P2600 indicates the engine computer has detected an open circuit in the electric auxiliary coolant pump control circuit. This pump is typically used for turbocharger cooling, cabin heater circulation, or after-run cooling, and the code means the computer cannot complete the electrical path to command the pump.
The pump motor itself is the most common failure, often seizing internally or burning out and creating an open circuit at the pump.
The control or power/signal wire can chafe, break, or corrode at connectors, causing an open circuit that the computer detects.
Connector pins at the pump are exposed to heat and moisture and can corrode, spread, or detach, interrupting the circuit.
A dedicated fuse or relay supplies the pump; if it opens, the control circuit may read as open depending on vehicle design.
Rarely, an internal driver failure in the computer can cause this code, but this should only be considered after the pump, wiring, and connectors are proven good.
Short trips may be fine, but if the pump supports turbocharger or after-run cooling, continued driving can cause heat soak damage. Have it diagnosed promptly.
No. P2600 refers to an electric auxiliary coolant pump, not the mechanically driven main water pump. The main pump is not controlled by this circuit.
Usually no. The pump and its wiring/connector are by far the most likely culprits. PCM replacement is a last resort and should only follow full circuit testing.
The code may clear after the repair and a drive cycle, but if wiring or connector faults remain it will return. Always verify the circuit before assuming the pump alone was the cause.