Severity High
P2135

Throttle/Pedal Position Sensor Correlation Fault

📅 Last reviewed: July 2026
What does the P2135 code mean?

The P2135 code indicates a correlation error between the throttle position sensor (TPS) and the accelerator pedal position sensor (APP). The engine control module (ECM) detects that the voltage signals from these two sensors do not match within a specified range, often due to a faulty sensor, wiring issues, or a defective throttle body. This can cause drivability problems and reduced engine performance.

High
Severity
$50-$150
Typical Cost
High
Frequency

1. Most Common Causes

2. Symptoms You Will Notice

3. Step-by-Step Diagnosis

1

Step 1: Use an OBD2 scanner to confirm the code and check for additional codes.

2

Step 2: Visually inspect wiring and connectors for damage, corrosion, or loose connections.

3

Step 3: Test throttle position sensor and accelerator pedal position sensor voltages with a multimeter and compare to manufacturer specs.

4

Step 4: If sensors are within spec, check for throttle body carbon buildup or mechanical binding.

5

Step 5: Replace faulty sensor or throttle body as needed and clear the code.

4. Frequently Asked Questions

Is it safe to drive with this code?

It is not recommended to drive with this code as it can cause sudden loss of throttle control or reduced power, leading to unsafe driving conditions.

How much does it cost to fix?

The cost typically ranges from $50 to $150 for DIY sensor replacement, or $200 to $500 if professional labor and throttle body replacement are needed.

5. Commonly Affected Makes

This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.

6. Related Codes

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