Code result
P26D1
Engine Coolant Pump Control Module System Voltage High
Moderate severity
What it means
The smart coolant pump module reports the system voltage above operating range. Pump output is reduced or disabled to protect the 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
Alternator regulator failed to limit output
highOne of the most commonly reported causes for this code — check this first.
Load dump transient after disconnecting a heavy load
lowLess common, but worth ruling out after the more likely causes.
Related help
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