The AIR system is used to accelerate the heating process of the catalytic converter
by introducing outside air into the exhaust manifold. The air pump operates on cold
engine starts when the catalytic converter works least efficient. The AIR system consists
of the air pipe/hoses, air pump, air pump relay, air pump solenoid, check valves,
shutoff valve, and PCM. The PCM controls the ground for the air pump relay coil, which
turns the air pump and air pump solenoid simultaneously ON or OFF. With the engine
running and the air pump commanded ON, manifold vacuum is allowed to pull up on the
shutoff valve. This allows pressurized air to flow past the check valve to the exhaust
manifold. The check valve is a one-way valve used to keep exhaust gases from entering
the air pump. During DTC P0410, the PCM will wait until certain engine parameters
have been met with the vehicle in a decel. The PCM will then command the air/fuel
ratio slightly rich and turn ON the air pump relay for a certain length of time.
When this occurs, the heated oxygen sensor 1 (HO2S-1) should indicate a lean
condition/low voltage. DTC P0410 sets when the PCM commands the AIR system
ON during a deceleration and the HO2S-1 signal does not indicate a lean condition.
DTC Parameters
DTC P0410 will set if the AIR system is commanded ON and the HO2S-1 voltage
is greater than 50 mV (not sufficiently indicating lean) when:
| • | The condition exists for three, 3 second tests. |
| • | The MAP is less than 30 kPa. |
| • | The engine run time is greater than 3 minutes and 20 seconds. |
| • | The ECT is between 5-115°C (41-239°F). |
| • | The IAT is greater than 0°C (32°F). |
| • | The TP angle change is less than 5 percent. |
| • | The STFT is between 119-133. |
| • | The ignition voltage is greater than 11.7 volts. |
| • | The engine speed is greater than 1150 RPM (auto), 1000 RPM
(manual). |
| • | Air flow is less than 127 grams/sec. |
| • | The commanded air/fuel ratio is fixed at 8 percent rich (13.5:1). |
| • | The loop status is closed. |
| • | No HO2S-1 DTCs have been set. |
DTC P0410 diagnostic runs once per ignition cycle once the above conditions
have been met.
DTC P0410 is a B DTC
Diagnostic Aids
Important: If the air pump relay circuit has faulted, the air pump relay circuit has faulted,
the air pump relay circuit is most likely the cause of the AIR system not working
properly and should be diagnosed first.
Check air pipes and hoses for leaks, cuts, or damage.
Check both check valves, one inline between the manifold vacuum supply and air
pump solenoid and the other inline between the shutoff valve and exhaust manifold.
They are both one-way valves. Air should only flow one way.
The scan tool can be used to turn the air pump relay ON and OFF. If the air
pump relay is turned ON, the air pump and air pump solenoid will turn ON simultaneously.
Air pump solenoid resistance is 24 - 45 ohms.
