P1CBD FIAT – Hydraulic Pump Overheating

P1CBD FIAT Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

P1CBD FIAT Possible Causes

Transmission Hydraulic System Fluid Level,Transmission Hydraulic System Fluid Leaks,Operator Driving Habits,Faulty Transmission Control Module (TCM)

P1CBD FIAT Description

This diagnostic checks for an over-temperature condition of the hydraulic Electro-Pump (EP). For example, a fluid leak or excessive gear shifting (excessive frequency of gear-shifts requested by the driver) may cause this condition. The Transmission Control Module (TCM) performs an over-temperature diagnosis based on the internal pump temperature (rotor and brushes) estimated by the pump thermal model. Specific recovery actions may be activated to prevent the pump from overheating. The diagnostic monitoring is based on three levels of severity and recovery by comparing the EP estimated brush temperature to three different thresholds: Temp 1 is a dynamic threshold and it is a function of pump duty cycle. Temp 2 is a dynamic threshold and it is a function of pump duty cycle and excessive gear shifting. Temp 3 is a fixed threshold and it is equal to the maximum calculated pump temperature.