

The strut on my hood smashed the main hose going to the check valves and I tripped a secondary air injection code

“We don’t have inspection’s here; but I was thinking why not use an maft to set the base way lean. Just hope who ever is in inspecting the car does not know what that little box is. If you have a SES light just clear it before you drive up for inspection” <img border="0" alt="[Fluffy]" title="" src="graemlins/fluffy.gif" />

<small>[ August 07, 2002, 11:38 PM: Message edited by: dissonance ]</small>

 

This is what they mean for my '99 Z28:

P0410 - Circuit Description

An AIR pump is used on this vehicle to lower tail pipe emissions on start-up. The PCM supplies a ground to the AIR pump relay, which energizes the AIR pump. The PCM monitors the HO2S voltages to diagnose the AIR system.

During the AIR test the PCM activates the AIR pump during closed loop operation. When the AIR is activated, the PCM monitors the HO2S voltages and short term fuel trim values for both banks of the engine. If the AIR system is operating properly, the HO2S voltages should go low and the short term fuel trim should go high.

If the PCM determines that the HO2S voltages for BOTH banks did not respond as expected during the tests, DTC P0410 sets. If only one sensor responded, the PCM sets either a DTC P1415 or P1416 to indicate on which bank the AIR system is inoperative.

P0412 - Circuit Description

The PCM controls the relay by grounding the control circuit via an internal switch called a driver. The primary function of the driver is to supply the ground for the component being controlled. Each driver has a fault line which the PCM monitors. When the PCM commands a component ON, the voltage of the control circuit should be low (near 0 volts). When the PCM commands the control circuit to a component OFF, the voltage potential of the circuit should be high (near the battery voltage). If the fault detection circuit senses a voltage other than what is expected, the fault line status changes causing the DTC to set.

The relay controls the high current flow to the AIR injection pump integral bypass valve. This allows the PCM driver to only have to control the relatively low current used by the relay.

P0418 - Circuit Description

The PCM controls the relay by grounding the control circuit via an internal switch called a driver. The primary function of the driver is to supply the ground for the controlled component. Each driver has a fault line which the PCM monitors. When the PCM commands a component ON the voltage of the control circuit should be low (near 0 volts). When the PCM commands the control circuit to a component OFF, the voltage potential of the circuit should be high (near the battery voltage). If the fault detection circuit senses a voltage other than what the PCM is expects, the fault line status changes causing the DTC to set.

The relay controls the high current flow to the AIR injection pump. This allows the PCM driver to only have to control the relatively low current used by the relay.

***Also, in the troubleshooting section, it says the following:

If DTCs P0412 and P0418 are set at the same time, inspect the AIR pump fuse for an open. If the fuse is open repair the grounded circuit.

I'll email you the whole thing - too much info to post.

 

yeah - i think you're on to something as far as the hood causing a problem. According to a troubleshooting procedure, it stated that if all 3 of these codes were set, that means the AIR pump fuse is open - defective AIR relay, wiring shorted to ground, a bad AIR pump possibly, or AIR solenoid. There's a short somewhere in that circuit.

 

i just took my car to the dealership and they told me that the problem was that the air pump was closed and that i would have to replace it. They were going to charge me $700!!! to replace it so i said i would take it somewhere else. Im pretty sure that price was to high! I was just wondering if anybody here knew of anywhere i could buy an air pump or have someone do it for me in the Houston area, that would help me out a lot!! i need to get this done pretty quick since i need to get my inspection sticker already cause i don't want a ticket for that!! Thanks, all your responses will be appreciated!

 

Why don't you put a post in the classified forum and see if anyone has a pump they yanked off? Sure you could get one cheaper than GMs price.