What is an OBD2 code?

An OBD2 (On-Board Diagnostics) code is a diagnostic trouble code (DTC) generated by your vehicle's computer system when it detects a problem. These codes help identify specific issues with your vehicle's engine, transmission, emissions, or other systems.

How do I read OBD2 codes?

To read OBD2 codes, you'll need an OBD2 scanner. Plug it into your vehicle's OBD2 port (usually located under the dashboard), turn your key to the 'ON' position, and follow your scanner's instructions to retrieve the codes. Each code starts with a letter (P, B, C, or U) followed by four numbers.

What do the different types of OBD2 codes mean?

OBD2 codes are categorized by their first letter: P (Powertrain) for engine and transmission issues, B (Body) for interior systems like airbags, C (Chassis) for mechanical systems like brakes, and U (Network) for computer and module communication problems.

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Home » OBD2 Codes » P0652

Code P0652

Symptoms

• Check Engine Light is on

• Poor engine performance

• Erratic sensor readings

Common Causes

• Faulty sensor

• Damaged wiring or connectors

• Defective PCM

Glossary

PCM: Powertrain Control Module

OBD-II: On-Board Diagnostics, Second Generation

Related Codes

• P0651

• P0653

Official description

Sensor Reference Voltage B Circuit Low

Laymans terms

Your car has a small problem with the electricity that helps some of its sensors work. It's like when a toy doesn't have enough battery power to work properly.

Explanation

The P0652 code indicates that the power supply to one or more sensors in the vehicle is lower than expected, which can affect the sensors' ability to function correctly.

Technical description

This code is triggered when the Powertrain Control Module (PCM) detects a low voltage condition in the sensor reference voltage circuit 'B'. This circuit provides a consistent voltage to various sensors, and a drop in this voltage can lead to incorrect sensor readings.

Diagnosis steps

• Use an OBD-II scanner to confirm the code.

• Inspect wiring and connectors for damage.

• Check the voltage supply to the sensors.

Repair procedures

• Repair or replace damaged wiring.

• Replace faulty sensor.

• Replace or reprogram PCM if necessary.

Tools required

• OBD-II scanner

• Multimeter

• Basic hand tools

Estimated repair cost

$100 - $500

Difficulty level

Moderate

Commonly affected vehicles

• Chevrolet Silverado

• Ford F-150

• Toyota Camry

Preventive measures

• Regularly inspect wiring for damage.

• Ensure connectors are secure.

• Perform routine maintenance checks.

Error code type

Sensor Issue

User experience recommendations

• Do not ignore the Check Engine Light.

• Have a professional diagnose the issue.

• Avoid driving the vehicle until the issue is resolved.

Warranty information

Check with your vehicle manufacturer for warranty coverage on electronic components.

Historical data

This code has been associated with wiring issues in vehicles manufactured in the early 2000s.

Urgency level

Moderate – This issue should be addressed soon to avoid further complications.

Legal and safety notice

Driving with this code may lead to reduced vehicle performance and safety issues.

Testing conditions

• Engine running

• Vehicle in park

Component location

The sensor reference voltage circuit is located within the vehicle's wiring harness, typically near the PCM or the affected sensors.

FAQs

Q: Can I drive with a P0652 code?
A: It's not recommended to drive with this code as it may affect vehicle performance and safety.

Q: How do I clear a P0652 code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is resolved first.

Last updated: Apr 16, 2026 • Source: internal database

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