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U0622 — Lost Communication Exhaust Gas Temperature Sensor Bank 2 Sensor 2

Generic OBD-II · all makesNetwork / communication

This code indicates the Powertrain Control Module (PCM) has lost digital communication with the Exhaust Gas Temperature (EGT) sensor located downstream of the catalytic converter on engine bank 2. The sensor transmits temperature data via a LIN or dedicated serial bus circuit, and the PCM can no longer establish valid contact with this specific device.

Symptoms

What causes it — most likely first

1. Failed EGT sensor (Bank 2 Sensor 2)

The internal electronics of the temperature probe commonly fail due to extreme exhaust heat and thermal cycling, causing a complete loss of LIN bus communication with the PCM.

2. Wiring harness damage

Opens, shorts to ground or voltage, or chafing in the LIN bus signal line, power feed, or ground circuit between the sensor and PCM connectors frequently occur due to proximity to hot exhaust components.

3. Connector corrosion or pin damage

Moisture intrusion, terminal corrosion, or backed-out pins at the sensor or inline harness connectors interrupt the digital signal path required for communication.

4. Exhaust system modifications or leaks

Aftermarket exhaust work may disturb or melt wiring, while upstream exhaust leaks can cause abnormal heat exposure that damages the sensor element or connector.

5. PCM internal fault

Rarely, a software glitch or failure of the internal LIN bus driver within the PCM prevents communication, but this should only be considered after verifying the sensor and all wiring are functional.

How it's diagnosed

  1. Locate Bank 2 Sensor 2 (post-catalytic converter on the bank opposite cylinder 1) and perform a thorough visual inspection of the sensor, harness, and connector for physical damage, corrosion, or evidence of exhaust leaks.
  2. Disconnect the sensor connector and verify proper battery voltage and ground are present at the harness side using a digital multimeter; also check that the LIN bus line rests at approximately battery voltage when the system is idle.
  3. Perform continuity and isolation tests on the LIN bus communication circuit between the sensor and PCM connectors to identify opens, shorts to power/ground, or high resistance.
  4. If wiring and powers/grounds are verified correct, replace the EGT sensor with a known-good unit and verify communication is restored via scan tool live data.
  5. Check for applicable Technical Service Bulletins (TSBs) regarding PCM software updates that may address false or intermittent communication faults before considering module replacement.
  6. Only after confirming the sensor, wiring, connectors, and grounds are functional, consider PCM reprogramming or replacement as a last resort.

Code facts & related codes

SystemNetwork / communication
StandardizationSAE generic — identical on every make

Frequently asked

Can I drive safely with code U0622?

Short-term driving is usually possible, but if the vehicle relies on EGT data for particulate filter regeneration or turbocharger over-temperature protection, continued operation may risk catalyst or turbo damage; repair should be scheduled promptly.

Do I need to replace the engine computer (PCM) for this code?

Almost never. This code specifically indicates a communication breakdown with one sensor; the fix is almost always the sensor itself, its wiring, or connectors. PCM failure is extremely rare for this specific fault and should not be replaced until all other causes are ruled out.

Where is Bank 2 Sensor 2 located?

Bank 2 refers to the cylinder bank opposite cylinder 1 (typically the passenger side on V-configured engines), and Sensor 2 is the EGT probe positioned downstream of the catalytic converter on that specific bank.

Will this code clear itself?

No. While intermittent connection issues might temporarily restore communication, the underlying fault will typically return until the failed sensor, damaged wiring, or poor connection is permanently repaired.