Electronic Control Modules - Service Information: Overview Dodge Charger VI

DESCRIPTION

The primary on-board communication network between microprocessor-based electronic control modules in this vehicle is the Controller Area Network (CAN) data bus system. A data bus network minimizes redundant wiring connections; and, at the same time, reduces wire harness complexity, sensor current loads and controller hardware by allowing each sensing device to be connected to only one module (also referred to as a node). Each node reads, then broadcasts its sensor data over the bus for use by all other nodes requiring that data. Each node ignores the messages on the bus that it cannot use.

The CAN bus is a two-wire multiplex system. Multiplexing is any system that enables the transmission of multiple messages over a single channel or circuit. The CAN bus is used for communication between most vehicle nodes. However, in addition to the CAN bus network, certain nodes may also be equipped with a Local Interface Network (LIN) data bus. The LIN data bus is a single wire low-speed (9.6 Kbps) serial link bus used to provide direct communication between a LIN master module and certain switch or sensor inputs.

There are actually three separate CAN bus systems used in the vehicle. They are designated: the CAN-IHS, the CAN-C and the CAN-AT. The CAN-IHS and CAN-C systems provide on-board communication between all of the nodes that are connected to them. The CAN-C is the faster of the two systems providing near real-time communication (500 Kbps). The CAN-C is used typically for communications between more critical nodes, while the slower (125 Kbps). The CAN-IHS system is used for communications between less critical nodes.

The added speed of the CAN data bus is many times faster than previous data bus systems. This added speed facilitates the addition of more electronic control modules or nodes and the incorporation of many new electrical and electronic features in the vehicle.

The BCM is located under the instrument panel to right of the glove box. The central CAN gateway or hub module integral to the BCM is connected to CAN-IHS and CAN-C buses. This gateway physically and electrically isolates the CAN buses from each other and coordinates the bi-directional transfer of messages between them.

A third CAN bus on this vehicle is the CAN-AT (Audio and Telematics) Bus. The CTP Radio also known as the Telematics Gateway (TGW) transfers messages between the CAN-AT and CAN IHS buses. Examples of modules on the CAN-AT bus include the Amplifier, Integrated Center Stack (ICS) and the Hands Free Module (HFM). The TGW also stores DTCs for certain bus network faults.

All modules transmit and receive messages over one of these buses. Data exchange between the modules is achieved by serial transmission of encoded data messages (a form of transmission in which data bits are sent sequentially, one at a time, over a single line). Each module can both send and receive serial data simultaneously. Each data bit of a CAN Bus message is carried over the bus as a voltage differential between the two bus circuits which, when strung together, form a message. Each module uses arbitration to sort the message priority if two competing messages are attempting to be broadcast at the same time. Corruption of a single bit within a message will corrupt the entire message. Each message contains a Cyclic Redundancy Check (CRC) which specifies the message size exactly. If the message detected conflicts with the CRC the ECU receiving it will determine the message to be an error and consider that communication has not been possible. Diagnosis of this condition using a lab scope may reveal activity that appears to be Bus data messages even if no actual communication is possible. Communication problems that affect the whole bus, as a result of opens and terminal push outs are more likely to occur on data busses that operate at a high speed than a data bus that operates at a lower speed

OPERATION

The primary communication network between electronic control modules on this vehicle is the Controller Area Network (CAN) data bus system. The Controller Area Network (CAN) data bus allows all electronic modules connected to the bus to share information with each other. Regardless of whether a message originates from a module on the higher speed CAN C (500K) Bus or on the lower speed CAN Interior High Speed (IHS) (125K) Bus the message structure and layout is similar, which allows the Body Control Module (BCM) to be a Central GateWay to process and transfer messages between the CAN C and CAN IHS buses. The BCM also stores Diagnostic Trouble Codes (DTCs) for certain bus network faults. A third CAN bus on this vehicle is the CAN-AT (Audio and Telematics) Bus. The CTP Radio also known as the Telematics Gateway (TGW) transfers messages between the CAN-AT and CAN IHS buses. Examples of modules on the CAN-AT bus include the Amplifier, Integrated Center Stack (ICS) and the Hands Free Module (HFM). The TGW also stores DTCs for certain bus network faults.

All modules transmit and receive messages over one of these buses. Data exchange between the modules is achieved by serial transmission of encoded data messages (a form of transmission in which data bits are sent sequentially, one at a time, over a single line). Each module can both send and receive serial data simultaneously. Each data bit of a CAN Bus message is carried over the bus as a voltage differential between the two bus circuits which, when strung together, form a message. Each module uses arbitration to sort the message priority if two competing messages are attempting to be broadcast at the same time. Corruption of a single bit within a message will corrupt the entire message. Each message contains a Cyclic Redundancy Check (CRC) which specifies the message size exactly. If the message detected conflicts with the CRC the ECU receiving it will determine the message to be an error and consider that communication has not been possible. Diagnosis of this condition using a lab scope may reveal activity that appears to be Bus data messages even if no actual communication is possible. Communication problems that affect the whole bus, as a result of opens and terminal push outs are more likely to occur on data busses that operate at a high speed than a data bus that operates at a lower speed.

When an open circuit or terminal push out occurs one or more modules can become isolated from the remainder of the bus. The isolated module will attempt to communicate, but will not be able to receive messages or determine arbitration from other modules. Each time the isolated module attempts to communicate it alters the bus voltage on the intact bus circuit. Without functioning arbitration the isolated module alters the bus voltage while other bus messages are being sent thereby corrupting the messages on the remainder of the bus.

Note. All measurement of termination resistance is done with the vehicle battery disconnected.

The communication protocol being used for the CAN data bus is a non-proprietary, open standard adopted from the Bosch CAN Specification 2.0b. The CAN-C is the faster of the two primary buses in the CAN bus system, providing near real-time communication (500 Kbps). CAN-IHS and CAN-AT communicate at (125 Kbps).

The CAN bus nodes are connected in parallel to the two-wire bus using a twisted pair, where the wires are wrapped around each other to provide shielding from unwanted electromagnetic induction, thus preventing interference with the relatively low voltage signals being carried through them. The twisted pairs have between 33 and 50 twists per meter (yard). While the CAN bus is operating (active), one of the bus wires will carry a higher voltage and is referred to as the CAN High or CAN bus (+) wire, while the other bus wire will carry a lower voltage and is referred to as the CAN Low or CAN bus (-) wire. Refer to the CAN Bus Voltages table.

The CAN-IHS bus network remains active until all nodes on that network are ready for sleep. This is determined by the network using tokens in a manner similar to polling. When the last node that is active on the network is ready for sleep, and it has already received a token indicating that all other nodes on the bus are ready for sleep, it broadcasts a bus sleep acknowledgment message that causes the network to sleep. Once the CAN-IHS bus network is asleep, any node on the bus can awaken it by transmitting a message on the network. The BCM will keep either the CAN-IHS or the CAN-C bus awake for a timed interval after it receives a diagnostic message for that bus over the Diagnostic CAN-C bus.

In the CAN system, available options are configured into the BCM at the assembly plant, but additional options can be added in the field using the diagnostic scan tool. The configuration settings are stored in non-volatile memory. The BCM also has two 64-bit registers, which track each of the as-built and currently responding nodes on the CAN-B and CAN-C buses. The BCM stores a Diagnostic Trouble Code (DTC) in one of two caches for any detected active or stored faults in the order in which they occur. One cache stores powertrain (P-Code), chassis (C-Code) and body (B-Code) DTCs, while the second cache is dedicated to storing network (U-Code) DTCs.

Scheme 1

The A/C heater module (1) is a microprocessor designed to operate the heating and A/C system, using the Controller Area Network (CAN) data bus. The A/C heater module has a plastic housing with one integral electrical connector receptacle (3) and three mounting tabs (2 and 4).

The A/C heater module is located on the air inlet housing, on the passenger side of the vehicle.

The A/C heater module utilizes integrated circuitry and information carried over the Controller Area Network (CAN) data bus to monitor many sensors and switch inputs throughout the vehicle. In response to those inputs, the internal circuitry and programming of the A/C heater module allows it to control electronic functions and features of the heating and A/C system.

Some of the inputs received by the A/C heater module over the CAN bus are as follows

1. A/C Request
2. Ambient Air Temperature
3. Electric Back Light (EBL) Request
4. Electrical System Voltage
5. Engine Coolant Temperature
6. Engine Speed
7. Humidity, Windshield Glass Temperature and Dewpoint (ATC only)
8. Refrigerant Pressure
9. Vehicle Identification Number
10. Vehicle Odometer

Some of the messages broadcasted by the A/C heater module on the CAN bus are as follows

1. A/C Clutch Engage
2. Auto Headlamp Signal
3. EBL Status

The A/C heater module receives the following information over hardwired circuits

1. Auto Headlamp Signal
2. Evaporator Temperature
3. Interior Air Temperature
4. Left and Right Sun Load

The A/C heater module monitors and controls the following over hardwired circuits

1. Driver and Passenger Blend Door Positions
2. Blower Motor Speed
3. Mode Door Position
4. Recirculation Door Position

The A/C heater module is diagnosed using a scan tool. Prior to replacing an A/C heater module, run the calibration procedure to verify that the concern is not an air door calibration issue. Refer to STANDARD PROCEDURE .

The A/C heater module cannot be adjusted or repaired and must be replaced if inoperative or damaged.

The Active Damping Control Module (ADCM) uses the CAN bus to communicate with multiple modules. The ADCM has the following inputs: Vehicle Speed, Steering Angle Sensor (SAS) position, Throttle Position Sensor (TPS), Active Damping System (ADS) input switch, and 3 ADS sensors. There are solenoid-controlled ADS valving units on each shock absorber assembly which are the outputs for the ADCM.

The ADS input switch is a soft touch button on the radio display. When the ADS input switch is pressed with the key in the ON or RUN position, a signal is sent over the CAN bus to the ADCM and the Transmission Control Module (TCM) to change modes. The resulting change is indicated on the radio display.

The Active Damping Control Module (ADCM) controls the suspension and ride for the SRT version of this vehicle by adjusting the rebound and jounce of the shock assemblies using the above information and predetermined settings for maximum vehicle control. The shock absorbers are unique to the Active Damping System (ADS). Each shock absorber has a valving unit that is external, but still part of the shock absorber. Inside each valving unit are two solenoids that control the damping valves to alter the ride of the vehicle. The shocks are replaced as an assembly, they cannot be disassembled for repair.

The two front ADS sensors are mounted with one on each wheel well. The rear ADS sensor is mounted in the right rear wheel well on the shock tower. The ADCM is located in the left side of the trunk.

Two Mode ADS

Early build vehicles have a two mode Active Damping System (ADS), which consists of Auto and Sport Modes. The normal operating mode is Auto, and it is switched to and from Sport with the soft button on the radio display. When Sport is selected, ADS is activated and there is no change with the transmission programming.

Three Mode ADS

Later vehicles have a three mode Active Damping System (ADS), which consists of Auto, Sport, and Track modes. The normal operating mode is Auto, and it is switched to and from Sport or Track with the soft button on the radio display. If either Sport or Track is active during an ignition on-off-on cycle, the mode reverts to Sport. When Sport is selected, ADS is activated and there is no change with the transmission programming. When Track is selected, ADS and sport shifting in the transmission are activated.

The primary functions of the Antilock Brake Module (ABM) are to

1. Monitor the Antilock Brake System (ABS) and Electronic Stability Program (ESP) for proper operation.
2. Detect wheel locking or wheel slipping tendencies by monitoring the speed of all four wheels of the vehicle.
3. Control fluid modulation to the wheel brakes while the system is in ABS or traction control mode.
4. Modulates fluid pressure to the wheel brakes to control vehicle yaw rate in ESP mode.
5. Store diagnostic information.
6. Provide communication to the scan tool while in diagnostic mode.
7. Illuminate the amber TCS/ESP indicator in the instrument cluster.

The ABM constantly monitors the ABS and ESP (if equipped) for proper operation. If the ABM detects a fault, it will turn on the amber TCS/ESP indicator and disable the ABS or ESP if so equipped. The normal base braking system will remain operational at that time.

The ABM continuously monitors the speed of each wheel through the signals generated by the wheel speed sensors to determine if any wheel is beginning to lock. When a wheel locking tendency is detected, the ABM commands the ABM solenoid coils to actuate. The coils then open and close the valves in the HCU that modulate brake fluid pressure in some or all of the hydraulic circuits. The ABM continues to control pressure in individual hydraulic circuits until a locking tendency is no longer present.

The microprocessor-based electronic front door control modules (also known as a Driver Door Module/DDM, a Passenger Door Module/PDM or Front Door Multiplex/MUX Modules) contain logic circuits that monitor various hard wired low current, multiplexed inputs from the power window, power lock, power mirror and memory switches on their respective door. They also receive Controller Area Network (CAN) Interior High Speed (IHS) data bus electronic message-based external inputs from the opposing front door control module as well as from other electronic modules in the vehicle. The front door control modules also monitor hard wired power window motor Hall effect sensors and memory mirror position sensor inputs.

In addition, the front door control module on the driver side front door receives electronic message inputs from the driver side front door switch module over the Local Interface Network (LIN) data bus network. The program logic within the front door control module allows the microprocessor to prioritize all of these inputs and determine the tasks it needs to perform. These tasks are then completed either by controlling hard wired outputs to the various motors, actuators or lamps on its own or the rear doors, or by sending electronic message requests over the CAN-IHS bus to the appropriate electronic module in the vehicle.

The front door control modules are powered by a fused B(+) circuit and are grounded at all times so that they can operate regardless of the ignition switch position. Both driver and passenger door control modules provide active and stored Diagnostic Trouble Codes (DTC) through On-Board Diagnostics (OBD) and communicate with a diagnostic scan tool using the CAN data bus.

The hard wired inputs and outputs of the front door control module may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the electronic controls and communication between modules and other devices that provide some features of the power window, power lock, memory, interior lighting or exterior lighting system features the front door control modules provide. The most reliable, efficient and accurate means to diagnose the front door control modules or the electronic controls and communication related to operation of these systems requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

Scheme 2

1. Disconnect and isolate the battery negative cable.
2. Remove the trim panel from the inside of the front door. Refer to «PANEL, DOOR TRIM, REMOVAL»(ref-481397-S10143268672012062200000) .
3. Disconnect each of the electrical connectors (3) from the connector receptacles of the door control module (2).
4. Remove the two screws (4) that secure the door control module to the front door hardware module carrier (1).
5. Remove the door control module from the door hardware module carrier.

The Drivetrain Control Module (DTCM) controls the 4X4 transfer case shift functions via the actuation of a shift motor and utilizing the feedback of a mode sensor assembly. Communication is handled through the CAN bus. The user selectable transfer case modes include the following: 2WD, 4WD AUTO, 4WD LOCK, 4WD LOW, and Neutral (selections vary with the specific transfer case).

The DTCM is located in the drivers footwell, under the drivers foot rest.

During normal operation of an active transfer case the Drive Train Control Module (DTCM) control module learns and remembers the Clutch Engagement Point (Kiss Point), the position in the motor actuator's travel where torque begins to be transferred to the front wheels. The position is read out using the encoder as a 0 to 5 volt signal. This information is written into the module's EEPROM area at Ignition OFF. Over time the clutch pack wears and the Kiss Point changes in one direction (going from a lower voltage to a higher value).

NORMAL OPERATION

This mode is achieved by the ignition being switched in the RUN position, which powers up the 5V regulator and generates the appropriate RESET for the microprocessor. This mode also includes any required power-up system checks.

Multiple modules work together to improve vehicle steering assist at different rates at different speeds. At slow speeds (parking maneuvers) more assist is available and at high speeds less assist is available. The EHPS module uses the CAN - C data bus for inputs and outputs of the information necessary for operation. The use of a scan tool is necessary for diagnostics. EHPS module faults are stored in a diagnostic program memory and are accessible with the scan tool. Faults remain in memory until cleared, or until after the vehicle is started approximately 50 times. Stored faults are not erased if the battery is disconnected. For descriptions and procedures related to DTCs. Refer to DIAGNOSIS AND TESTING .

The Electro-Hydraulic Power Steering (EHPS) Pump assembly contains a control module, brushless electric motor, and hydraulic pump integrated into a single unit. The EHPS Pump draws power from the 12-Volt electrical system and provides the necessary flow and pressure to the steering gear to provide normal power steering. The output flow of the EHPS Pump is varied as a function of Steering Wheel Rate (received from SAS) and Vehicle Speed (received from ABS Module) in order to provide the optimum flow of power steering fluid to the steering gear under all operating conditions. The EHPS Pump will start to provide steering assist when the Vehicle speed message greater than 5 km/h (3 mph) is received on CAN C. If the Vehicle Speed message is missing at vehicle startup, the EHPS Pump will not operate. If the Vehicle Speed message is lost during operation the EHPS pump will use a default vehicle speed of 85 km/h (59 mph) to calculate desired flow and as a result, steering effort will no longer be speed sensitive. If the Steering Wheel Position message is lost the EHPS Pump will use a default steering wheel rate of 230°/sec to calculate desired flow and as a result, steering effort may be higher on evasive steering maneuvers. The EHPS pump will resume normal operation automatically once any missing message or out of range condition noted above is restored to normal.

The hands-free cellular system on this vehicle uses Bluetooth™ technology to provide wireless communication between the operator's compatible cellular telephone and the vehicle's on-board receiver.

The system uses voice recognition technology to control operation. The incoming voice is broadcast through the vehicle's radio speakers, automatically overriding any other audio signals on the front speakers when the hands-free system is in use. A microphone in the rearview mirror picks up vehicle occupant's voices.

The system will communicate with a telephone that is anywhere within the vehicle. However, covering the hand held phone or the hands-free phone module with a metal object may block the signal. The system will recognize up to a combine 10 phone and BTSA capable devices, each of which is given a spoken identification by the user during the setup process. The system includes Spanish and French voice recognition in addition to English.

The hands free module is located under the instrument panel to the left of the steering column mounted to the amplifier bracket.

Scheme 3

The Uconnect™ Phone Button (2) is used to get into the phone mode and make calls, show recent, incoming, outgoing calls, view phonebook etc., When you press the button you will hear a BEEP. The beep is your signal to give a command.

The Uconnect™ Voice Command Button (1) is only used for "barge in" and when you are already in a call and you want to send Tones or make another call.

The Voice Command button (1) is also used to access the Voice Commands for the Uconnect™ Voice Command features if your vehicle is equipped. Please see the Uconnect™ Voice Command information for direction on how to use the button.

The Uconnect™ Phone is fully integrated with the vehicle's audio system. The volume of the Uconnect™ Phone can be adjusted either from the radio volume control knob or from the steering wheel radio control (right switch), if so equipped.

Voice commands can be used to operate the Uconnect™ Phone and to navigate through the Uconnect™ Phone menu structure. Voice commands are required after most Uconnect™ Phone prompts.

The Heated Seat Module (HSM) controls the heated seat system, vented seat system and the heated steering wheel, depending on how equipped. The HSM is secured to a mounting bracket located under the front passenger seat. The HSM responds to heated and vented seat and heated steering wheel switch messages and ignition status inputs by controlling the 12 volt Direct Current (DC) output to the seat and steering wheel heating elements and front vented seat motors through integral solid-state relays.

When either of the front heated seat switches in the U-Connect Touch™ screen module are pressed, the module sends a message over the Controller Area Network (CAN) data bus to the HSM, signaling the HSM to energize the heating elements for the selected front seat. When equipped with rear heated seats, a request signal is sent to the HSM over a hard-wired circuit from the rear heated seat switch, to signal the HSM to supply power to the selected rear seat heating elements.

When either of the front vented seat switches in the U-Connect Touch™ screen module are pressed, the module sends a message over the CAN data bus to the HSM, signaling the HSM to operate the vented seat motors for the selected front seat.

When the heated steering wheel switch in the U-Connect Touch™ screen module is pressed, the module sends a message over the CAN data bus to the HSM, signaling the HSM to energize the heating element for the steering wheel.

The HSM energizes the integral solid-state relays that supply battery current to the heating elements. Heated seats turn off after 45 minutes of continuous operation. If high-level heating is selected, the control system will remain at the high level for 20 minutes and then drop to the low level. Normal heating cycle for the heated steering wheel is a minimum of 52 minutes.

The heated and vented seat and heated steering wheel system only operate when the ignition is in the Run position, and will turn off automatically whenever the ignition is set to any position other than Run.

The HSM is diagnosed using a scan tool. Refer to DIAGNOSIS AND TESTING . The HSM will automatically turn off the heating seat and steering wheel elements if it detects an open or low short in a heating element circuit. The HSM will automatically turn off the vented seat motors if it detects an open or low short in a vented seat motor circuit.

There are two different Integrate Center Stack (ICS) Screen Modules in the vehicle, a 4.3 inch (Base) and 8.4 inch (Mid). The ICS screens are located in the center of the instrument panel.

Scheme 4

The 8.4 inch (mid) (1) is a full touch screen for audio system and HVAC operations.

Scheme 5

The 4.3 inch (base) is a touch screen used in combination with hard keys for audio system and HVAC operations.

The Integrated Center Stack (ICS) screen is the user interface for many functions and features in the vehicle.

When the user selects a function on the ICS screen, the touch sends a message to the Telematics Gateway Module and then to the bus to the module related to the users input. The module then makes the changes requested by the users input and sends a message back to reflect the change has been made.

The following features can be accessed through the ICS screen

1. All Radio functions including CD/DVD
2. Media players
3. Satellite Radio, if equipped
4. GPS and navigation features, if equipped
5. Heated seats, if equipped
6. Climate controls
7. Bluetooth functions, if equipped
8. Personal convenience options
9. Dealer Mode

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

Scheme 12

1. Disconnect the negative battery cable.
2. Remove the instrument cluster bezel retainer (1) and remove the bezel (2). Refer to «BEZEL, INSTRUMENT CLUSTER, REMOVAL»(ref-481397-S01329917622012062200000) .
3. Disconnect the harness connectors (2 & 3) from the rear of the Integrated Center Stack (ICS) screen module (1) to allow better access to the 40 - way connector. CAUTION: Push the 40 way connector in before pushing on the locking clip. Failure to follow these instructions will damage or break the connector locking clip. NOTE: In the event that the locking tab breaks or is broken, do not replace the harness. The connector will still lock and the harness will still function as designed. CAUTION: Never pull the connector out by the wires. Failure to follow these instructions will damage or break the wires and/or connector.
4. Push in on the 40 - way connector (1).
5. Gently push down on the connector release lock (1).
6. Using a pocket screw driver or a trim stick (special tool #C-4755, Trim Stick) or equivalent (1), gently pry on one side of the connector (2).
7. Using a pocket screw driver or a trim stick (special tool #C-4755, Trim Stick) or equivalent (1), gently pry on the other side of the connector (2).
8. Use steps 7 and 8 until the connector is out far enough to grab the connectors with your fingers.
9. Remove the retainers (1) and remove the (ICS) screen module from the instrument panel bezel.

Scheme 13

Scheme 14

1. Disconnect the negative battery cable.
2. Remove the instrument cluster bezel retainer (1) and remove the bezel (2). Refer to «BEZEL, INSTRUMENT CLUSTER, REMOVAL»(ref-481397-S01329917622012062200000) .
3. Disconnect the harness connectors (2 & 3) from the rear of the Integrated Center Stack (ICS) screen module (1) to allow better access to the 40 - way connector. CAUTION: Push the 40 way connector in before pushing on the locking clip. Failure to follow these instructions will damage or break the connector locking clip. NOTE: In the event that the locking tab breaks or is broken, do not replace the harness. The connector will still lock and the harness will still function as designed. CAUTION: Never pull the connector out by the wires. Failure to follow these instructions will damage or break the wires and/or connector.
4. Push in on the 40 - way connector (1).
5. Gently push down on the connector release lock (1).
6. Using a pocket screw driver or a trim stick (special tool #C-4755, Trim Stick) or equivalent (1), gently pry on one side of the connector (2).
7. Using a pocket screw driver or a trim stick (special tool #C-4755, Trim Stick) or equivalent (1), gently pry on the other side of the connector (2).
8. Use steps 7 and 8 until the connector is out far enough to grab the connectors with your fingers.
9. Remove the retainers (1) and remove the (ICS) screen module (2) from the instrument panel bezel.

The Memory Seat Module (MSM) receives battery current through a circuit breaker in the Power Distribution Center (PDC). The memory system remains operational, regardless of the ignition position. When the driver memory switch button or FOBIK transmitter button (when programmed) is pushed, a signal is sent to the MSM over the Controller Area Network (CAN) data bus. The MSM is responsible for the 12 volt Direct Current (DC) feed and ground path to the power seat adjuster motors and to the other memory system components.

The MSM also receives hard-wired input from the hall effect sensors, mounted on each of the driver power seat adjuster motors, driver side view mirror motors, power adjustable steering column motors and power adjustable pedal motor, when equipped. The programmed software in the MSM allows it to know where the driver seat, mirror, steering column and pedals, as equipped, are located in there designed travel by a pulse count, generated from hall effect sensors. This way, when a memory seat switch is pressed the MSM will power these components until the correct preset location is achieved. The MSM will prevent the seat memory recall function from being initiated, if the transmission gear selector is not in the Park position. These inputs are monitored over the CAN bus by the MSM.

A memory setting is saved by pressing the "Set" button, then pressing either the memory "1" or "2" button within five seconds of pressing the "Set" button.

A memory setting is recalled by pressing either the memory "1" or "2" button, or by pressing the unlock button on a "linked" FOBIK transmitter.

The MSM performs the following functions

1. Positions the driver power seat (fore/aft, up/down, tilt and recline positions).
2. Sends the memory save or recall (number 1 or number 2) command over the CAN bus circuit to the other memory system components, radio station pre-sets and power mirror positions.
3. Provides for the easy entry/exit feature.

When a memory button is pressed (number 1 or number 2) on the memory seat switch, it provides resistive signal to the MSM. The MSM will then position the driver seat to the pre-set location. When a FOBIK transmitter button is pressed, depending on which transmitter (number 1 or number 2), the WIN/SKIM receiver sends the recall request and FOBIK number (number 1 or number 2) data message. The FOBIK transmitter function depends on if the MSM is programmed to trigger the recall (linked FOBIKs).

A FOBIK is "linked" to a memory setting by pressing the "Set" button and then pressing either the memory "1" or "2" button within 5 seconds of pressing the set button, then by pressing the "lock" button on the selected FOBIK.

The memory seat system "Easy Entry and Exit" feature provides the driver with more room to enter or exit the vehicle. When the driver seat is in a memorized position, it will move rearward 55 millimeters (2.2 inches) or to the end of its travel, whichever occurs first, when the ignition is pressed to OFF. The seat will return to the pre-set position when the ignition is pressed to RUN.

The memory seat system "learns" the seat, mirror, column and pedal motors maximum end positions, when the motor reaches the limit of travel in any direction and stalls. Subsequently, movement will stop just short of that position to avoid extra stress on the motors and mechanisms. If the system learned a maximum position as a result of an obstruction, as for instance if a large object was placed on the floor behind the seat, the system can relearn the "true" maximum position through manually operating the power seat after the obstruction is removed.

Note. It is normal for the power accessories contained in the memory system to stop at the maximum "learned" position and then continue to the "true" maximum position when the control switch is released and then applied in the same direction a second time.

Certain functions and features of the memory seat system rely upon resources shared with other electronic modules in the vehicle over the CAN bus. The CAN bus allows the sharing of sensor information. This helps to reduce wire harness complexity, internal controller hardware and component sensor current loads. At the same time, the memory seat system provides increased reliability, enhanced diagnostics and allows the addition of new feature capabilities.

Note. Anytime a Memory Seat Module (MSM) or a driver power seat motor or seat track is replaced, the MSM must be cleared of all learned parameters using a scan tool and the Power Seat System Verification test must be performed.

The use of a scan tool is needed for diagnosis of the MSM, CAN bus and other electronic modules. Refer to DIAGNOSIS AND TESTING .

MODES OF OPERATION

As input signals to the Powertrain Control Module (PCM) change, the PCM adjusts its response to the output devices. For example, the PCM must calculate different injector pulse width and ignition timing for idle than it does for wide open throttle (WOT).

The PCM will operate in two different modes: Open Loop and Closed Loop .

During Open Loop modes, the PCM receives input signals and responds only according to preset PCM programming. Input from the oxygen (O2S) sensors is not monitored during Open Loop modes.

During Closed Loop modes, the PCM will monitor the oxygen (O2S) sensors input. This input indicates to the PCM whether or not the calculated injector pulse width results in the ideal air-fuel ratio. This ratio is 14.7 parts air-to-1 part fuel. By monitoring the exhaust oxygen content through the O2S sensor, the PCM can fine tune the injector pulse width. This is done to achieve optimum fuel economy combined with low emission engine performance.

The fuel injection system has the following modes of operation

1. Ignition switch ON
2. Engine start-up (crank)
3. Engine warm-up
4. Idle
5. Cruise
6. Acceleration
7. Deceleration
8. Wide open throttle (WOT)
9. Ignition switch OFF

The ignition switch On, engine start-up (crank), engine warm-up, acceleration, deceleration and wide open throttle modes are Open Loop modes. The idle and cruise modes, (with the engine at operating temperature) are Closed Loop modes.

There are 5 other component categories that make up the new ignition system.

The components are

1. Radio Frequency (RF) HUB (1)
2. LF Antennas (5)
3. FOB (2, 4 for Police)
4. Special Door Handles (2)
5. Special Liftgate Handle (1)

This new ignition system operation begins when an owner approaches their vehicle with a FOB somewhere on their person or belongings, i.e., in their gym bag. When the owner touches the handle to pull the door open, door handle electronics signal the RF HUB with a "request to open". The RF HUB uses all of the 5 LF (low frequency) antennas to communicate with the FOB. Once located, the FOB's response is evaluated by the RF HUB to determine if the person pulling on the door handle is in fact the owner. This process completes 'FOB authentication'.

Once authentication is successfully completed, the RF HUB requests the Body Control Module (BCM) to unlock the affected door. Once the doors unlock, the owner is then free to continue pulling the door handle in an attempt to enter their vehicle. This process of opening the door without actively using a FOB or key is called 'passive entry'. The LD/LX trunk handle is outfitted with a passive entry switch, allowing the trunk to pop open when it's pressed after FOB authentication completes successfully.

After the vehicle's owner is buckled, the customer then pushes the KIN's SSB (Keyless Ignition Node's Start/Stop Button) while pushing the brake pedal as if braking while coming to a stoplight. (For manual transmission vehicles the clutch pedal is depressed instead of the brake pedal to initiate a start procedure). Before the vehicle is allowed to start, another 'FOB authentication' cycle must be completed. Once successfully completed, the RF HUB next sends the BCM the ignition switch position, which equates to a 'request to start' command. The process of starting a vehicle without the act of using a bladed key or FOB is called 'Keyless Go'.

The passive entry works when the FOB can be located outside the vehicle using the LF antennas. Keyless go operates when the RF HUB can locate the FOB inside the vehicle. Please refer to the owner's manual for more information on authentication zones.

After putting the vehicle into park, pushing the KIN's SSB allows the vehicle's engine to be shut off. In an emergency, pressing the SSB continuously for 2 seconds or repeatedly (one hit every 30- 500msec) shuts off the engine.

Scheme 15

1. Disconnect the negative battery cable.
2. Remove the rear shelf cover. Refer to «PANEL, REAR SHELF, REMOVAL»(ref-481397-S39394376072012062200000) .
3. Remove the RF Hub retainers (1).
4. Disconnect the electrical connectors (2).
5. If equipped, disconnect the remote start antenna (3).
6. Remove the RF Hub (4) from the vehicle.

The Steering Column Control Module (SCCM) includes an electronic circuit board, sometimes referred to as the Steering Control Module (SCM). The SCM is a Local Interface Network (LIN) bus master and a gateway for the Controller Area Network (CAN) data bus. Refer to COMMUNICATION, DESCRIPTION .

The microprocessor-based SCM provides power and ground to the multi-function and power tilt and telescope steering column switches of the SCCM, then utilizes integrated circuitry to monitor hard wired analog and digital return inputs from both of these switches. Except for the circuits for the optional heated steering wheel and the standard equipment Driver AirBag (DAB), which are pass-through circuits of the SCCM, the SCM also provides power and ground to all of the electronics carried on the steering wheel through a microprocessor contained in the right steering wheel switch, which is also a LIN slave.

The steering wheel-mounted electronics monitored by the SCM include the horn switch, the speed control switches, the remote radio switches, the hands-free communication switches and the Electronic Vehicle Information Center (EVIC) control switches, if the vehicle is so equipped. The LIN slave monitors the changing states of these switches through both hard wired analog and digital return inputs, then communicates those switch states to the SCM over the LIN bus. In response to those inputs, the internal circuitry of the SCM gateway then transmits electronic message outputs communicating all of the monitored switch state changes as well as SAS data to other electronic modules in the vehicle over the CAN bus.

A fixed connector receptacle of the SCCM connects the SCM to the vehicle electrical system through a single take out with connector from the instrument panel wire harness. The instrument panel wire harness take out has been intentionally provided with additional length to facilitate service removal and installation of the SCCM. However, following SCCM installation, this additional length must be pulled back and secured to the instrument panel structure to prevent the potential for undesirable rattling or buzzing noises while driving.

The SCM is connected to a fused B(+) circuit and receives a path to ground at all times. These connections allow it to remain functional regardless of the ignition switch position. Any input to the SCM that controls a vehicle system function that does not require that the ignition switch be in the ON position such as depressing the horn switch, prompts the SCM to wake up and transmit on the CAN data bus.

The service replacement SCCM is shipped with the clockspring pre-centered within the SCCM and with a plastic locking tab installed. This locking tab should not be removed until the SCCM has been properly installed on the steering column. If the locking tab is removed before the steering wheel is installed on a steering column, clockspring centering must be confirmed by viewing the inspection window on the clockspring rotor. If the black boxes of the clockspring tape are not visible in the inspection window, the entire SCCM must be replaced with a new unit. Refer to CLOCKSPRING, STANDARD PROCEDURE . Proper clockspring installation may also be confirmed by viewing the Steering Angle Sensor (SAS) data using a diagnostic scan tool.

The hard wired circuits between components related to the SCM may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the SCCM, the SCM or the electronic controls or communication between modules and other devices that provide some features of the SCCM. The most reliable, efficient, and accurate means to diagnose the SCCM, the SCM or the electronic controls and communication related to SCCM or SCM operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

The Telematics Gateway Module (TGM) is responsible for the displayed information on the Integrated Center Stack (ICS) Screen Module over the CAN-AT bus.

The user input from the ICS Screen Module sends the information over the CAN-AT to the TGM, the TGM then sends the command out to the CAN-I bus to the requested module. The requested module then makes the changes requested by the users input and sends a message back to the TGM, the TGM then send the message over the CAN-AT to the ICS to reflect the users input selection has been activated and or changed.

The TGM is responsible for the following.

1. Displaying information on the Integrated Center Stack (ICS) Screen Module.
2. Passing user input to the correct module on the CAN bus.
3. Turning the specific areas (buttons) on the screen usable for user interaction.
4. CD/DVD operations
5. SD card operations (Mid level only)

If the screen displays "Shipping Mode" . Refer to STANDARD PROCEDURE .

The microcontroller-based electronic Vehicle System Interface Module (VSIM) (also known as the Vehicle Systems Integration Module/VSIM or the aftermarket module) contains the electronic logic circuitry and software that enable many of the aftermarket equipment and systems typically installed on police or fleet vehicles to communicate with and be integrated with the electronic control modules and features already installed in the vehicle. The VSIM can communicate with aftermarket modules or with other electronic modules in the vehicle using the Controller Area Network (CAN) data bus.

The VSIM is powered by a fused B(+) circuit and is grounded at all times so that it can operate regardless of the ignition switch position. The module awakens or sleeps based upon the status of the CAN data bus network. The module monitors both active and stored Diagnostic Trouble Codes (DTC) through On-Board Diagnostics (OBD) and communicates with a diagnostic scan tool using the CAN data bus.

The hard wired inputs and outputs of the VSIM may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the electronic controls and communication between modules and other devices that provide some features of the VSIM. The most reliable, efficient and accurate means to diagnose the VSIM or the electronic controls and communication related to operation of the aftermarket systems connected through the VSIM requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

There are 5 other component categories that make up the new ignition system.

The components are

1. Radio Frequency (RF) HUB (1)
2. LF Antennas (5)
3. FOB (2, 4 for Police)
4. Special Door Handles (2)
5. Special Liftgate Handle (1)

This new ignition system operation begins when an owner approaches their vehicle with a FOB somewhere on their person or belongings, i.e., in their gym bag. When the owner touches the handle to pull the door open, door handle electronics signal the RF HUB with a "request to open". The RF HUB uses all of the 5 LF (low frequency) antennas to communicate with the FOB. Once located, the FOB's response is evaluated by the RF HUB to determine if the person pulling on the door handle is in fact the owner. This process completes 'FOB authentication'.

Once authentication is successfully completed, the RF HUB requests the Body Control Module (BCM) to unlock the affected door. Once the doors unlock, the owner is then free to continue pulling the door handle in an attempt to enter their vehicle. This process of opening the door without actively using a FOB or key is called 'passive entry'. The LD/LX trunk handle is outfitted with a passive entry switch, allowing the trunk to pop open when it's pressed after FOB authentication completes successfully.

After the vehicle's owner is buckled, the customer then pushes the KIN's SSB (Keyless Ignition Node's Start/Stop Button) while pushing the brake pedal as if braking while coming to a stoplight. (For manual transmission vehicles the clutch pedal is depressed instead of the brake pedal to initiate a start procedure). Before the vehicle is allowed to start, another 'FOB authentication' cycle must be completed. Once successfully completed, the RF HUB next sends the BCM the ignition switch position, which equates to a 'request to start' command. The process of starting a vehicle without the act of using a bladed key or FOB is called 'Keyless Go'.

The passive entry works when the FOB can be located outside the vehicle using the LF antennas. Keyless go operates when the RF HUB can locate the FOB inside the vehicle. Please refer to the owner's manual for more information on authentication zones.

After putting the vehicle into park, pushing the KIN's SSB allows the vehicle's engine to be shut off. In an emergency, pressing the SSB continuously for 2 seconds or repeatedly (one hit every 30- 500msec) shuts off the engine.

The microprocessor in the adaptive speed control sensor (also known as the Adaptive Cruise Control/ACC sensor or module, or as the radar sensor or module) contains the logic circuits and controls many of the features of the adaptive speed control system. The ACC sensor receives battery voltage on a fused ignition switch output (run) circuit and is grounded at all times through a hard wired remote ground point. These connections allow the ACC sensor to operate only when the ignition switch is in the ON position. Likewise, the ACC sensor sleeps whenever the ignition switch is in any position except ON.

The ACC sensor is also a RAdio Detection And Ranging (RADAR) transceiver. The ACC sensor transmits electromagnetic signal bursts at an operating frequency of 77 gigahertz. Those signal bursts are scattered by any objects they strike within the 40 degree field of view of the transceiver, which changes the strength and frequency of the signal. The ACC sensor antenna receives and interprets the returned signals to detect any objects in the path of the vehicle as well as their speed and direction.

The ACC sensor receives electronic speed control switch status message inputs from the Steering Control Module (SCM) integral to the Steering Column Control Module (SCCM) over the Controller Area Network (CAN) data bus. The sensor also monitors electronic message inputs from the Powertrain Control Module (PCM), the Antilock Brake Module (ABM) (also known as the Controller Antilock Brake/CAB or the Electronic Stability Control/ESC module) and the Transmission Control Module (TCM).

The ACC sensor logic processes all of those inputs, then provides the appropriate electronic message outputs over the CAN data bus to the PCM, the TCM and the ABM to control and maintain the separation setting selected by the vehicle operator between the vehicle and any preceding vehicles. The ACC sensor also provides electronic message outputs to the instrument cluster and the Electronic Vehicle Information Center (EVIC) to invoke the Forward Collision Warning (FCW) features.

Among other features, the sensor also contains an electronic ambient temperature sensor and a heating element. When appropriate ambient temperatures are sensed, the heating element is energized by the sensor control circuitry to keep the sensor lens or radar dome clear of ice and snow accumulations that might otherwise blind the sensor to proper reception of returned signals.

The ACC sensor microprocessor continuously monitors all of its internal electronics to determine the sensor readiness. If the ACC sensor detects a monitored sensor fault, it sets and stores a Diagnostic Trouble Code (DTC). The ACC sensor uses On-Board Diagnostics (OBD) and can communicate with other electronic modules in the vehicle as well as with the diagnostic scan tool using the CAN data bus. This method of communication is used for control of the indicators and indications provided to the vehicle operator through the instrument cluster and the EVIC. The ACC sensor is also Flash programmable, allowing the sensor software to be updated using a diagnostic scan tool.

The hard wired inputs for the ACC sensor may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the ACC sensor or the electronic controls or communication between other modules and devices that provide features of the adaptive speed control and FCW system features. The most reliable, efficient, and accurate means to diagnose the ACC sensor or the electronic controls and communication related to adaptive speed control or FCW system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.