Check engine light po412

PO412 - Secondary air injection system switching valve a circuit malfunction

here is what i found on p1416.



P1416 Chevrolet
P1416 Chevrolet - Secondary Air Injection System Bank 2
Possible causes
- Faulty Secondary Air Injection (AIR) pump
- Secondary Air Injection check valve bank 2
- Secondary Air Injection (AIR) pump electrical circuit fault
- Blocked Secondary Air Injection (AIR) system

When is the code detected?

The P1416 code is set when no O2 sensor voltage change is detected by the Engine Control Module (ECM).


Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)


P1416 Chevrolet Description
An Secondary Air Injection (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 Powertrain Control Module (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.

I'm going to post the description from engine-codes.com since it is a big paragraph. You will need a shop manual or else take it to a repair shop that has the equipment and book to check it out.

P0412 TOYOTA Description
An air pump is used on the vehicle to lower tail pipe emissions on start-up. The Powertrain Control Module (PCM) grounds the Air pump relay control circuit which energizes the Air pump. The PCM also grounds the Air combination valve vacuum control solenoid circuit, which energizes the Air vacuum control solenoid. Vacuum is then applied to both Air combination valve diaphragms which opens the shut off valves. The PCM enables both circuits simultaneously when Air system operations id desired. When the AIR system is active, then Air pump forces fresh air into the exhaust stream in order to accelerate catalyst operation. The AIR combination valves replace the conventional check valves. When the AIR system is inactive the shut off valves prevent air flow in either direction.
The DTC P0412 is detected the the AIR vacuum control solenoid circuit not operating as desired by the PCM.
Read more: http://engine-codes.com/p0412_toyota.html#ixzz2Y7OQTCbb

code po412 refers to secondary air injection(AIR) solenoid circuit malfunction Cause may include Wiring---AIR solenoid and ECM I would replace the AIR solenoid or check for power to it first.

PLEASE RATE THIS REPLY FOR ACCURACY

P0412 is related to the Secondary air injection system that inserts fresh air into the exhaust to promote a more complete fuel combustion.

Air pump is not working

16795/P0411/001041


if (window.showTocToggle) { var tocShowText = "show"; var tocHideText = "hide"; showTocToggle(); } 16795/P0411/001041 - Secondary Air Injection System: Incorrect Flow Detected Possible Symptoms

• Malfunction Indicator Light (MIL) ON

Possible Causes

• Fuel Pump Relay (J17) faulty
• Hoses/Pipes to/between Components faulty/clogged
• Secondary Air Injection Pump (V101) faulty
• Secondary Air Injection Pump Relay (J299) faulty
• Secondary Air Injection Solenoid Valve (N112) faulty

Possible Solutions

• Check Fuel Pump Relay (J17)
• Check Hoses/Pipes to/between Components
  • Check Secondary Air Injection Hoses/Pipes for Carbonization
• Check Secondary Air Injection Pump (V101)
• Check Secondary Air Injection Pump Relay (J299)
• Check Secondary Air Injection Solenoid Valve (N112)

not a big deal to have MIL light on. P0412 is secondary air injection valve switching A circuit.
Try this first. Disconnect battery for 1/2 hour. then reconnect and drive car for 10 miles so computer can relearn engine controls. may run rough during this time. See if that turns light off.

please rate me solved...thanks

DTC P0411/16795: SECONDARY AIR SYSTEM - INCORRECT FLOW DETECTED
Test Requirements
Ensure all fuses are okay, battery voltage is at least 11.5 volts, all electrical accessories are off, A/C is off.
Ensure engine is mechanically sound.
Test Procedure

NOTE
Secondary air system is activated by ECM and blows air into exhaust pipe
upstream of catalytic converter for 100 seconds during a cold start, 41-91°F (5-
33°C). Engine must be cold to perform following test procedure.

1. Ensure fuse and secondary fuse (secondary fuse is 40 amp and is located in fuse holder on top of battery)
are okay. Check hoses and components of Secondary Air Injection System, for damage, loose fit and
improper installation, check vacuum hoses for Secondary Air Injection System. Repair as necessary.
Erase DTC memory. Verify repair. If DTC does not reset, test is complete. Perform ECM relearn
procedure. See TEST DRIVE RELEARN PROCEDURE .
2. Remove engine cover. Disconnect pressure hose from Secondary Air Pump Motor (V101), by pressing
buttons on hose connector. See Fig. 33 . Using scan tool, check Secondary Air Pump Motor (V101) in
scan tool Output Diagnostic Test Mode (Secondary Air Pump Relay activation mode). See OUTPUT
DIAGNOSTIC TEST MODE .
3. Secondary Air Pump Motor (V101) should run in intervals and air should exit pump at hose connection.
If Secondary Air Pump Motor (V101) is okay, go to step 7 . If motor runs and no air exits secondary air
pump motor, replace faulty Secondary Air Pump Motor (V101). Erase DTC memory. Verify repair. Test
is complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE . If
secondary air pump motor does not run, go to next step.
4. Disconnect Secondary Air Pump Motor (V101) harness connector, install LED test light at secondary air
pump harness connector terminals. Turn ignition on. Using scan tool, activate Secondary Air Pump Motor
(V101) in scan tool Output Diagnostic Test Mode (Secondary Air Pump Relay activation mode). See
OUTPUT DIAGNOSTIC TEST MODE . LED test light at Secondary Air Pump Motor (V101) harness
connector should flash. If LED test light at Secondary Air Pump Motor (V101) harness connector does
not flash, go to next step. If LED test light at Secondary Air Pump Motor (V101) harness connector
flashes, replace faulty Secondary Air Pump Motor (V101). Erase DTC memory. Verify repair. Test is
complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE .
5. Using DVOM check resistance of Secondary Air Pump Motor (V101) wiring. See appropriate WIRING
DIAGRAM under ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS. Resistance should
be a maximum of 1.5 ohms for each reading. Check wiring for short circuit to one another in Secondary
Air Pump Motor (N101) harness connector. Repair as necessary. Erase DTC memory. Verify repair. Test
is complete. Perform ECM relearn procedure.
Secondary Air Pump Motor (N101) wiring is okay, go to next step.
6. Check Secondary Air Pump Relay (J299) and Secondary Air Pump Relay (J299) wiring. See DTC
P0418/16802: SECONDARY AIR PUMP RELAY (J299), MALFUNCTION . Repair or replace as
necessary. Erase DTC memory. Verify repair. Test is complete. Perform ECM relearn procedure. See
TEST DRIVE RELEARN PROCEDURE .
7. Disconnect vacuum hose from Secondary Air Injection Valve (N112) and disconnect pressure hose from
secondary air pump motor, press buttons on pressure hose connector to disconnect pressure hose. See Fig.
34 . Blow lightly into disconnected pressure hose, Combi-Valve should be closed. Connect hand vacuum
pump to disconnected vacuum hose and apply vacuum to Combi-Valve, Combi-Valve should open. If
Combi-Valve opens when vacuum is applied, Combi-Valve is okay. Go to next step. If Combi-Valve
does not open when vacuum is applied, replace faulty Combi-Valve. Erase DTC memory. Verify repair.
Test is complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE .
8. Check Secondary Air Injection Valve (N112). See DTC P0412/16796: SECONDARY AIR
INJECTION VALVE (N112), ELECTRICAL CIRCUIT MALFUNCTION . Repair as necessary.
Erase DTC memory. Verify repair. Test is complete. Perform ECM relearn procedure.
NOTE: Do not use compressed air to check Combi-Valve.
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