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 » U0659

Code U0659

Symptoms

• Check Engine Light is on

• Vehicle may not start

• Certain electronic features may not work

Common Causes

• Faulty control module

• Damaged wiring or connectors

• Software issues in the control module

Glossary

OBD-II: On-Board Diagnostics, a system that monitors vehicle performance.

Control Module: A computer within the vehicle that manages various functions.

Related Codes

• U0100

• U0140

Laymans terms

Your car's computer is having trouble talking to one of the parts. It's like when your phone can't connect to the internet.

Explanation

The vehicle's control module is unable to communicate with a specific component.

Technical description

OBD-II Code U0659 indicates a communication error between the vehicle's control module and the device it is trying to communicate with. This is typically due to a loss of communication with the 'A' circuit.

Diagnosis steps

• Use an OBD-II scanner to confirm the code

• Inspect wiring and connectors for damage

• Test the control module for proper operation

Repair procedures

• Repair or replace damaged wiring/connectors

• Reprogram or replace the control module

• Clear the code and test drive the vehicle

Tools required

• OBD-II scanner

• Multimeter

• Screwdrivers and basic hand tools

Estimated repair cost

$100 - $1000

Difficulty level

Moderate

Commonly affected vehicles

• Ford F-150

• Chevrolet Silverado

• Toyota Camry

Preventive measures

• Regularly check and maintain vehicle wiring

• Ensure software updates are applied

• Avoid exposure to extreme temperatures

Error code type

Communication Error

User experience recommendations

• Have a professional diagnose the issue

• Avoid driving the vehicle if it exhibits severe symptoms

Warranty information

Check with your vehicle manufacturer for warranty coverage on control modules.

Historical data

U0659 has been associated with communication issues in modern vehicles as they rely heavily on electronic systems.

Urgency level

Moderate – It's important to address this issue soon to avoid further complications.

Legal and safety notice

Ignoring communication errors can lead to vehicle malfunctions, which may compromise safety.

Testing conditions

• Vehicle must be in a safe, stationary position

• Ensure all electronic systems are powered on

Component location

The control module is typically located under the dashboard or in the engine compartment.

FAQs

Q: Can I drive with a U0659 code?
A: It's best to have the issue checked by a professional as soon as possible to prevent further problems.

Q: Will clearing the code fix the problem?
A: Clearing the code may temporarily turn off the warning light, but it won't fix the underlying issue.

Last updated: Oct 29, 2025 • Source: internal database

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