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P2603 Severity
Identifying an OBD code is just the start of a complete diagnostic routine. Most trouble codes are caused by a sensor reporting a value that is out of range. Just replacing a sensor may not fix underlying issues. Be sure to understand the code, the part or system in your car that the code refers to, and the risks of delaying professional repair.
Proper diagnosis will save you time and money on unnecessary repairs.
Urgent codes indicate immediate action is necessary. These are urgent and significant malfunctions that can cause severe damage to the vehicle or harm the driver and passengers.
To Coolant Heat Storage (CHS) system allows the gas engine on a hybrid vehicle to warm up before the engine is actually started. This allows the gas engine to use less fuel when it is started. The CHS system uses a dedicated tank to store hot coolant. Before the engine is started, the electronically controlled engine water pump circulates this already hot coolant through the engine. If the engine computer (PCM) detects the electric pump is not operating properly, the PCM will set code P2603.
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OBD-II Code Powertrain Control Module (PCM) failure is defined as a Coolant Pump "A" Control Circuit High
To Coolant Heat Storage (CHS) system allows the gas engine on a hybrid vehicle to warm up before the engine is actually started. This allows the gas engine to use less fuel when it is started. The CHS system uses a dedicated tank to store hot coolant. Before the engine is started, the electronically controlled engine water pump circulates this already hot coolant through the engine. If the engine computer (PCM) detects the electric pump is not operating properly, the PCM will set code P2603.