P2BB7: Engine Coolant Temperature Sensor 6 Range/Performance

The ECM detects a range/performance fault on the engine coolant temperature sensor 6. Reading cannot be used reliably for control.

Symptoms

• Check engine light on
• Cooling fan runs constantly or not at all
• Cabin heater weak or excessively hot
• Possible long warm-up time or hard cold start

Most likely causes

• Sensor characteristic drifted
• Sensor mounting displaced
• Sensor element aged beyond calibration window

What to check, in order

Start with the simplest. You can tick off each step.

1. With the engine cold, check the coolant level; never do this when the system is hot
2. Compare the reading with other engine data while varying the engine speed.
3. Check the actual temperature in live data
4. Make sure the fan comes on when it should
5. Check the thermostat and connector
6. Measure the sensor and replace it if its readings do not make sense

Good to know

• Repair difficulty: easy
• It affects emissions.

What each character of P2BB7 means

• P: Powertrain: engine and transmission
• 2: Generic code: same on every make
• B: Subsystem depends on the code range
• B7: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2BB7?

Watch the temperature gauge. If it climbs or a warning appears, stop the car in a safe place and turn off the engine: overheating can cause serious damage.

What causes code P2BB7?

The most common causes are: sensor characteristic drifted; sensor mounting displaced; sensor element aged beyond calibration window.

Related codes

• P2B2CEngine Coolant Temperature Sensor 5 Circuit Range/Performance
• P2AFDEngine Coolant Temperature Sensor 4 Circuit Range/Performance

Sources

• github.com: dtc database
• en.wikipedia.org: Engine coolant temperature sensor

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.