Code result
U0023
Low Speed CAN Communication Bus
Moderate severity
What it means
CAN-High and CAN-Low on the low-speed comfort bus are shorted together. Both differential and single-wire modes fail; 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-H/CAN-L shorted together
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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