Network, generic

U008F Vehicle Communication Bus G (-) Low

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U008F is the low-voltage fault on the (-) wire of Vehicle Communication Bus G, which on a CAN means CAN-Low touching ground. No public manufacturer document uses U008F. On a high-speed CAN this is one of the faults that let messages through: onsemi measured working transmission with distorted levels, and the node drew about 72 instead of 65 mA because a terminating resistor now drains to ground. NXP lists CAN-Low to ground among the shorts its TJA1043 reports although traffic continues, and warns that such tolerated faults raise current draw and spoil electromagnetic compatibility. A car can therefore run normally with U008F stored. With the battery disconnected, a (-) wire showing near zero ohms to chassis confirms it.

Likely causes

(-) wire chafed through to the body or a bracket
Moisture in a connector bridging the (-) pin to a ground pin
Damaged transceiver in one module pulling the line down

Symptoms

  • Often no noticeable effect, code found during a scan
  • Sporadic dropouts on Bus G

Repair estimate

DifficultyHardWorkshop job
Parts and labour€60–800
Time1–5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

bus g wiringcan low wire

Related codes

U0089U008EU0090U0091U0098

References: onsemi.com, nxp.com, law.cornell.edu.