Code result
U0018
Medium Speed CAN Communication Bus (+) Low
Moderate severity
What it means
CAN-High on the medium-speed bus is shorted to ground. The differential pair cannot work, all body and comfort nodes drop offline at the same time.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
CAN-High shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
CAN terminating resistor (120 Ω) drifted out of spec
lowLess common, but worth ruling out after the more likely causes.
Related help
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