U007D code meaning
Control Module Communication Bus K Off
What U007D means
U007D is one of the few late-alphabet bus-off codes with a public trace, all from GM's 2017 full-size trucks and SUVs (Silverado, Sierra, Tahoe, Suburban, Yukon, Escalade). There a serial data gateway module connects many CAN segments, and PIT5586 lists U007D next to U0073, U0078 and a long row of lost-communication codes. GM names two causes: bent, backed-out or loose terminals at gateway connectors X1 and X2, and a microcontroller fault that keeps the gateway powered but silent on every channel. For the latter GM's interim remedy is to pull the gateway's power fuse for a minute (F26DL on trucks, F28DL on SUVs) until a software update is installed, without replacing parts. Complaints range from dead gauges to no crank or start-then-stall.
U007D at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.3 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U007D
- Instrument cluster gauges dead or fluctuating
- No crank, no start or stall after starting
- Radio, climate controls or steering wheel buttons inoperative
- Numerous lost-communication codes in many modules
Common causes of U007D
- Most likelyBent, backed-out or loose terminals at the gateway connectors
- PossibleGateway microcontroller locks up and stops communicating
- Less likelyDamaged wiring on Bus K
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Gateway moduleBus k wiring
What each part of U007D means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 7D | The exact fault in that area. |
What to do next
- Note U007D 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 U007D
What does U007D mean?
U007D means "Control Module Communication Bus K Off". U007D is one of the few late-alphabet bus-off codes with a public trace, all from GM's 2017 full-size trucks and SUVs (Silverado, Sierra, Tahoe, Suburban, Yukon, Escalade). It is a generic code, so it means the same on every make.
Is it safe to drive with U007D?
Drive gently and only to a workshop. With U007D the car can go into limp mode (reduced power) to protect itself.
Will U007D fail an emissions test?
U007D is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U007D to fix?
Difficulty: medium. A typical repair takes 0.3 to 3 hours of work. This is a job for a workshop.
Will U007D clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.