AutoCodes – Generic – P00B6

P00B6 Code - Radiator Coolant Temperature/Engine Coolant Temperature Correlation

Quick Answer

The Radiator Coolant Temperature (RCT) sensor is a variable resistor that measures the temperature of the engine coolant in the radiator. Common causes include Faulty Radiator Coolant Temperature (RCT) Sensor, Radiator Coolant Temperature Sensor harness is open or shorted, Radiator Coolant Temperature Sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P00B6 indicates Radiator Coolant Temperature/Engine Coolant Temperature Correlation.
Common causes: Common causes include Faulty Radiator Coolant Temperature (RCT) Sensor, Radiator Coolant Temperature Sensor harness is open or shorted, Radiator Coolant Temperature Sensor circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 14,163

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Sep 30, 2022

Description
Possible Causes
How To Fix
Tech Notes ▶
Cost to Diagnose
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P00B6 Description

The Radiator Coolant Temperature (RCT) sensor is a variable resistor that measures the temperature of the engine coolant in the radiator. The Engine Control Module (ECM) supplies 5 volts to the RCT sensor signal circuit and supplies a ground to the low reference circuit. The purpose of this diagnostic is to determine if the input from the RCT sensor is skewed warmer than normal. The internal clock of the ECM will record the amount of time the engine is OFF. If the required engine OFF time is met at start-up, the ECM will compare the temperature difference between the actual measured RCT and Engine Coolant Temperature (ECT) sensors.
The Diagnostic Trouble Code (DTC) will be set when the ECM determines the absolute difference of temperature between the RCT start-up temperature and ECT start-up temperature is greater than 20°C (68°F).

OBDII Code P00B6 - Radiator Coolant Temperature/Engine Coolant Temperature Correlation - AutoCodes.com — P00B6 Code - Radiator Coolant Temperature/Engine Coolant Temperature Correlation

What does this mean?

What are the Possible Causes of the DTC P00B6?

Faulty Radiator Coolant Temperature (RCT) Sensor
Radiator Coolant Temperature Sensor harness is open or shorted
Radiator Coolant Temperature Sensor circuit poor electrical connection
Faulty Engine Coolant Temperature (ECT)
Faulty Engine Control Module (ECM)

How to Fix the DTC P00B6?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What does this mean?

Code Tech Notes

User Submitted Video

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P00B6 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P00B6 code?

Need more information on how to fix the P00B6 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P00B6 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P00B6 Buick — Radiator Coolant Temperature/Engine Coolant Temperature Correlation
P00B6 Cadillac — Radiator Coolant Temperature/Engine Coolant Temperature Correlation
P00B6 Chevrolet — Radiator Coolant Temperature/Engine Coolant Temperature Correlation
P00B6 GMC — Radiator Coolant Temperature/Engine Coolant Temperature Correlation

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.