Refer to
AIR ,Gen Control Volts Lamp, Low Oil
.
Circuit Description
The Secondary Air Injection Reaction (AIR) system is controlled by the PCM. The system aids in the reduction of first and second cycle hydrocarbon emissions. During open-loop fuel control, the PCM energizes the AIR system. Air is injected into the exhaust stream for a specified amount of time. Heat generated from post-combustion oxidation helps the catalytic converter reach operating temperature sooner (referred to as converter light-off). The following conditions determine pump operation and run time:
| • | Start up ECT and IAT must be between 15°C - 110°C (59°F - 230°F) |
| • | If ECT sensor signal indicates an engine temperature above 70°C, total pump ON time is 40 seconds. |
| • | If ECT sensor signal indicates an engine temperature less than 70°C, total pump ON time is 100 seconds. |
The PCM monitors the AIR system in two stages (Passive and Active). The PCM initiates a two part Passive Test (stage 1) once each ignition cycle. Part one monitors the HO2S response when the PCM commands the air pump ON. If the HO2S remains proportionally lean (low HO2S signal) for a minimum of 5 seconds, part one passes and part two of the passive test is initiated. The second part of the passive test monitors the transition from open loop to closed loop fueling. When air injection to the exhaust is commanded OFF, the PCM monitors the HO2S response. If the HO2S signal switches from a lean to rich condition for a specific amount of time, part two passes. If part one and part two pass, further monitoring of the AIR system is discontinued. If any portion of the Passive Test fails, the PCM initiates the Active Test (stage 2). To run the Active Test, the AIR pump is commanded ON during warmed-up, closed loop operation. The PCM monitors the HO2S and long and short term fuel trim value response to air injection. If the HO2S signal remains proportionally lean (low HO2S signal) and the long and short term fuel trim values increase for a specific amount of time, the active test passes. If the HO2S and long and short term fuel trim values do not respond to air injection, the active test fails. If the PCM detects a consecutive number of active test failures, the appropriate DTC(s) will set. If a successful test occurs during the active test stage, a 'pass' indication results and the test will not run until the next ignition cycle. For further AIR system information, refer to Operation in Section C6
Conditions for Setting the DTC
| • | No active VSS, TP sensor, EVAP System, HO2S sensor, Misfire, IAT sensor, MAP sensor, IAC, Fuel Trim, Fuel Injector circuit, EGR Pintle, ECT sensor, CKP sensor or MAF sensor DTC(s) are set. |
| • | ECT sensor signal indicates temperatures between 75°C - 110°C (167°F - 230°F). |
| • | Engine run time greater than 3 seconds. |
| • | System voltage is greater than 9 volts. |
| • | Engine load less than 36%. |
| • | MAF less than 35 gm/s. |
| • | HO2S1 signal voltage remains above 300mV (0.3 volt) for 3 occurrences. |
Action Taken When the DTC Sets
| • | The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second key cycle in which the DTC sets. |
| • | The PCM will store conditions which were present when the DTC set as Freeze Frame and the Fail Records data. |
Conditions for Clearing the MIL/DTC
| • | The PCM will turn the MIL OFF on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present. |
| • | A history DTC P0410 will clear after 40 consecutive warm-up cycles have occurred without a fault. |
| • | DTC P0410 can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed. |
Diagnostic Aids
An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside the insulation. Check for the following items:
| • | Poor connection or damaged harness. Inspect the PCM harness and connectors for improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection, and damaged harness. |
| • | Poor hose/piping connections. Inspect the Secondary Air Injection system for disconnected or damaged hoses, crimped or broken piping, thread damage between the AIR piping and exhaust manifolds, and/or damaged clamps. |
| • | Remote air filter plugged or damaged. |
| • | Faulty HO2S heater or heater circuit. With the ignition ON, engine OFF, the HO2S voltage displayed on a scan tool should gradually drop to below 250 mV or rise to above 600 mV. If not, disconnect the HO2S and connect a test light between the HO2S ignition feed and heater ground circuits. If the test light does not light, repair the open ignition feed or sensor ground circuit as necessary (refer to Repair Procedures in Electrical Diagnosis, Section 8A-5). If the test light lights and the HO2S signal and low circuits are OK, replace the HO2S. |
Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused a fault to occur. This may assist in diagnosing the condition.
Important: Notice when replacing the AIR Bleed-off valve, inspect the left and right bank AIR Check Valves for a stuck open condition. Refer to Diagnostic Aids.
AIR Check Valve(s): When replacing the AIR Bleed-off valve assembly and/or the AIR Pump Assembly, test the left and right AIR check valves for a stuck open condition. Failure to inspect the check valves may result in premature failure of the replacement part. With the AIR feed hose disconnected from the AIR Pump Assembly, install a vacuum pump. Disconnect and plug the hose from the AIR Bleed-off valve assembly. Apply vacuum to the AIR feed hose. Vacuum should be holding steady. If vacuum is not holding steady, disconnect and plug the left bank AIR hose at the check valve. Apply vacuum to the AIR feed hose. If vacuum holds steady, replace the left bank check valve. If vacuum does not hold steady, replace the right bank check valve.
Notice: Inspect the left and right bank secondary air injection (AIR) Check Valves for a stuck open condition when replacing the AIR Bleed-off valve. Refer to diagnostic aids.
Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to OBD System Check | |||||||
2 | Is DTC P1642 also set? | -- | Go to DTC P1642 Chart | |||||||
3 |
Is the HO2S Bn1 Sen 1 voltage below the specified value? | 200mV (0.2V) | Refer to Diagnostic Aids | |||||||
4 |
Is the AIR Pump running? | -- | ||||||||
5 | Check for a blown AIR system fuse. Is the fuse blown? | -- | ||||||||
6 | Remove AIR system relay. Ignition ON, Engine OFF. Connect Test light to ground. Probe AIR system feed terminal in the relay connector. Is the test light ON? | -- | ||||||||
7 |
Is the test light ON? | -- | ||||||||
8 |
Is the AIR Pump running? | -- | ||||||||
9 |
Is the test light ON? | -- | ||||||||
10 |
Is the test light ON? | -- | ||||||||
11 |
Is the light ON? | -- | ||||||||
12 |
Is the light ON? | -- | ||||||||
13 |
Did the fuse blow? | -- | ||||||||
14 |
Is air injection present at the feed hose? | -- | ||||||||
15 |
Is the vacuum holding steady? | -- | ||||||||
16 |
Does the vacuum pump gauge indicate a vacuum at the specified value? | 0 in. | ||||||||
17 |
Was a problem found? | -- | Refer to Diagnostic Aids | |||||||
18 |
Is the test light ON? | -- | ||||||||
19 |
Was a problem found? | -- | ||||||||
20 | Locate and repair the short to voltage in the AIR system feed circuit (refer to Repair Procedures in Electrical Diagnosis, Section 8A-5). Is action complete? | -- | -- | |||||||
21 | Locate and repair open in the B+ feed to the AIR System Relay (refer to Repair Procedures in Electrical Diagnosis, Section 8A-5). Is action complete? | -- | -- | |||||||
22 | Locate and repair faulty splice/open in the B+ feed to the AIR pump (refer to Repair Procedures in Electrical Diagnosis, Section 8A-5). Is action complete? | -- | -- | |||||||
23 | Locate and repair faulty splice/open in the AIR System ground (refer to Repair Procedures in Electrical Diagnosis, Section 8A-5). Is action complete? | -- | -- | |||||||
24 | Locate and repair short to ground in the B+ feed to the AIR system relay (refer to Repair Procedures in Electrical Diagnosis, Section 8A-5). Is action complete? | -- | -- | |||||||
25 | Locate and repair short to ground in the AIR System feed harness (refer to Repair Procedures in Electrical Diagnosis, Section 8A-5). Is action complete? | -- | -- | |||||||
26 | Locate and repair faulty splice/open in the B+ feed to the Internal Shut-off valve (refer to Repair Procedures in Electrical Diagnosis, Section 8A-5). Is action complete? | -- | -- | |||||||
27 | Replace the AIR system relay Is action complete? | -- | -- | |||||||
28 | Replace the AIR Bleed-off valve. Is action complete? | -- | -- | |||||||
29 | Replace the AIR pump. Is action complete? | -- | -- | |||||||
30 | Locate and repair short to voltage in the AIR system feed circuit. Is action complete? | -- | -- | |||||||
31 |
Note test result; does scan tool indicate DTC P0410 Test Ran and Passed? | -- | Repair complete |
