Powertrain
generic / SAE
P26D5
Engine Coolant Pump Supply Voltage Circuit High
The dedicated supply voltage to the coolant pump module is above operating range. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number6 / D5
Possible causes
- Alternator regulator failed to limit output high
- Wiring shorted to a higher-voltage circuit low
- Connector pins corroded - high contact resistance low
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
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References
sae:J2012