U0622: Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 2

What it means

A control module has stopped receiving expected network messages from the exhaust gas temperature sensor on bank 2, sensor 2. The code indicates a communication fault; the effect depends on how the vehicle uses that sensor.

At a glance

• Usually lights the warning light of the system that lost communication
• Affects emissions; the car can fail an emissions test

How it works

Exhaust gas temperature sensor bank 2 sensor 2 reports exhaust heat at the second monitored position on engine bank 2. U0622 sets when a control module stops receiving that sensor's expected messages, so functions that rely on this specific downstream bank 2 reading lose it.

Common causes

Most likely first.

1. Bus wiring open or shorted
2. Module without power or ground
3. Module failed

Symptoms

• Warning light or message related to the affected system
• Exhaust temperature data may be unavailable

How to diagnose it

1. Scan all modules for related communication codes and record freeze-frame data to check whether bank 2 sensor 2 went offline with other faults.
2. Check live data for bank 2 sensor 2 and compare it with bank 2 sensor 1 and corresponding readings on bank 1.
3. Inspect the bank 2 sensor 2 connector and exhaust-area wiring for heat damage, chafing, corrosion, or loose pins.
4. Check the sensor module's power and ground against the manufacturer's wiring information.
5. Test the network circuit to bank 2 sensor 2 for opens and shorts using the manufacturer's procedure.
6. If wiring and supply pass, verify that this sensor module is not transmitting before replacing it.

Common fixes

• Repair heat-damaged or chafed wiring at bank 2 sensor 2.
• Clean or repair corroded or loose connector terminals.
• Restore module power or ground, or repair an open or short in its network wiring.
• Replace the bank 2 sensor 2 module if its supply and network circuit are sound but communication is absent.

Can I keep driving?

A short, gentle drive may be reasonable if the vehicle runs normally, but avoid sustained heavy load and monitor for emissions or aftertreatment warnings. Missing downstream temperature data can prevent systems that use it from controlling or checking exhaust treatment as intended.