P1533 Subsidiary Throttle Valve Solenoid Circuit Malfunction

How to Diagnose and Solve P1533 Subsidiary Throttle Valve Solenoid Circuit Malfunction Issues


Are you a car enthusiast who loves to get your hands dirty? Or perhaps you’re a DIYer who enjoys the satisfaction of fixing things yourself? If so, you’re in the right place. Today, we’re going to delve into the world of car diagnostics, specifically focusing on the P1533 Subsidiary Throttle Valve Solenoid Circuit Malfunction.

Understanding the P1533 Code

First things first, let’s understand what the P1533 code means. This code is a generic powertrain code related to the throttle or pedal position sensor/switch. It indicates that the engine control module (ECM) has detected a malfunction in the subsidiary throttle valve solenoid circuit.

What is a Subsidiary Throttle Valve Solenoid?

The subsidiary throttle valve solenoid is a component of your car’s engine that helps control the amount of air entering the engine. It works in tandem with the throttle body to ensure the engine receives the right amount of air for optimal performance.

Common Symptoms of P1533 Code

When the P1533 code is triggered, you may notice some of the following symptoms:

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1. Check Engine Light is on
2. Poor engine performance
3. Reduced fuel efficiency
4. Difficulty starting the engine

Diagnosing the P1533 Code

Now that we know what the P1533 code is and its symptoms, let’s move on to diagnosing the issue.

Step 1: Use an OBD-II Scanner

The first step in diagnosing the P1533 code is to use an OBD-II scanner. This device can read the trouble codes stored in your car’s computer and provide valuable information about the issue.

Step 2: Inspect the Throttle Body

Next, inspect the throttle body for any signs of damage or wear. If you notice any issues, it may need to be replaced.

Step 3: Check the Wiring and Connectors

Check the wiring and connectors leading to the throttle body and the subsidiary throttle valve solenoid. Look for any signs of damage, corrosion, or loose connections.

Solving the P1533 Code

After diagnosing the issue, it’s time to solve it. Here’s how:

Step 1: Clean the Throttle Body

Sometimes, the issue can be resolved by simply cleaning the throttle body. Use a throttle body cleaner to remove any dirt or debris.

Step 2: Replace Damaged Components

If you found any damaged components during your inspection, replace them. This could include the throttle body, the subsidiary throttle valve solenoid, or any damaged wiring or connectors.

Step 3: Reset the Check Engine Light

After fixing the issue, use your OBD-II scanner to clear the P1533 code and reset the Check Engine Light.


Dealing with a P1533 Subsidiary Throttle Valve Solenoid Circuit Malfunction can be a bit daunting, but with the right knowledge and tools, you can diagnose and solve the issue yourself. Remember, it’s always important to address these issues promptly to prevent further damage to your vehicle.


1. What causes the P1533 code?
The P1533 code is usually caused by a malfunction in the subsidiary throttle valve solenoid circuit, which could be due to damaged components, wiring issues, or a dirty throttle body.

2. Can I drive my car with the P1533 code?
While it may be possible to drive with the P1533 code, it’s not recommended. The issue can affect your car’s performance and fuel efficiency, and could potentially cause further damage.

3. How can I prevent the P1533 code?
Regular maintenance and inspections can help prevent the P1533 code. Keep your throttle body clean and ensure all components are in good working condition.