SAM chassis module failure - Great!

What kind of truck is this and what does SAM stand for?

 

Surface-to-Air Missile

 

Same thing you always get from Mexico or China: Sorry A ** Manufactured parts...

 

LOL, those are good ones!

 

SAM (Signal detection
and Actuation Module)​

The Cascadia has two SAMs​

SAM Chassis ECU
SAM - Cabin ECU
Starpoint Connector
Central Gateway ECU

[SIZE=3]Modular Switch Field (MSF) ECU[/SIZE]​

[FONT=HelveticaNeue-MediumCond][SIZE=2][FONT=HelveticaNeue-MediumCond][SIZE=2]And to get on the tech side of it:[/SIZE][/FONT][/SIZE][/FONT]
[FONT=HelveticaNeue-MediumCond][SIZE=2]
[LEFT][SIZE=2][FONT=HelveticaNeue-MediumCond][SIZE=2][FONT=HelveticaNeue-MediumCond][SIZE=2][FONT=HelveticaNeue-MediumCond]Cascadia HVAC Operation[/FONT][/SIZE][/FONT][/SIZE][SIZE=2][FONT=HelveticaNeue-MediumCond][/FONT][/SIZE][/FONT][/SIZE][/LEFT][SIZE=2][FONT=HelveticaNeue-MediumCond][SIZE=2][FONT=HelveticaNeue-MediumCond]

[LEFT][/LEFT][/FONT][LEFT][/left][/SIZE][LEFT][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]The new Freightliner Cascadia is equipped with a multiplexed[/SIZE][/FONT][/SIZE][/FONT]
[SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]electronic control system. Put simply, multiplexed electronic[/FONT][/SIZE][/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]controls share information with each other. The information[/FONT][/SIZE][/FONT][/SIZE][SIZE=4][FONT=HelveticaNeue-LightCond]
[SIZE=4][FONT=HelveticaNeue-LightCond]from input devices wired to one control module is broadcast[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]over a databus so that information may be used by another[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]control module. Most of the electrical systems on the truck are furnished battery[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]power, ignition power, accessory power and ground by two Signal detection and[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]Actuation Modules, a.k.a SAMs. These two SAMs, the Cabin SAM[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]and the Chassis SAM also control most of the electrical features of the truck.[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]What does this have to do with the heating and air conditioning system you might[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]ask? The answer is that these SAMs also receive inputs from switches and sensors[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]on the truck and use that information to control outputs that are wired to the[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]SAMS. They also transmit that information on a Controller Area Network (CAN)[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]databus called the Cabin CAN. Some of this information is used by the air conditioning[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]control modules, called the Front Control Unit (FCU) and the Auxiliary[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]Control Unit (ACU), to control the air conditioning and heating system.[/FONT][/SIZE][/FONT][/SIZE][/LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]

[LEFT][/LEFT][/FONT][LEFT][/left][/SIZE][LEFT][FONT=HelveticaNeue-BlackCond][SIZE=4][FONT=HelveticaNeue-BlackCond][SIZE=4]Cabin CAN Operation[/SIZE][/FONT][/SIZE][/FONT]
[FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]The Cabin CAN databus connects four modules on the truck. They are the Cabin[/SIZE][/FONT][/SIZE][/FONT]
[SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]Sam, Chassis SAM, Modular Switch Field (MSF) master, and the Central Gateway[/FONT][/SIZE][/FONT][/SIZE][SIZE=4][FONT=HelveticaNeue-LightCond]
[SIZE=4][FONT=HelveticaNeue-LightCond]Module (CGW). The Cabin Can connects all four of these modules to a Starpoint[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]Connector. This connector is a junction box that ties all these sections of the Cabin[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]CAN together. The Central Gateway Module that is connected to[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]the Cabin CAN translates the information on the Cabin CAN databus and routes it[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]to other databusses that are connected to other modules such as the two air conditioning[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]control modules (FCU and ACU). For example, the two air conditioning[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]control modules, the FCU and ACU, communicate on the J-1939 databus. They[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]receive information that is broadcast by the Cabin SAM after the information is[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]translated the by Central Gateway Module and sent out over the J-1939 databus.[/FONT][/SIZE][/FONT][/SIZE][/LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]

[/FONT][/SIZE][FONT=ZapfDingbats][SIZE=4][COLOR=#f03329][FONT=ZapfDingbats][SIZE=4][COLOR=#f03329][FONT=ZapfDingbats][SIZE=4][COLOR=#f03329] [/COLOR][/SIZE][/FONT]
[LEFT][/LEFT][/COLOR][LEFT][/left][/SIZE][LEFT][/left][/FONT][LEFT][/left][/COLOR][LEFT][/left][/SIZE][LEFT][/left][/FONT][LEFT][FONT=HelveticaNeue-BlackCond][SIZE=4][FONT=HelveticaNeue-BlackCond][SIZE=4]Cabin SAM Inputs and Outputs[/SIZE][/FONT][/SIZE][/FONT][/LEFT]

[LEFT][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]Several inputs received from sensors wired to the Cabin SAM are used for[/SIZE][/FONT][/SIZE][/FONT][/LEFT]

[SIZE=4][FONT=HelveticaNeue-LightCond][LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]HVAC control. These four inputs are: Ambient Temperature, High Side Refrigerant[/FONT][/SIZE]
[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]Pressure, Park Brake Status, and Low Air Pressure Status. The[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]Cabin SAM not only receives inputs but also controls outputs such as the AC[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]compressor clutch. The AC compressor clutch receives power and ground[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]from the Cabin Sam. [/FONT][/SIZE][SIZE=4][FONT=HelveticaNeue-LightCond]The information used to [/FONT][/SIZE][SIZE=4][FONT=HelveticaNeue-LightCond]determine whether the engagement [/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]rules are met comes from several sources.[/FONT][/SIZE][/LEFT][/LEFT][/FONT][LEFT][LEFT][/left][/left][/SIZE][LEFT][LEFT][/LEFT]
[/LEFT]
[SIZE=4][FONT=HelveticaNeue-LightCond]


[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]The [/FONT][/SIZE][/LEFT]

[/FONT][/SIZE][LEFT][LEFT][I][FONT=HelveticaNeue-MediumCondObl][SIZE=4][FONT=HelveticaNeue-MediumCondObl][SIZE=4]Blower Speed [/SIZE][/FONT][/SIZE][/FONT][/I][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]switch and the [/SIZE][/FONT][/SIZE][/FONT][I][FONT=HelveticaNeue-MediumCondObl][SIZE=4][FONT=HelveticaNeue-MediumCondObl][SIZE=4]AC switch [/SIZE][/FONT][/SIZE][/FONT][/I][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]are mounted in the FCU. The[/SIZE][/FONT][/SIZE][/FONT][/LEFT]



[LEFT][I][FONT=HelveticaNeue-MediumCondObl][SIZE=4][FONT=HelveticaNeue-MediumCondObl][SIZE=4]Countdown Timers [/SIZE][/FONT][/SIZE][/FONT][/I][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]are in software programmed into the FCU. [/SIZE][/FONT][/SIZE][/FONT][/LEFT]

[LEFT][I][FONT=HelveticaNeue-MediumCondObl][SIZE=4][FONT=HelveticaNeue-MediumCondObl][SIZE=4]Air Pressure[/SIZE][/FONT][/SIZE][/FONT][/I][/LEFT]

[LEFT][SIZE=4][FONT=HelveticaNeue-MediumCondObl][I][SIZE=4][FONT=HelveticaNeue-MediumCondObl]Status [/FONT][/SIZE][/I][/FONT][/SIZE][/LEFT]


[LEFT][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]is broadcast by the Cabin Sam from information it receives from Primary[/SIZE][/FONT][/SIZE][/FONT][/LEFT]

[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]and Secondary air pressure switches that are wired to the Cabin SAM. [/FONT][/SIZE][/FONT][/SIZE][/LEFT]


[LEFT][I][FONT=HelveticaNeue-MediumCondObl][SIZE=4][FONT=HelveticaNeue-MediumCondObl][SIZE=4]Engine[/SIZE][/FONT][/SIZE][/FONT][/I][/LEFT]

[LEFT][SIZE=4][FONT=HelveticaNeue-MediumCondObl][I][SIZE=4][FONT=HelveticaNeue-MediumCondObl]RPM [/FONT][/SIZE][/I][/FONT][/SIZE][/LEFT]


[LEFT][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]is broadcast over the J-1939 databus by the Engine's Common Powertrain[/SIZE][/FONT][/SIZE][/FONT][/LEFT]

[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]Controller (CPC) that is mounted behind the center dash panel. The CPC receives[/FONT][/SIZE]

[SIZE=4][FONT=HelveticaNeue-LightCond]engine RPM from the Motor Control Module (MCM) that is mounted on the left[/FONT][/SIZE]
[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]side of the engine. The CPC and MCM communicate with each other over a[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]proprietary databus called the Engine CAN. [/FONT][/SIZE][/LEFT]
[/FONT][/SIZE][/LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]
[/FONT][/SIZE]



[LEFT][I][FONT=HelveticaNeue-MediumCondObl][SIZE=4][FONT=HelveticaNeue-MediumCondObl][SIZE=4]Ambient Temperature [/SIZE][/FONT][/SIZE][/FONT][/I][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]and [/SIZE][/FONT][/SIZE][/FONT][I][FONT=HelveticaNeue-MediumCondObl][SIZE=4][FONT=HelveticaNeue-MediumCondObl][SIZE=4]High[/SIZE][/FONT][/SIZE][/FONT][/I][/LEFT]

[LEFT][SIZE=4][FONT=HelveticaNeue-MediumCondObl][I][SIZE=4][FONT=HelveticaNeue-MediumCondObl]Side Refrigerant Pressure [/FONT][/SIZE][/I][/FONT][/SIZE][/LEFT]


[LEFT][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]are broadcast by the Cabin Sam from information[/SIZE][/FONT][/SIZE][/FONT][/LEFT]

[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]received by sensors wired to the Cabin Sam. The Ambient Temperature sensor[/FONT][/SIZE]

[SIZE=4][FONT=HelveticaNeue-LightCond]is mounted behind the front bumper at the end of the right frame rail. The High[/FONT][/SIZE]
[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]Side Refrigerant Pressure sensor is mounted in the high side refrigerant line in[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]front of the cab frontwall in the engine compartment. [/FONT][/SIZE][/LEFT]
[/FONT][/SIZE][/LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]
[/FONT][/SIZE]



[LEFT][I][FONT=HelveticaNeue-MediumCondObl][SIZE=4][FONT=HelveticaNeue-MediumCondObl][SIZE=4]Battery Voltage [/SIZE][/FONT][/SIZE][/FONT][/I][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]is sensed[/SIZE][/FONT][/SIZE][/FONT][/LEFT]

[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]internally in the Cabin Sam. [/FONT][/SIZE][/FONT][/SIZE][/LEFT]


[LEFT][I][FONT=HelveticaNeue-MediumCondObl][SIZE=4][FONT=HelveticaNeue-MediumCondObl][SIZE=4]Evaporator Temperature [/SIZE][/FONT][/SIZE][/FONT][/I][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]is sensed by the FCU from[/SIZE][/FONT][/SIZE][/FONT][/LEFT]

[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]a temperature sensor that is located next to the evaporator in the front HVAC unit.[/FONT][/SIZE]

[SIZE=4][FONT=HelveticaNeue-LightCond]This sensor measures the temperature of the air coming off the evaporator.[/FONT][/SIZE]
[LEFT][/LEFT]
[/FONT][/SIZE][/LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]
[/FONT][/SIZE][LEFT][FONT=HelveticaNeue-BlackCond][SIZE=4][FONT=HelveticaNeue-BlackCond][SIZE=4]Engine Fan Operation[/SIZE][/FONT][/SIZE][/FONT]
[LEFT][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]The engine fan is controlled by the Motor Control Module (MCM). The MCM[/SIZE][/FONT][/SIZE][/FONT]
[SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]engages and releases the engine fan based on information it receives from its[/FONT][/SIZE][/FONT][/SIZE][SIZE=4][FONT=HelveticaNeue-LightCond]
[SIZE=4][FONT=HelveticaNeue-LightCond]own sensors, but it also has to control the fan based on databus information[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]it receives from the FCU and the Cabin Sam. When the refrigerant pressure[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]sensed by the Cabin Sam becomes high enough that the engine fan needs to be[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]turned on, the FCU sends a request to the CPC over the J-1939 databus. The[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]CPC sends a command to the MCM over the Engine CAN databus and the MCM[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]engages the engine fan. The engine fan On Time varies with vehicle speed and[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]park brake status . Vehicle Speed is sensed by the Vehicle Speed[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]Sensor that is wired to the CPC. The CPC broadcasts Vehicle Speed over the[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]J-1939 databus and it is received by the FCU. Park Brake Status is broadcast[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]by the Cabin Sam from information it receives from a Park Brake switch that is[/FONT][/SIZE]
[SIZE=4][FONT=HelveticaNeue-LightCond]wired to it. Engine Fan On-Time logic is programmed into the FCU.[/FONT][/SIZE]
[/FONT][/SIZE][FONT=HelveticaNeue-BlackCond][SIZE=4][FONT=HelveticaNeue-BlackCond][SIZE=4]Conclusion[/SIZE][/FONT][/SIZE][/FONT]
[FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4]Technicians who diagnose control issues on this system have to understand[/SIZE][/FONT][/SIZE][/FONT]
[SIZE=4][FONT=HelveticaNeue-LightCond][SIZE=4][FONT=HelveticaNeue-LightCond]where the information comes from, and which control module is controlling[/FONT][/SIZE][/FONT][/SIZE][SIZE=4][FONT=HelveticaNeue-LightCond]
[SIZE=4][FONT=HelveticaNeue-LightCond]what.[/FONT][/SIZE][/FONT][/SIZE][SIZE=4][FONT=HelveticaNeue-LightCond][/FONT][/SIZE][/LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]
[/font][/size][/LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]

[LEFT][SIZE=4][FONT=HelveticaNeue-LightCond]Now you know what a SAM is [/FONT][/SIZE][/LEFT][/FONT][LEFT][/left][/SIZE][LEFT][/LEFT]
[/LEFT][/FONT][LEFT][/left][/SIZE][LEFT][/left][/SIZE][LEFT][/left][/FONT][LEFT][/left]

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Translation:

You can't fix it yourself.
In a few years when these parts are no longer available, the truck will have to be junked.

 

All I can say is WTF? seem like they're making it complicated just so they can boast how good they are at making something so complicated!!

Someone should also tell Freightliner that the thing under the bonnet that turns diesel into motion is call an engine not a motor (as in MCM), a motor is an electrical device.