P06AB: Control Module Internal Temperature Sensor B Circuit

What it means

A fault has been detected in the control module internal temperature sensor B circuit. The code does not identify whether the cause is the sensor, wiring, or module.

At a glance

• Usually lights the check-engine light

How it works

The control module monitors an internal temperature sensor identified as sensor B through its own sensor circuit. This code sets when that circuit has an electrical fault, such as an open, short, poor connection, or failure of the internal sensor or module. It indicates a problem with the sensor-B circuit rather than confirming that the module itself is actually overheating.

Common causes

Most likely first.

1. Internal temperature sensor B or module fault
2. Open or short in sensor circuit
3. Poor connector contact

Symptoms

• Check-engine light may be on
• Module-related faults or reduced engine operation may occur

How to diagnose it

1. Record freeze-frame data and scan for other module temperature or communication faults to see whether the sensor-B circuit problem coincides with wider module issues.
2. Check live data for the module's internal temperature sensor B and look for a missing, fixed, or implausible reading.
3. Inspect accessible module connectors and harness sections for loose fit, corrosion, moisture, damaged wiring, or backed-out pins.
4. Using the manufacturer's wiring information, test the sensor-B circuit for an open or short and verify connector contact.
5. If the external connections pass, follow the manufacturer's procedure to determine whether the internal sensor B or the module has failed.

Common fixes

• Reconnect a loose module connector or repair a poor terminal contact.
• Repair an open or shorted section of accessible sensor-B wiring.
• Replace a damaged connector or restore a backed-out pin on the temperature-sensor circuit.
• Repair or replace the module if testing confirms its internal sensor-B circuit has failed.

Can I keep driving?

If the vehicle has reduced power, stalls, or shows other module warnings, stop driving and arrange diagnosis because the module may not be monitoring its temperature correctly. If it runs normally, limit driving until the sensor-B circuit fault is checked.