U0426
Invalid Data Received from Vehicle Immobiliser Control Module
What it means
The Vehicle Immobiliser Control Module is present on the data bus but the values it reports are implausible — out of range, frozen, or failing the checksum or rolling-count check. The receiving modules reject the data. Start authorisation may fail. Causes include a faulty sensor feeding the module, internal computation errors, a software or calibration mismatch after a repair, or bus interference corrupting the frames.
Is it safe to drive?
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
Immobiliser internal fault
mediumA plausible cause — test and verify before replacing parts.
CAN corruption causing checksum errors
mediumA plausible cause — test and verify before replacing parts.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
Related help
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