Code result
P0600
Serial Communication Link Malfunction
Moderate severity
What it means
A general fault on a serial communication link - typically used by older single-wire diagnostic protocols (KWP2000, ISO 9141) before CAN became universal. ECU has lost or corrupted communication with another module.
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
Harness fault on bus line
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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