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 » P1505

Code P1505

Symptoms

• Inaccurate speedometer readings

• Check engine light illuminated

• Erratic transmission shifting

Common Causes

• Faulty vehicle speed sensor

• Damaged wiring or connections

• Faulty ECM

Glossary

ECM: Engine Control Module

OBD-II: On-Board Diagnostics, Second Generation

Related Codes

• P0500

• P0501

Official description

Vehicle Speed Implausible

Laymans terms

The car's computer is confused because the speed it's reading doesn't make sense.

Explanation

This code indicates that the vehicle's speed sensor is reporting a speed that doesn't match the expected values based on other data.

Technical description

The P1505 code is triggered when the Engine Control Module (ECM) receives a signal from the vehicle speed sensor that is not plausible when compared with other inputs such as engine RPM and gear position. This discrepancy may indicate a fault in the sensor, wiring, or related components.

Diagnosis steps

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

• Inspect the vehicle speed sensor and wiring for damage.

• Test the sensor output with a multimeter.

Repair procedures

• Replace the faulty vehicle speed sensor.

• Repair or replace damaged wiring or connectors.

• Reprogram or replace the ECM if necessary.

Tools required

• OBD-II scanner

• Multimeter

• Basic hand tools

Estimated repair cost

$100 - $300

Difficulty level

Moderate

Commonly affected vehicles

• Ford Focus

• Honda Accord

• Toyota Camry

Preventive measures

• Regular maintenance checks

• Ensure wiring is intact and protected

• Avoid harsh driving conditions

Error code type

Sensor Issue

User experience recommendations

• Drive cautiously until the issue is resolved.

• Avoid relying on the speedometer for accurate speed readings.

Warranty information

Check if your vehicle's powertrain warranty covers sensor replacements.

Historical data

This code has been common in vehicles with aging speed sensors or those exposed to harsh environments.

Urgency level

Moderate – It affects drivability but is not an immediate safety concern.

Legal and safety notice

Driving with an inaccurate speedometer may lead to speeding violations.

Testing conditions

• Vehicle in motion

• Engine running

Component location

The vehicle speed sensor is typically located on the transmission.

FAQs

Q: Can I drive with a P1505 code?
A: Yes, but it may affect speedometer accuracy and transmission performance.

Q: Will a P1505 code cause my car to fail emissions testing?
A: Not directly, but it may cause issues if related codes are present.

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

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