Integrated Trailer Control Module
DESCRIPTION
| 1 - ITCM |
The Integrated Trailer Control Module (ITCM) is located behind the lower quarter trim panel at the base of the D-pillar on the passenger rear of the vehicle. The ITCM can be programmed for the type of trailer that is connected using the radio screen setup menu. Up to four trailer connection types can be stored in the ITCM for future reference when a trailer is reconnected at a later time. This data is latched during a key OFF when a trailer is connected in order to prevent having to reset the type of trailer during a key OFF event, such as a fuel stop.
Selectable trailer types are:
- Trailer
- Boat
- Car
- Cargo
- Dump
- Equipment
- Flat
- Livestock
- Horse
- Motorcycle
- Snowmobile
- Travel (Trailer)
- Utility
Vehicles equipped with the ITCM option feature a pinch-type switch called the Integrated Trailer Brake Switch (ITBS) in the steering column opening cover.
OPERATION
The ITCM controls and monitors the lighting as well as the electric brakes or the Electric Over Hydraulic (EOH) brakes for a trailer that is properly connected to the vehicle. The ITCM controls the brakes (electric or EOH) of a trailer in order to reduce the braking distance and for a better dynamic behavior of the vehicle and trailer braking system and includes data for Electronic Stability Program (ESP), Hill Start Assist (HSA), Active Cruise Control (ACC) and Forward Collision Warning (FCW) as well as trailer sway events.
The ITBM receives odometer data from the Instrument Panel Cluster (IPC) over the Controller Area Network - Chassis (CAN-C) data bus from which the ITBM calculates the mileage distance for the trailer that has been connected to the vehicle an accumulates across key cycles for as long as the trailer is connected to the vehicle. This calculation is then sent to the IPC over the CAN-C data bus to be used in displaying the trailer trip information to the driver or reset using the Electronic Vehicle Information Center (EVIC) switch for the trailer trip odometer.
The trailer trip odometer feature will only work with trailers that are equipped with electric or EOH brakes.
The ITCM outputs:
- Power to the trailer brake system
- Instrument Panel Cluster (IPC) display requests
- Trailer brake control output signal to the trailer based on the brake pressure in the master cylinder and also based on the type of trailer and gain input from the user via the ITBS
- Trailer connection status and information signal
- Chime requests
The ITCM monitors the Controller Area Network - Chassis (CAN-C) bus network for braking and lighting requests from the Body Control Module (BCM) as well as other inputs. The ITCM is responsible for its own logic, actuation and sensing.
ITCM HARDWIRED CONNECTIONS
- One 30 amp fused B(+) power supply circuit in the interior Power Distribution Center (PDC)
- Two 25 amp fused B(+) power supply circuits in the rear PDC
- One 10 amp fused RUN/START relay output in the rear PDC
- Trailer brake gain data
- Manual trailer brake input
- Trailer present test signal to ITBS
- Trailer present from ITBS
The ITCM makes certain that lighting functions are maintained synchronous with the vehicles lighting requests as read on the CAN-C bus. The ITCM then sends the appropriate output OFF or ON signal to the respective trailer lights. The ITCM also sends an output signal failure to the IPC indicating if the light operation has failed. The IPC will then display the appropriate indiction.
ITCM CAN-C inputs and outputs include the following:
CAN-C INPUTS
- Vehicle configuration data
- ESP brake data from the Brake System Control Module (BSCM)
- Central ADAS Decision Module (CADM) data
- Engine fuel type
- IPC odometer
- Electric brake feed
- Brake signal from the BSCM
- Turn and hazard lights OFF and ON requests
- Parking lights
- Trailer trip reset request
- Brake status
- Brake pedal status
- HSA status
- Vehicle speed
- BSCM torque data
CAN-C OUTPUTS
- IPC display requests
- Trailer brake status - check pass or fail
- Trailer brake control output signal to the trailer based on the brake pressure in the master cylinder and also based on the type of trailer and gain input from the user
- Trailer connection status and information signal
- Chime requests
- Trailer configuration data
- Trailer brake type
- Trailer brake PWM feed output value
- Trailer brake warning status
- Display request
- Trailer status
- Trailer odometer calculation for IPC
- Selected trailer number, name and type
- ITBS status
Body Control Module (BCM) inputs and outputs include:
CAN-C INPUTS
- Trailer configuration data
- Trailer status
- Display request
- ITBS status
- Chime request
- Gain status
- Trailer brake PWM feed output value
- Trailer brake type
- Trailer brake warning request
- Selected trailer
CAN-C OUTPUTS
- Ignition status
- Battery voltage
- IPC odometer
- Trailer configuration data
- Trailer status
- HSA status
- ESP data
- Trailer trip reset request
- Brake status
- Brake pedal status
- Vehicle speed signal
- BSCM torque data
- Selected trailer number and name from IPC
CAN-FD INPUTS
- IPC odometer
- Trailer trip reset request
CAN-FD OUTPUTS
- IPC display requests
- Chime request
- ITBS status
- Gain status
- Trailer brake PWM feed output value
- Trailer configuration data
- Trailer status
- Selected trailer number, name and type
- Trailer odometer calculation for IPC
| 1 - ITBS |
The ITBS is located in the steering column opening cover next to the console.
| 1 - Brake Lever |
| 2 - Gain Control Switch |
| 3 - ITBS |
There is a gain control switch and a manual sliding trailer brake lever under the adjustment switch powered by an 8-volt driver from the ITCM. The ITBS sends its signals to the ITCM. The ITBS is a serviceable component.
Automatic Braking - Based on ITBS inputs from the vehicle operator, the ITCM is capable of:
- Adjusting the gain depending on what the vehicle operator inputs via the ITBS adjustment switch
- Controlling the trailer brakes - electrical or EOH
- Calculating the output signals
- Diagnosing the elements involved and communicate information to the vehicle network
- Applying the brakes depending on the status of the ITBS manual lever
- Communicating the status of the braking and trailer to the Instrument Panel Cluster (IPC)
- Being selectable between electric brakes and EOH brakes
- Adjusting the aggressiveness based on what type of trailer is selected in the IPC
- Reacting to preemptive trailer sway events and during a trailer sway event to improve the control and braking of the vehicle
- Reacting during a Hill Start Assist (HSA) event to minimize the rollback feeling
- Helping to avoid the noise on the hitch during a stop and go
Manual Trailer Braking - In addition to automatic trailer braking, the user can manually apply the trailer brakes prior to or without the vehicle brakes by sliding the ITBS manual sliding brake lever to the left at any time.