P2432 – Secondary Air Injection System Air Flow/Pressure Sensor Circuit, Bank 1

How severe is this DTC?

The severity of this code can vary significantly from moderate to severe depending on the specific symptoms of the malfunction. Several symptoms of this fault code can make driving the vehicle extremely dangerous.

What are some of the symptoms of the code?

Symptoms of a P2432 fault code may include:

Engine may stall at idle
Engine may not start
Noisy secondary air injection system
Poor engine performance
Check engine light illuminated

What are some common causes of the code?

Causes of this P2432 code may include:

Faulty secondary air injection pump
Faulty one-way check valve
Faulty air control solenoid valve
Faulty air pressure sensor
Faulty or damaged wiring
Corroded, damaged, or loose connector
Faulty PCM

What are the troubleshooting steps for P2432?

The first step in troubleshooting any malfunction is to search for Technical Service Bulletins (TSBs) for the specific vehicle by year, model, and powertrain. In some circumstances, this can save you significant time in the long run by pointing you in the right direction.

Depending on the specific vehicle, this circuit may integrate several components, including the secondary air injection pump, the check valve, the pressure sensor, the air control valve, and the PCM. Perform a thorough visual inspection to check that the associated wiring does not have obvious defects such as scraping, rubbing, exposed wires, or burns. Then, check the connectors and connections for security, corrosion, and damaged pins. This process should include all wiring connectors and connections to all components, including the PCM. Consult the vehicle-specific technical data to verify the circuit configuration and confirm each component incorporated into the circuit, which may include a fuse or fusible link. The check valve must be tested to ensure airflow is in one direction only. Ice in the secondary air injection pump during extremely cold weather indicates a faulty one-way check valve allowing exhaust condensation to enter the pump.

Advanced Steps

Advanced steps become very vehicle-specific and require appropriate advanced equipment to function accurately. These procedures require a digital multimeter and the vehicle-specific technical references.

Voltage Checks

Reference voltage and acceptable ranges can vary depending on the specific vehicle and circuit configuration. The specific technical data will include troubleshooting charts and the appropriate sequence to follow to help you make an accurate diagnosis.

If this process identifies the absence of a power source or ground, continuity tests may be required to check the integrity of the wiring, connectors, and other components. Continuity tests should always be performed with the power disconnected from the circuit, and normal readings for wiring and connections should be 0 ohms of resistance. Resistance or lack of continuity is an indication of faulty wiring that is open, shorted, or corroded and must be repaired or replaced.

What are the common repairs for this code?

Replacement of the secondary air injection pump
Replacement of the faulty one-way check valve
Replacement of the air pressure sensor
Replacement of the air control solenoid valve
Cleaning corrosion from connectors
Repairing or replacing faulty wiring
PCM replacement

Common Mistake

Replacing the secondary air injection pump when a faulty one-way check valve or faulty wiring causes the PCM to set this code.
I hope the information in this article has helped point you in the right direction to correct the issue with the Bank 1 Sensor Circuit Flow/Pressure fault code for the secondary air injection circuit. This article is strictly informational, and the technical data and specific service bulletins for your vehicle should always take priority.

P2433 – Secondary Air Injection System Air Flow/Pressure Sensor Circuit, Bank 1

How severe is this DTC?

What are some of the symptoms of the code?

Symptoms of a P2433 fault code may include:

Engine may stall at idle
Engine may not start
Noisy secondary air injection system
Poor engine performance
Check engine light illuminated

What are some common causes of the code?

Causes of this P2433 code may include:

Faulty secondary air injection pump
Faulty one-way check valve
Faulty air control solenoid valve
Faulty air pressure sensor
Faulty or damaged wiring
Corroded, damaged, or loose connector
Faulty PCM

What are the troubleshooting steps for P2433?

The first step in troubleshooting any malfunction is to search for Technical Service Bulletins (TSBs) for the specific vehicle by year, model, and powertrain. In some circumstances, this can save you a lot of time in the long run by pointing you in the right direction.

Depending on the specific vehicle, this circuit may incorporate several components, including the secondary air injection pump, check valve, pressure sensor, air control valve, and PCM. Perform a thorough visual inspection to check that the associated wiring has no obvious defects such as scraping, rubbing, bare wires, or burns. Then, check the connectors and connections for security, corrosion, and damaged pins. This process should include all wiring connectors and connections to all components, including the PCM. Consult vehicle-specific technical data to verify the circuit configuration and confirm each component incorporated into the circuit, which may include a fuse or fusible link. The check valve must be tested to ensure airflow is in one direction only. Ice in the secondary air injection pump during extremely cold weather indicates a faulty one-way check valve allowing exhaust condensation to enter the pump.

Advanced Steps

Advanced steps become very vehicle-specific and require appropriate advanced equipment to perform accurately. These procedures require a digital multimeter and vehicle-specific technical references.

Voltage Checks

Reference voltage and acceptable ranges may vary depending on the specific vehicle and circuit configuration. Specific technical data will include troubleshooting charts and the proper sequence to follow to help you make an accurate diagnosis.

If this process identifies the absence of a power source or ground, continuity tests may be required to verify the integrity of the wiring, connectors, and other components. Continuity tests should always be performed with the power disconnected from the circuit, and normal readings for wiring and connections should be 0 ohms of resistance. Resistance or lack of continuity is an indication of faulty wiring that is open, shorted, or corroded and must be repaired or replaced.

What are the common repairs for this code?

Replacement of the secondary air injection pump
Replacement of the faulty one-way check valve
Replacement of the air pressure sensor
Replacement of the air control solenoid valve
Cleaning corrosion from connectors
Repairing or replacing faulty wiring
PCM replacement

Common Mistake

Replacing the secondary air injection pump when a faulty one-way check valve or faulty wiring causes the PCM to set this code.
I hope the information in this article has helped point you in the right direction to correct the issue with the Bank 1 Sensor Flow/Pressure Circuit fault code for the secondary air injection system. This article is strictly informational, and your vehicle’s specific technical data and service bulletins should always take priority.

P2434 Flow Sensor Circuit

🔧 Code P2434: Secondary Air Injection System Air Flow/Pressure Sensor Circuit (Bank 1) – Complete Guide

⚠️ Code Severity

The severity of P2434 ranges from moderate to critical depending on symptoms:

High risk if the engine stalls or fails to start.
Environmental impact: Increase in polluting emissions.
Possible damage to other components (e.g., catalytic converter) if ignored for a prolonged period.

📋 Common Symptoms

Engine stalling at idle or starting difficulties.
Abnormal noises coming from the secondary air injection system.
Decreased performance (weak acceleration, jerking).
Malfunction Indicator Lamp (MIL) illuminated.

🔍 Possible Causes

Faulty secondary air injection pump.
Blocked or broken check valve (common cause of frozen condensation in winter).
Faulty air solenoid valve or pressure sensor.
Damaged wiring (chafed wires, oxidized/loose connectors).
PCM failure (rare, check as a last resort).

🛠️ Diagnostic Steps

1. Basic Checks

Consult TSBs (Technical Service Bulletins) for manufacturer solutions.
Visual inspection:
Wiring: Look for cut, burned wires, or signs of corrosion.
Connectors: Check for cleanliness and secure fit (especially after the pump and check valve).
Check valve: Test air flow (must be unidirectional).

2. Advanced Tests (multimeter required)

Voltage check: Compare measured values to manufacturer data.
Circuit continuity: Measure resistance (≈ 0 Ω if wiring is healthy).
Pump test: Check its operation and power supply (12V).

🔧 Common Repairs

Replace the secondary air injection pump.
Change the check valve (moderate cost, frequent solution).
Clean or replace corroded connectors.
Repair wiring (solder or heat shrink tubing if necessary).
Update or replace the PCM (as a last resort).

❌ Common Mistake

Do not replace the pump immediately! A faulty check valve or bad wiring can trigger the same code.

📌 Important Notes

Use OEM parts to avoid incompatibilities.
Prioritize the vehicle’s technical data (repair manual or manufacturer software).
In cold climates: Check for ice in the pump (sign of a faulty check valve).

This article is informative. Always consult a professional for an accurate diagnosis, especially if the vehicle shows severe symptoms.

P2435 – Secondary Air Injection System Air Flow/Pressure Sensor Circuit, Bank 2

How severe is this DTC?

What are some of the symptoms of the code?

Symptoms of a P2435 fault code may include:

Engine may stall at idle
Engine may not start
Secondary air injection system making noise
Poor engine performance
Check engine light illuminated

What are some common causes of the code?

Causes of this P2435 code may include:

Faulty secondary air injection pump
Faulty one-way check valve
Faulty air control solenoid valve
Faulty air pressure sensor
Faulty or damaged wiring
Corroded, damaged, or loose connector
Faulty PCM

What are the troubleshooting steps for P2435?

The first step in troubleshooting any malfunction is to search for Technical Service Bulletins (TSBs) for the specific vehicle by year, model, and powertrain. In some circumstances, this can save you a lot of time in the long run by pointing you in the right direction.

Depending on the specific vehicle, this circuit may incorporate several components, including the secondary air injection pump, check valve, pressure sensor, air control valve, and PCM. Perform a thorough visual inspection to check that the associated wiring shows no obvious defects such as scraping, rubbing, bare wires, or burns. Then, check the connectors and connections for security, corrosion, and damaged pins. This process should include all wiring connectors and connections to all components, including the PCM. Consult vehicle-specific technical data to verify the circuit configuration and confirm each component incorporated into the circuit, which may include a fuse or fusible link. The check valve must be tested to ensure airflow is in one direction only. Ice in the secondary air injection pump during extremely cold weather indicates a faulty one-way check valve allowing exhaust condensation to enter the pump.

Advanced Steps

Advanced steps become very vehicle-specific and require appropriate advanced equipment to perform accurately. These procedures require a digital multimeter and vehicle-specific technical references.

Voltage Checks

Reference voltage and acceptable ranges can vary depending on the specific vehicle and circuit configuration. Specific technical data will include troubleshooting charts and the proper sequence to follow to help you make an accurate diagnosis.

If this process identifies a missing power source or ground, continuity tests may be required to verify the integrity of the wiring, connectors, and other components. Continuity tests should always be performed with the power disconnected from the circuit, and normal readings for wiring and connections should be 0 ohms of resistance. Resistance or lack of continuity is an indication of faulty wiring that is open, shorted, or corroded and must be repaired or replaced.

What are the common repairs for this code?

Replacement of the secondary air injection pump
Replacement of the faulty one-way check valve
Replacement of the air pressure sensor
Replacement of the air control solenoid valve
Cleaning corrosion from connectors
Repairing or replacing faulty wiring
Replacement of the PCM

Common Mistake

Replacing the secondary air injection pump when a faulty one-way check valve or faulty wiring is causing the PCM to set this code.
I hope the information in this article has helped point you in the right direction to correct the issue with the Bank 2 Sensor Flow/Pressure Circuit fault code for the secondary air injection system. This article is strictly informational, and the technical data and service bulletins specific to your vehicle should always take priority.

P2436 – Secondary Air Injection System Pressure / Flow Sensor Circuit Range / Performance, Bank 2

How severe is this DTC?

What are some of the symptoms of the code?

Symptoms of a P2436 fault code may include:

Engine may stall at idle
Engine may not start
Noisy secondary air injection system
Poor engine performance
Check engine light illuminated

What are some common causes of the code?

Causes of this P2436 code may include:

Faulty secondary air injection pump
Defective one-way check valve
Faulty air control solenoid valve
Defective air pressure sensor
Faulty or damaged wiring
Corroded, damaged, or loose connector
Faulty PCM

What are the troubleshooting steps for P2436?

The first step in troubleshooting any malfunction is to search for technical service bulletins (TSBs) for the specific vehicle by year, model, and powertrain. In some circumstances, this can save you significant time in the long run by pointing you in the right direction.

Depending on the specific vehicle, this circuit may incorporate several components, including the secondary air injection pump, check valve, pressure sensor, air control valve, and PCM. Perform a thorough visual inspection to check that the associated wiring has no obvious defects such as scraping, rubbing, bare wires, or burns. Then check connectors and connections for security, corrosion, and damaged pins. This process should include all wiring connectors and connections to all components, including the PCM. Consult vehicle-specific technical data to verify the circuit configuration and confirm each component incorporated into the circuit, which may include a fuse or fusible link. The check valve must be tested to ensure airflow is in one direction only. Ice in the secondary air injection pump during extremely cold weather indicates a faulty one-way check valve allowing exhaust condensation to enter the pump.

Advanced Steps

Advanced steps become very vehicle-specific and require appropriate advanced equipment to perform accurately. These procedures require a digital multimeter and vehicle-specific technical references.

Voltage Checks

If this process identifies the absence of a power source or ground, continuity tests may be required to verify the integrity of wiring, connectors, and other components. Continuity tests should always be performed with power disconnected from the circuit, and normal readings for wiring and connections should be 0 ohms resistance. Resistance or lack of continuity indicates faulty wiring that is open, shorted, or corroded and must be repaired or replaced.

What are the common repairs for this code?

Replacement of secondary air injection pump
Replacement of faulty one-way check valve
Replacement of air pressure sensor
Replacement of air control solenoid valve
Cleaning corrosion from connectors
Repairing or replacing faulty wiring
Flashing or replacing PCM

Common Mistake

Replacing the secondary air injection pump when a faulty one-way check valve or faulty wiring causes the PCM to set this code.
I hope the information in this article has helped point you in the right direction to correct the issue with the Bank 2 Sensor Flow/Pressure Circuit fault code for the secondary air injection system. This article is strictly informational, and your vehicle’s specific technical data and service bulletins should always take priority.

P2437 Secondary Air Injection System Air Flow/Pressure Sensor Circuit, Bank 2

How severe is this DTC?

What are some of the symptoms of the code?

Symptoms of a P2437 fault code may include:

The engine may stall at idle
The engine may not start
Noisy secondary air injection system
Poor engine performance
Check engine light illuminated

What are some common causes of the code?

Causes

of this P2437 code may include:

Faulty secondary air injection pump
Faulty one-way check valve
Faulty air control solenoid valve
Faulty air pressure sensor
Faulty or damaged wiring
Corroded, damaged, or loose connector
Faulty PCM

What are the troubleshooting steps for P2437?

The first step in troubleshooting any malfunction is to search for Technical Service Bulletins (TSBs) for the specific vehicle by year, model, and powertrain. In some circumstances, this can save you a lot of time in the long run by pointing you in the right direction.

Depending on the specific vehicle, this circuit may integrate several components, including the secondary air injection pump, the check valve, the pressure sensor, the air control valve, and the PCM. Perform a thorough visual inspection to check that the associated wiring has no obvious defects such as scraping, rubbing, bare wires, or burns. Then, check the connectors and connections for security, corrosion, and damaged pins. This process should include all wiring connectors and connections to all components, including the PCM. Consult vehicle-specific technical data to verify the circuit configuration and confirm each component incorporated into the circuit, which may include a fuse or fusible link. The check valve must be tested to ensure airflow is in one direction only. Ice in the secondary air injection pump during extremely cold weather indicates a faulty one-way check valve allowing exhaust condensation to enter the pump.

Advanced Steps

Advanced steps become very vehicle-specific and require appropriate advanced equipment to operate accurately. These procedures require a digital multimeter and vehicle-specific technical references.

Voltage Checks

What are the common repairs for this code?

Replacement of the secondary air injection pump
Replacement of the faulty one-way check valve
Replacement of the air pressure sensor
Replacement of the air control solenoid valve
Cleaning corrosion from connectors
Repairing or replacing faulty wiring
PCM replacement

Common Mistake

Replacing the secondary air injection pump when a faulty one-way check valve or faulty wiring causes the PCM to set this code.
I hope the information in this article has helped point you in the right direction to correct the issue with the Bank 2 Sensor Circuit Flow/Pressure fault code for the secondary air injection circuit. This article is strictly informational, and the technical data and service bulletins specific to your vehicle should always take priority.

P2438 – Secondary Air Injection System Air Flow/Pressure Sensor Secondary Circuit, Bank 2

How severe is this DTC?

What are some of the symptoms of the code?

Symptoms of a P2438 fault code may include:

Engine may stall at idle
Engine may not start
Noisy secondary air injection system
Poor engine performance
Check engine light illuminated

What are some common causes of the code?

Causes

of this P2438 code may include:

Faulty secondary air injection pump
Faulty one-way check valve
Faulty air control solenoid valve
Faulty air pressure sensor
Faulty or damaged wiring
Corroded, damaged, or loose connector
Faulty PCM

What are the troubleshooting steps for P2438?

Depending on the specific vehicle, this circuit may incorporate several components, including the secondary air injection pump, check valve, pressure sensor, air control valve, and PCM. Perform a thorough visual inspection to check that the associated wiring shows no obvious defects such as scraping, rubbing, bare wires, or burns. Then, check the connectors and connections for security, corrosion, and damaged pins. This process should include all wiring connectors and connections to all components, including the PCM. Consult vehicle-specific technical data to verify the circuit configuration and confirm each component incorporated into the circuit, which may include a fuse or fusible link. The check valve must be tested to ensure airflow is in one direction only. Ice in the secondary air injection pump during extremely cold weather indicates a faulty one-way check valve allowing exhaust condensation to enter the pump.

Advanced Steps

Advanced steps become very vehicle-specific and require appropriate advanced equipment to perform accurately. These procedures require a digital multimeter and vehicle-specific technical references.

Voltage Checks

If this process identifies a missing power source or ground, continuity tests may be required to verify the integrity of the wiring, connectors, and other components. Continuity tests should always be performed with the power disconnected from the circuit, and normal readings for wiring and connections should be 0 ohms of resistance. Resistance or lack of continuity indicates faulty wiring that is open, shorted, or corroded and must be repaired or replaced.

What are the common repairs for this code?

Replacement of the secondary air injection pump
Replacement of the faulty one-way check valve
Replacement of the air pressure sensor
Replacement of the air control solenoid valve
Cleaning corrosion from connectors
Repairing or replacing faulty wiring
PCM replacement

Common Mistake

Replacing the secondary air injection pump when a faulty one-way check valve or faulty wiring is causing the PCM to set this code.
I hope the information in this article has helped point you in the right direction to correct the issue with the Bank 2 Sensor Circuit Flow/Pressure fault code for the secondary air injection circuit. This article is strictly informational, and your vehicle’s specific technical data and service bulletins should always take priority.

P2439 Secondary Air Injection System Air Flow/Pressure Sensor Circuit, Bank 2 Intermittent/Erratic

How Severe Is This DTC?

What Are Some Symptoms of the Code?

Symptoms of a P2439 fault code may include:

Engine may stall at idle
Engine may not start
Noisy secondary air injection system
Poor engine performance
Check engine light illuminated

What Are Some Common Causes of the Code?

Causes of this P2439 code may include:

Faulty secondary air injection pump
Defective one-way check valve
Faulty air control solenoid valve
Defective air pressure sensor
Faulty or damaged wiring
Corroded, damaged, or loose connector
Faulty PCM

What Are the Troubleshooting Steps for P2439?

Advanced Steps

Advanced steps become very vehicle-specific and require appropriate advanced equipment to perform accurately. These procedures require a digital multimeter and vehicle-specific technical references.

Voltage Checks

If this process identifies a missing power source or ground, continuity tests may be required to verify the integrity of the wiring, connectors, and other components. Continuity tests should always be performed with the power disconnected from the circuit, and normal readings for wiring and connections should be 0 ohms resistance. Resistance or lack of continuity indicates faulty wiring that is open, shorted, or corroded and must be repaired or replaced.

What Are Common Repairs for This Code?

Replacement of the secondary air injection pump
Replacement of the faulty one-way check valve
Replacement of the air pressure sensor
Replacement of the air control solenoid valve
Cleaning corrosion from connectors
Repairing or replacing faulty wiring
Flashing or replacing the PCM

Common Mistake

Replacing the secondary air injection pump when a faulty one-way check valve or defective wiring causes the PCM to set this code.
I hope the information in this article has helped point you in the right direction to correct the issue with the Bank 2 Sensor Flow/Pressure Circuit fault code for the secondary air injection system. This article is strictly informational, and your vehicle’s specific technical data and service bulletins should always take priority.

P2440 – Secondary Air Injection System Switching Valve Stuck Open, Bank 1

P2440 Possible Causes

Faulty vacuum switching valve (VSV)
Vacuum switching valve (VSV) circuit open or shorted
Poor electrical connection in vacuum switching valve (VSV) circuit
Faulty pressure sensor
Faulty air switching valve

How to Fix Code P2440

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.

When is Code P2440 Detected?

If the engine control module (ECM) receives the pulsation signal from the sensor despite the ECM commanding the VSV to close the air switching valve, or if the ECM did not receive the sensor signal despite the ECM commanding the VSV to open the valve, the ECM interprets this as a fault in the secondary air injection system and the code is set.

P2440

Possible Symptoms

Illuminated engine light (or service engine soon warning light)

P2440 Meaning

To accelerate catalyst activation during engine warm-up, the air injection system pumps secondary air into the exhaust manifold by pressure. The secondary air is supplied by the air pump and is pumped to the exhaust manifold via the air switching valve. The opening and closing movement of the air switching valve is regulated by the vacuum switching valve (VSV). The air pump and air switching valve are monitored by the engine control module (ECM) and are used to detect malfunctions in this system. The ECM monitors the secondary air injection system and detects malfunctions using a pressure sensor located on the air switching valve.
The ECM observes the pressure in the secondary air passage using the pressure sensor located on the air switching valve in the secondary air injection system. The sensor detects exhaust pressure in the secondary air passage.

P2441 – Secondary Air Injection System Switching Valve Stuck, Bank 1

P2441 Possible Causes

Faulty Vacuum Switching Valve (VSV)
Vacuum Switching Valve (VSV) harness is open or shorted
Poor electrical connection in Vacuum Switching Valve (VSV) circuit
Faulty pressure sensor
Faulty air switching valve

How to Fix Code P2441

When is Code P2441 Detected?

If the Engine Control Module (ECM) receives the pulsation signal from the sensor despite the ECM commanding the VSV to close the air switching valve, or if the ECM did not receive the sensor signal despite the ECM commanding the VSV to open the valve, the ECM interprets this as a fault in the secondary air injection system and the code is set.

P2441

Symptoms

Possible

Illuminated engine light (or service engine soon warning light)

P2441 Meaning

To accelerate catalyst activation during engine warm-up, the air injection system pumps secondary air to the exhaust manifold by pressure. The secondary air is supplied by the air pump and is pumped to the exhaust manifold via the air switching valve. The opening and closing movement of the air switching valve is regulated by the Vacuum Switching Valve (VSV). The air pump and air switching valve are monitored by the Engine Control Module (ECM) and are used to detect malfunctions in this system. The ECM monitors the secondary air injection system and detects malfunctions using a pressure sensor located on the air switching valve.

The ECM observes the pressure in the secondary air passage using the pressure sensor located on the air switching valve in the secondary air injection system. The sensor detects exhaust pressure in the secondary air passage.