Network · U codes · 1,230 codes
Network codes
Communication between control modules: lost communication, invalid data and bus faults.
Codes in this group
1,230
Generic SAE codes · OBDex
Rated urgent
43%
525 codes · our rating
DIY-friendly
13%
154 codes · per OBDex
Typical labor
$65–$375
Median hours × $125/hr · est.
01 —Subsystems
Network code groups
Lost communication
512 codesA module stopped hearing another module on the data bus. Usually power, ground, wiring or a failed module.
Invalid data & software
427 codesA module received implausible data, or two modules run incompatible software.
Bus & wiring
119 codesCAN/LIN bus circuit faults: shorts, opens and bus-off conditions.
Module power
170 codesModule supply voltage, ignition inputs, improper shutdown and module cooling.
Other network
2 codesNetwork codes outside the groups above.
02 —Start here
First U codes
- P00FFBody Control Module Requested MIL IlluminationOften: underlying BCM fault — read BCM codesModerate$40–$500 labor est.
- U0001High Speed CAN Communication BusOften: open circuit in CAN bus wiringUrgent$125–$1,000 labor est.
- U0002High Speed CAN Communication Bus PerformanceOften: corrosion or poor contact in CAN connectorsModerate$125–$750 labor est.
- U0003High Speed CAN Communication Bus (+) OpenOften: CAN-High wire broken or pin pushed backUrgent$125–$750 labor est.
- U0004High Speed CAN Communication Bus (+) LowOften: CAN-High shorted to groundUrgent$125–$625 labor est.
- U0005High Speed CAN Communication Bus (+) HighOften: CAN-High shorted to battery voltageUrgent$125–$750 labor est.
- U0006High Speed CAN Communication Bus (-) OpenOften: CAN-Low wire brokenUrgent$125–$750 labor est.
- U0007High Speed CAN Communication Bus (-) LowOften: CAN-Low shorted to groundUrgent$125–$625 labor est.
Code data: OBDex (CC0) · labor estimates at $125/hr, parts extra