U0622 code meaning
Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 2
Network system Generic code U06xx codes Check engine light
What U0622 means
U0622 covers the second exhaust temperature measuring point on bank 2 when it is a digital sensor that transmits its value as SENT or CAN messages. The controller sets it once those messages stop or keep failing their checks, for instance after a broken signal wire, a lost 5 V supply or a fault inside the sensor module, an electronics box that on active sensors must tolerate up to 140 °C beneath the car. No manufacturer publicly documents U0622: GM's diesels with SENT temperature sensors have only one bank, and the Bentley V8 bulletins name only the sensors at position 1. CARB requires a dedicated code for a digital input that stops communicating, which is the role of this code. Judging by the documented neighbours, the harness routing near the exhaust is the first thing to inspect. Analog faults here are P2034 to P2036.
U0622 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0622
- Malfunction indicator lamp
- Exhaust temperature for bank 2 sensor 2 missing in live data
Common causes of U0622
- Most likelySensor wiring chafed or melted along the bank 2 exhaust
- Possible5 V supply or ground to the sensor interrupted
- PossibleHeat-damaged electronics module of the sensor
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Egt sensor bank 2 sensor 2Sensor wiring
What each part of U0622 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 22 | The exact fault in that area. |
What to do next
- Note U0622 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U0622
What does U0622 mean?
U0622 means "Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 2". U0622 covers the second exhaust temperature measuring point on bank 2 when it is a digital sensor that transmits its value as SENT or CAN messages. It is a generic code, so it means the same on every make.
Is it safe to drive with U0622?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will U0622 fail an emissions test?
Yes, it can. U0622 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is U0622 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will U0622 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.