U068E code meaning
Lost Communication With EGR Temperature Sensor B
Network system Generic code U06xx codes Check engine light
What U068E means
GM documents this code in its 2025 diesel tables 25OBDG04A and 25OBDG04B, where sensor B is named EGR temperature sensor 1. Its circuit tests (P041C, P041D) are written for either a resistive probe or a digital thermocouple unit; the digital one counts as low below -72.8 °C. U068E covers the digital case: the check looks for SENT output switched off by an internal sensor fault, protocol errors or messages that are too old, and fails once 19 of 25 samples taken every 100 ms are bad while Run/Crank is active. It is Type A, so the MIL comes on in the first trip, and GM also logs a code for the input the sensor is wired to. Ford's 2023 diesels place sensor B behind the EGR cooler but read it as an analog signal. U068D, U068F and U0690 cover the other slots.
U068E 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 U068E
- Check engine light, on GM diesels in the first trip
- Second code for the controller input stored alongside
- EGR cooler efficiency not monitored
Common causes of U068E
- Most likelySENT signal, supply or ground wire to sensor B damaged
- PossibleInternal fault in the sensor that shuts off its output
- PossibleConnector corroded or contaminated by soot and oil
- Less likelyFault at the controller input the sensor uses
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
EGR temp sensor bVehicle bus wiring
What each part of U068E means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 8E | The exact fault in that area. |
What to do next
- Note U068E 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 U068E
What does U068E mean?
U068E means "Lost Communication With EGR Temperature Sensor B". GM documents this code in its 2025 diesel tables 25OBDG04A and 25OBDG04B, where sensor B is named EGR temperature sensor 1. It is a generic code, so it means the same on every make.
Is it safe to drive with U068E?
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 U068E fail an emissions test?
Yes, it can. U068E 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 U068E 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 U068E clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.