Code result
U0307
Software Incompatibility with Glow Plug Control Module
Moderate severity
What it means
The glow plug controller and the engine ECU run incompatible software versions. Cold-start preheating may be inhibited and the glow plug warning lamp can stay on.
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
Software flash mismatch after parts swap
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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