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2013 Toyota Highlander Hybrid – Cooling Fans Run With Ignition Off and C1378

Aug 16
1 min read

CUSTOMER CONCERN

The cooling fans continue running with the ignition off and DTC C1378 is stored.

CAUSE

Corrosion at the brake-control power-supply connector backfed voltage through the A/C No. 2 fuse circuit and kept the fan relays energized.

CORRECTION

Repair the corroded brake-control power-supply connector and terminals, clear DTC C1378, and verify the cooling fans shut off normally with the ignition off.

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2013 Toyota Highlander Hybrid – Cooling Fans Run With Ignition Off and C1378

CUSTOMER CONCERN

CAUSE

CORRECTION

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