U068D code meaning
Lost Communication With EGR Temperature Sensor A
Network system Generic code U06xx codes Check engine light
What U068D means
EGR temperature sensors show how hot the recirculated gas is, mostly behind the EGR cooler, so the controller can judge cooler efficiency and correct the gas density. U068D is the digital-link failure for sensor A. No public manufacturer source covers U068D. In the published tables sensor A is analog: GM's 2025 diesel table 25OBDG04A calls it the downstream EGR temperature sensor 2 and flags a resistance below 159 ohms as P040C, and Ford's 2023 diesel summary sets P040C under 0.69 V and P040B if the reading rises less than 10 °C after start. Neither has a SENT variant for A. CARB requires the EGR cooler to be checked and a separate code for any digital input that goes quiet. Analog faults are P040A to P040E; the A/B comparison is P040F.
U068D 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 U068D
- Check engine light
- EGR cooler monitoring not possible
Common causes of U068D
- Most likelyWiring to EGR temperature sensor A damaged near the cooler
- PossibleConnector oily, sooty or corroded
- PossibleSensor electronics failed
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
EGR temp sensor aVehicle bus wiring
What each part of U068D means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 8D | The exact fault in that area. |
What to do next
- Note U068D 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 U068D
What does U068D mean?
U068D means "Lost Communication With EGR Temperature Sensor A". EGR temperature sensors show how hot the recirculated gas is, mostly behind the EGR cooler, so the controller can judge cooler efficiency and correct the gas density. It is a generic code, so it means the same on every make.
Is it safe to drive with U068D?
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 U068D fail an emissions test?
Yes, it can. U068D 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 U068D 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 U068D clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.