Code result
U0321
Software Incompatibility With Suspension Control Module A
Moderate severity
What it means
A module reports a software version mismatch with suspension control module A — typically after replacing one of the modules without programming the new unit to match the rest of the network.
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
Module replaced without programming
highOne of the most commonly reported causes for this code — check this first.
Wrong part number for the vehicle
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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