Code result
U0027
Low Speed CAN Communication Bus (-) High
Moderate severity
What it means
CAN-Low on the low-speed bus is shorted to battery. Bus signaling is no longer possible; comfort modules drop offline.
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-Low shorted to battery
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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