This fault code (DCS) is normally found on all vehicles with an inlet air cooler, also called the intercooler. In some cases (as with Peugeot and Citroën) the intercooler uses a combination of air and coolant to cool the inlet air. In this situation a coolant pump is used to pump the coolant through the system. Normally these are electronic liquid pumps. If, for some reason, the inlet temperature does not correspond with expected temperature of the system, then this fault code will appear.
Citroën Berlingo
Citroën C3 Picasso
Citroën DS3
Peugeot 207
Basically, every car that has been manufactured with the 1.4 VTI or 1.6 VTI engine.
An engine that receives air that is too cold or too warm will, of course, not run as it is supposed to. A loss in power is a logical result. The P023B can also cause a big increase in fuel consumption. Driving along with the fault can create annoying problems. As a result, we often see that the light for the engine management will be illuminated as soon as the fault code is triggered in a Peugeot or Citroën.
Just like most another faults, the P023B fault code can have several different causes. Online research of this fault code tells us that many different parts could be suspected. Commonly found faults are mechanical problems of the coolant pump, damaged cables to the coolant pump or problems with the pins or connectors. Another suspect is the Bosch MEV17.4 ECU that has been used with the 1.4 and 1.6 VTI engines. This last one is not strange; it regularly causes problems. Though, this fault code is often caused by a different problem.
Our experience is that the fault code P023B is caused by a faulty heater of the Positive Crankcase Ventilation valve. Verify the resistance of the heater using an Ohmmeter. The resistance of a proper working heating element should be around 10.9 Ohm. If there is a big difference then expect the fault to be in the heating of the PCV Valve. If this is the case then it could still be the ECU that is causing the problems. If so, then please contact us. Our product specialists will be able to help all car dealers and companies.
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