P0C47: Battery coolant-pump control line versus pump performance

P0C47 identifies an electrical fault on the battery coolant-pump control line in this GM table. The controller's hardware-support layer can report an open line, a short to voltage or a short to ground. The code title's word “open” does not limit the documented possibilities to one fault type.

A commanded pump state is part of the test

The pump-enable signal must be high and commanded PWM between 5 and 95 percent. System voltage must exceed 10.2 volts. A test with the pump disabled or with a command outside that window does not reproduce this control-line evaluation.

The fault is qualified through 40 failures in 50 samples at 100-millisecond intervals. Preserve the command, enable state and reported electrical status when interpreting an intermittent event.

Keep electrical and flow evidence separate

This diagnostic does not directly prove that coolant circulation is low. The adjacent P0C4A monitor evaluates pump performance through temperature behavior, which is a different kind of evidence. Replacing a pump because the scanner mentions it can miss an issue in the command path.

A qualified technician should identify the actual circuit and hardware using the vehicle-specific service documentation. The monitor table supplies no connector pinout, resistance specification or universal replacement decision. Investigation near the high-voltage battery cooling system requires the correct professional precautions, with the original electrical evidence retained for post-repair verification.

Source and applicability

15OBDG01 Hybrid Diagnostics, cited controller and monitor only. Historical calibration limits are not universal specifications; per-code vehicle, engine and hardware applicability must be verified.

GM source, physical page 561.