Engine-Codes - Generic - P0412

P0412 Code - Secondary Air Injection System Switching Valve 'A' Circuit Malfunction

- Code Popularity: 39,108 Views
- Repair Importance Level: 2/3
- Repair Difficulty Level: 2/3
Table of contents
ChatAC AutoCodes.com AI Chat

What are the Possible Causes of the DTC P0412?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Air Pump inoperative
  • Air bypass solenoid harness is open or shorted
  • Air bypass solenoid circuit poor electrical connection
⚠ Does your Car have Safety Recalls? → Check here

How to Fix the DTC P0412?

Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Search for P0412 Questions and Answers: Search here →

What is the Cost to Diagnose the Code?

Labor: 1.0

The cost to diagnose the P0412 code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.

When is the Code Detected?

The DTC P0412 is detected the the AIR vacuum control solenoid circuit not operating as desired by the PCM.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)
  • Engine hesitation

What Does the P0412 Code Mean?

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.

P0412 Code - Secondary Air Injection System Switching Valve 'A' Circuit Malfunction

Need more Information on the Code?

Need more information on how to fix the P0412 code? Get Access to Factory Service Manuals

Code P0412 Information for Specific Makes

  • P0412 Audi Secondary Air Injection System Switching Valve 'A' Circuit Malfunction
  • P0412 Buick Secondary Air Injection Solenoid Relay Control Circuit
  • P0412 Cadillac Secondary Air Injection Solenoid Relay Control Circuit
  • P0412 Chevrolet Secondary Air Injection Solenoid Relay Control Circuit
  • P0412 Chrysler Secondary Air Injection Switchover Solenoid Circuit
  • P0412 Dodge Secondary Air Injection Switchover Solenoid Circuit
  • P0412 Ford Secondary Air Injection System Switching Valve 'A' Circuit Malfunction
  • P0412 GMC Secondary Air Injection Solenoid Relay Control Circuit
  • P0412 Isuzu Secondary Air Injection Solenoid Control Circuit
  • P0412 Jeep Secondary Air Injection Switchover Solenoid Circuit
  • P0412 Lexus Secondary Air Injection System Switching Valve 'A' Circuit Malfunction
  • P0412 Mercedes-Benz Secondary Air Injection System Switching Valve 'A' Circuit Malfunction
  • P0412 Pontiac Secondary Air Injection Solenoid Relay Control Circuit
  • P0412 Saturn Secondary Air Injection Solenoid Relay Control Circuit
  • P0412 Toyota Secondary Air Injection System Switching Valve 'A' Circuit Malfunction
  • P0412 Volkswagen Secondary Air Injection System Switching Valve 'A' Circuit Malfunction

Need Help with the Code?

Get the P0412 code diagnosed by a professional: Find a repair shop in your area