What it means
Same as P242E on bank 2 sensor 3. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Bank 2 sensor 3 reports exhaust temperature to the control module for emissions control and protection of the DPF and catalyst. P246A sets when this sensor's signal becomes intermittent or erratic, such as from a vibration-sensitive connector or harness fault.
Common causes
Most likely first.
- Intermittent contact at connector
- Connector with intermittent contact under vibration
- Harness routed against vibrating component
Symptoms
- Check engine light on
- DPF or emissions warning light may come on
- Reduced power or limited regeneration may occur
- Increased fuel consumption
How to diagnose it
- Record freeze-frame data and review bank 2 sensor 3 live temperature for dropouts or sudden jumps and the conditions when they occur.
- Inspect the sensor connector for looseness, corrosion, moisture, or pins that may lose contact under vibration.
- Trace the bank 2 sensor 3 harness for chafing, heat damage, or routing against a vibrating component.
- Monitor live data while gently moving the connector and harness to reproduce an intermittent signal change.
- Check continuity and terminal contact through the sensor circuit while flexing the harness, using the manufacturer's wiring information.
- If the circuit remains stable, test bank 2 sensor 3 against the manufacturer's specification and replace it if its output is intermittent.
Common fixes
- Secure the bank 2 sensor 3 connector and repair loose or corroded terminals.
- Repair chafed or heat-damaged wiring and route it clear of vibrating or hot components.
- Replace a connector that cannot maintain reliable contact.
- Replace bank 2 sensor 3 if its signal remains intermittent with a sound harness.
Can I keep driving?
If the engine runs normally, drive gently and monitor for a DPF warning or power loss, but arrange diagnosis soon because the fault may recur with vibration or heat. Unreliable temperature feedback can interrupt regeneration or limit emissions-system protection.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.