HEXA

TRANSMISSION

The transmission electrical connector is an

important part of the transmission operating

system. Any interference with the electrical

connection can cause the transmission to set

diagnostic trouble codes or affect proper

operation.

Internal Mode Switch (IMS):

The transmission manual shift shaft position,

given by the Internal Mode Switch (IMS), is a

sliding contact switch that connects to the manual

valve located inside the mechatronic. The four

inputs to the TCM from the position switch

assembly indicate which transmission gear range

(PRND) is selected.

Note:

This is for information only. Disassembly of this

component is not allowed.

Input & Output Speed Sensors:

The Input and Output Speed Sensor (ISS & OSS)

are hall-effect type sensors. They both connect to

the TEHCM through a wire harness and

connector. These signals are used to determine

line pressure, transmission shift patterns, torque

converter clutch (TCC) slip speed and gear ration

addition to the CAN bus data

Note:

This is for information only. Disassembly of this

component is not allowed.

Transmission Fluid Temperature (TFT) Sensor:

The Transmission Fluid Temperature (TFT)

sensor is located in TEHCM.

The TFT is a thermistor, which changes value

based on transmission oil temperature.

Shift Scheduling

The Controller Area Network (CAN) was created

in order to increase communication reliability,

rapidity, capacity and flexibility between the

electronic systems of the vehicle and to create a

database to avoid information transmission

failures.

Clutch-to-Clutch

transmission

technology

performs gear shifts by simultaneously applying

one clutch while releasing another. A precise

timing is required to ensure optimal shift quality.

Direct Pressure Control of Clutch to Clutch:

Two pressure commands are required to make a

shift, one to control the oncoming clutch, one to

control the off going clutch. A Variable Bleed

Solenoid (VBS) is used to directly generate each

pressure command which acts on a control valve

to regulate the pressure delivered to the clutch.

Shift valves can be used to multiplex the clutches

on which the regulator valves act and to give

failure mode protection.

Terminology:

Oncoming clutch:

The clutch being applied

during a shift. If two are to be applied, one is

selected as the Primary and one as the

Secondary.

Off going clutch:

The clutch being released

during the shift.

Common or Holding clutch:

This is the clutch

that remains applied during a shift.

Under lap:

When the Off going clutch is released

before the oncoming clutch has capacity. In power

on conditions this often known as Flare.

Overlap:

When the oncoming and Off going both

have capacity at the same time, also known as

Tie-Up.

Towing recommendation:

Vehicle recovery towing requirement, Vehicle to