Code result
P201B
Intake Manifold Runner Control Actuator Supply Voltage Low
Moderate severity
What it means
The supply voltage feeding the IMRC actuator on bank 1 is below the lower limit — typically a fuse, relay, or harness fault on the supply rail.
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
Supply fuse blown
highOne of the most commonly reported causes for this code — check this first.
Open supply wire
mediumA plausible cause — test and verify before replacing parts.
Supply relay contacts pitted
mediumA plausible cause — test and verify before replacing parts.
Related help
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