U0690 code meaning
Lost Communication With EGR Temperature Sensor D
Network system Generic code U06xx codes Check engine light
What U0690 means
Sensor D is the last of the four EGR temperature slots, used only on systems with many measuring points, for example on both sides of a cooler in each of two EGR loops. U0690 says its digital messages have stopped reaching the controller. No manufacturer documents this code publicly, and none of the reviewed GM and Ford tables uses a D position at all. From 2013 on, CARB lists EGR temperature among the values the OBD system must report where fitted, and it requires EGR coolers to be checked for too little cooling; a missing reading can leave that check without data. CARB also asks for a separate code when a digital input falls silent. Analog faults are P04E5 to P04E9, and U068D to U068F cover the other three slots.
U0690 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 U0690
- Check engine light
- EGR cooler check incomplete
Common causes of U0690
- Most likelyWiring to sensor D damaged
- PossibleConnector loose 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 dVehicle bus wiring
What each part of U0690 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 90 | The exact fault in that area. |
What to do next
- Note U0690 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 U0690
What does U0690 mean?
U0690 means "Lost Communication With EGR Temperature Sensor D". Sensor D is the last of the four EGR temperature slots, used only on systems with many measuring points, for example on both sides of a cooler in each of two EGR loops. It is a generic code, so it means the same on every make.
Is it safe to drive with U0690?
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 U0690 fail an emissions test?
Yes, it can. U0690 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 U0690 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 U0690 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.