Code result
P2603
Coolant Pump Control Circuit Low
Moderate severity
What it means
The electric coolant pump drive line reads below the lower threshold — typically a short to ground or a failed driver stage.
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
Drive line shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Driver stage failed
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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