Ford Escape: Automatic Transmission - Automatic Transmission – HF45 / Description and Operation - Transmission Description - System Operation and Component Description

System Diagram

E357528 *.sttxt { visibility: hidden; } *.stcallout { visibility: visible; } 1 ABS 2 BECM 3 DC/DC 4 GWM 5 PCM 6 ISC 7 Transmission 8 Motor/Generator Speed Sensors 9 Motor/Generator Coil Temp Sensors 10 TFT Sensor 11 Park Lock Actuator 12 Field Coils

Item	Description
1	ABS
2	BECM
3	DCDC
4	GWM
5	PCM
6	ISC (inverter system controller)
7	Transmission
8	Motor/Generator Speed Sensors
9	Motor/Generator Coil Temp Sensors
10	TFT Sensor
11	Park Lock Actuator
12	Field Coils

Network Message Chart

Broadcast Message	Originating Module	Message Purpose
ABS fault	ABS module	Supplies ABS system fault status.
Battery available status	BECM	Supplies HV system charge status.
Battery charge limit	BECM	How much charge the high voltage battery can accept.
Battery power charge/discharge	BECM	How much power the high voltage battery can provide.
Battery state of charge limit	BECM	Hazard lamp/malfunction indicator lamp illumination request.
Battery temperature (HV)	BECM	Determines the battery temperature for the actual state of charge.
Brake pedal movement	ABS module	Supplies brake status information for regenerative braking.
Engine RPM	PCM	Calculates engine torque.
PHEV / FHEV engine data	PCM	Calculates engine torque.
Regenerative braking mode	ABS module	Indicates when the brakes are applied to switch to regenerative braking mode.

System Operation

Component Description

Sensors and Actuators

Item	Description
1	TFT sensor
2	Park lock actuator

The TFT sensor is a thermistor located on the internal transmission harness. It sends a voltage signal to the ISC (inverter system controller). The voltage signal varies with TFT . The TFT sensor can not be serviced in vehicle, the transmission must be removed and disassembled.

The park lock actuator is an internally mounted actuator. The park lock actuator engages the park pawl with the park gear when commanded by the ISC. The park lock actuator cannot be serviced in vehicle, the transmission must be removed and disassembled. The PCM uses the park lock actuator signal for range selection, torque calculation and reverse lamp operation.

Park

Item	Description
1	Park lock actuator
2	Park pawl
3	Park rod

Power flow

In electric mode, torque flows from the electric motor to the transfer shaft and to the final drive ring gear. When the engine is off, the planetary carrier is held and the planetary ring gear is driven by the transfer shaft. This action causes the sun gear and the generator/starter to rotate. Under certain conditions, the SOBDMC will command the generator/starter to produce electricity for the electric motor and to charge the batteries.

Engine Starting Power flow

To start the engine, the final drive works as a holding element to the ring gear in the planetary assembly. The generator/starter turns the sun gear to start the engine.

Engine Charging Power flow

To charge the batteries, the final drive works as a holding element to the ring gear in the planetary assembly. The engine turns the carrier. This actions allows the generator/starter to produce current to charge the batteries and power the electric motor.

Regenerative Braking

When additional torque is needed to propel the vehicle, the generator/starter works as a holding element to the planetary sun gear. The flow of torque from the transfer shaft to the planetary ring gear is reversed and torque from the engine combines with the electric motor torque at the transfer shaft.