Circuit Description

WARNING: This page is about a different car, the 2000 Pontiac Firebird, 2000 Chevrolet Corvette, and 2000 Chevrolet Camaro. However, it is still accessible from the selected car via links, so may be relevant.

Secondary Air Injection (AIR) system is used to lower tailpipe emissions during start up. PCM supplies ground to AIR pump relay, energizing pump.

PCM runs 2 tests using HO2S voltages to diagnose AIR system. Tests consist of:

Test I

PCM monitors HO2S voltages when AIR pump is enabled. If HO2S voltage drops to a predetermined range, PCM assumes that AIR pump is operational. If HO2S voltage increases to a predetermined range, PCM assumes that AIR pump is disabled. If HO2S voltages are out of range or inconclusive, diagnostic will proceed to next test.

Test II

During this test, PCM will activate AIR pump during "closed-loop" operation. When AIR is activated, PCM will monitor HO2S voltages and short term trim values for both banks of engine. If PCM determines that HO2S voltages for both banks does not respond as expected during tests, DTC P0410 will set. If only one sensor responded, PCM will set either a DTC P1415 or P1416 to indicate which bank AIR system is inoperative.

DTC will set when the following conditions are present:

TEST I

DTCs P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0171, P0172, P0174, P0175, P0300, P0401, P0404, P0405, P0412, P0418, P0441, P0443, P0506, P0507, P1120, P1220, P1221, P1404, P1441 or any HO2S DTCs not set.
Engine operating greater than 2 seconds.
TP sensor angle not moving greater than one percent.
Engine load less than 25 percent.
Engine airflow less than 30 gm/s.
Ignition voltage greater than 11.7 volts.
Air fuel ratio greater than 13:1.
ECT less than 228°F (109°C).
HO2S voltage drops to less than 400 mV.

TEST II

DTCs P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0171, P0172, P0174, P0175, P0300, P0401, P0404, P0405, P0412, P0418, P0441, P0443, P0506, P0507, P1120, P1220, P1221, P1404, P1441 or any HO2S DTCs not set.
Engine operating greater than 200 seconds.
Engine speed greater than 600 RPM.
Engine airflow less than 22 gm/s.
Ignition voltage greater than 11.7 volts.
ECT greater than 158°F (70°C).
IAT greater than 50°F (10°C).
Engine load less than 25 percent.
HO2S voltage does not drop to less than 222 mV within 1.5 seconds.
Short term fuel trim does not go above a predetermined amount.