NHTSA ID Number: 10189331
Manufacturer Communication Number: SB54-338
TSB/Document Date: 2021-03-24
Summary
Revised Freightliner
Service Bulletin for Updating HVAC ECU Software to Fix Front HVAC Evaporator Freezing and Improve Espar Heater Cool Down. This bulletin replaces the version dated 12/23/2020. Information has been added about ParkSmart units and the instructions have been streamlined.
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
54-338
Freightliner
Service Bulletin
Description of Revisions: This bulletin replaces the version dated
12/23/2020. Information has been added about ParkSmart units
and the instructions have been streamlined.
General Information
New Cascadia vehicles with sleeper cabs may become extremely cold when in A/C mode, which can lead to
reduced airflow as a result of internal ice buildup at the evaporator.
Conditions that contribute to the front evaporator freezing include:
• Engine at 900 rpm and above, typically noticed when vehicle is moving at 60 mph (97 km/h) or more.
• Air conditioning in recirculation mode; the front evaporator may freeze in ECO mode but it will take much
longer.
• Blower motor operating at 50% power or above.
• Temperature control knob turned to the full cold setting.
• Ambient temperature approximately 86°F (30°C) or above.
• Humidity at 75% or higher.
There are also issues with the durability of the Espar D5 heater system when paired with the battery parked
HVAC system (BPHS). This can be improved by applying "cool down" software to the parked ECU
(HVAC_P01T).
The front evaporator freezing issue is addressed by the new software available for the front ECU (HVAC_F01T)
and auxiliary ECU (HVAC_R01T).
This software is now available and should be installed. The software is backwards compatible for all ECUs.
Each vehicle will require software updates to two ECUs.
For vehicles without a Battery Powered HVAC System (BPHS), software includes:
• HVAC_F01T software 001 448 14 28 version 001 or newer.
• HVAC_R01T software 001 448 07 28 version 001 or newer.
For vehicles with a BPHS unit, use the following software:
• HVAC_F01T software 001 448 14 28 version 001 or newer.
• HVAC_P01T software 000 448 70 28 version 007 or newer.
For vehicles with a ParkSmart unit, use the following software:
• HVAC_F01T software 001 448 14 28 version 001 or newer.
• HVAC_P01T software 000 448 68 28 version 003 or newer.
After the HVAC_F01T and HVAC_P01T software has been updated, drivers may notice the fan running for
approximately three minutes after the Espar D5 heater has turned off.
General Information
There are two different procedures for programming chassis ECUs with DiagnosticLink:
• Updating functioning vehicle chassis ECUs by uploading the parameters of the vehicle’s ECUs to the
server and then downloading these parameters with the updated software.
Freightliner Service Bulletin, 03/03/2021
Page 1
54-338
Freightliner
Service Bulletin
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
• Overwriting the parameters and software installed on the ECU with the most recent parameter sets and
software from the server by directly using ’Program Device.’
This service bulletin will use the second procedure to program the HVAC_F01T ECU and either the
HVAC_R01T ECU or HVAC_P01T ECU.
Procedure
1. Park the vehicle on a level surface, shut down the engine, and apply the parking brakes. Chock the tires.
2. Connect the vehicle to DiagnosticLink. Ensure DiagnosticLink is updated to the latest version (8.13 at the
time of publication) or newer. To update DiagnosticLink, select ’Tools’ from the top menu and then select
’Update’ from the dropdown menu. See Fig. 1.
01/15/2021
f120507
Fig. 1, Updating DiagnosticLink to the Latest Version
2.1
When programming, we recommend configuring DiagnosticLink to connect only to ’Default’ ECUs.
To make this change in DiagnosticLink:
• Select ’Tools’ from the top menu, and then select ’Options’ from the drop down menu.
• Find and select the ’Connection’ tab. See Fig. 2.
• Select the ’Select Defaults’ button on the right side of the window, then select ’Apply.’
Page 2
Freightliner Service Bulletin, 03/03/2021
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
54-338
Freightliner
Service Bulletin
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
1
2
3
02/01/2021
f120850
1. ’Connection’ Tab
2. ’Select Defaults’ Button
3. ’Apply’ Button
Fig. 2, Configuring DiagnosticLink to Connect to Default ECUs
3. Address any pre-existing conditions or fault codes.
NOTE: In DiagnosticLink an ECU is called a ’device.’
4. Select ’Program Device’ from the upper left-hand side of the window. See Fig. 3.
02/01/2021
f120466a
Fig. 3, Selecting Program Device (ECU)
Freightliner Service Bulletin, 03/03/2021
Page 3
54-338
Freightliner
Service Bulletin
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
5. Remove any ’Request Pending’ downloads and serial numbers in the main window by selecting the
’Request Pending’ list item(s) and then selecting the ’Remove’ button on the right-hand side of the window.
Do not select ’Remove All;’ selecting ’Remove All’ deletes all data pending upload. See Fig. 4.
02/04/2021
f120463a
Fig. 4, Removing Pending Requests
6. Use your DTNAConnect information to connect to the server. Your sign-in to the server will remain active
until DiagnosticLink is closed.
7. Select ’Add’ to add a download request for the vehicle by entering the vehicle identification number (VIN).
See Fig. 5.
01/15/2021
f120841
Fig. 5, Adding the VIN to Download Updated Server Data
8. Make sure the correct VIN is populated in the window, then select ’OK.’ See Fig. 6.
Page 4
Freightliner Service Bulletin, 03/03/2021
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
Freightliner
Service Bulletin
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
01/14/2021
54-338
f120842
Fig. 6, Verifying VIN
9. There should be a request pending status for the VIN. Select ’Connect to Server’ as shown in Fig. 7, to
download the updated software for the vehicle’s ECU(s).
The server will provide all new software available for this vehicle’s default ECUs.
Freightliner Service Bulletin, 03/03/2021
Page 5
54-338
Freightliner
Service Bulletin
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
01/15/2021
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
f120843
Fig. 7, Downloading Updated Vehicle ECU Software
10. Once the data has been downloaded, select ’Next.’ See Fig. 8.
Page 6
Freightliner Service Bulletin, 03/03/2021
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
01/15/2021
54-338
Freightliner
Service Bulletin
f120844
Fig. 8, Selecting Next
NOTE: ’Latest’ is the last service record (may be older software) and ’Newest’ is the most up to date
software available for the installed hardware. If the last service record is the most up to date software
available, no ’Newest’ record will be provided.
11. Select either the HVAC_F01T ECU, HVAC_R01T ECU, or HVAC_P01T ECU to program, select the VIN,
and select ’Newest’ if available.
If ’Newest’ is not available, the selected ECU has the most up to date software. If this is the case, select
the second ECU to program, select the VIN, and select ’Newest.’
Select ’Next.’ See Fig. 9
Freightliner Service Bulletin, 03/03/2021
Page 7
54-338
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
Freightliner
Service Bulletin
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
1
2
3
4
03/01/2021
f120861
1. Device to Program
2. HVAC_FO1T Device (ECU)
Selected
2. Vehicle Identification Number
(VIN)
3. Settings With ’Newest’ Software
Selected
Fig. 9, Selecting ECU to Program, VIN, Software Version
12. If the ECU currently installed has a different part number than what is stored on the server, the pop-up note
shown in Fig. 10 may appear. If this happens, select OK and continue to the next step.
03/01/2021
f120863
Fig. 10, Device (ECU) a Different Part Number Pop-Up
13. Review and verify the ECU selected, the software version being installed (’Target’ software number)1, and
the hardware part number. See Fig. 11. Then select ’Start’ to program the ECU.
The software will be downloaded and written to the selected ECU.
1 This version number should be the number listed in the General Information section or newer.
Page 8
Freightliner Service Bulletin, 03/03/2021
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
54-338
Freightliner
Service Bulletin
1
2
3
4
03/01/2021
f120862
1. Device (ECU) to be Programmed
2. Software Version
3. Hardware Part Number
4. Start Button
Fig. 11, Programming the ECU
14. When programming is complete, the page will display the message ’The device was successfully
programmed.’ Select ’Finish.’
NOTE: Both the HVAC_F01T ECU and the HVAC_R01T ECU or HVAC_P01T ECU need to be
updated. Make sure to complete both required updates for the vehicle. To update the second module,
select the VIN number on the main screen and return to step 11.
15. After the programming is finished, select ’Connect to server’ to complete the software update process.
IMPORTANT: After a programming, some fault codes may become active and some ECUs may not
auto-connect. Cycling the ignition may clear the faults and connect the ECUs.
16. Turn the ignition to the OFF position, unplug from the diagnostic port and close and restart DiagnosticLink.
Wait one minute.
16.1
Cycle the ignition three times, waiting 30 seconds between key OFF and key ON.
NOTE: This action will enable Intelligent Predictive Powertrain Control (IPPC) to start
communicating on Roll Call, and eliminate codes for the IPPC not communicating.
16.2
Turn the key to the ON position for the fourth time and connect the vehicle to DiagnosticLink.
17. Clear inactive faults and troubleshoot any active faults.
17.1
If the ICUC configuration fault is active (SPN 523023 FMI 31), select the ’Actions’ menu and scroll
down and select ’Instrument Cluster Automatic Configuration.’
Freightliner Service Bulletin, 03/03/2021
Page 9
54-338
Freightliner
Service Bulletin
17.2
Updating HVAC ECU Software to Fix Front HVAC
Evaporator Freezing and Improve Espar Heater Cool Down
FLA COE
FLB COE
FLD Conventional
Business Class
FLC 112 Conventional
Century Class Conventional
Argosy
Cargo
Columbia
122SD and Coronado
Business Class M2
Cascadia
108SD/114SD
> New Cascadia
Verify that the menu selection at the bottom of the window is ’Auto-config ECU List’ and select
’Start.’
18. When the programming of both HVAC ECUs has been updated, and if required, the ICU has been
configured, turn the ignition to the OFF position, unplug from the diagnostic port, and close DiagnosticLink.
Warranty
This procedure is warrantable only if the described condition exists and the repair is performed within the
applicable base or extended coverage warranty period. If a failure is not found, this procedure is considered
preventive and warranty does not apply.
Normal warranty applies. See Table 1 for OWL VMRS codes and labor allowance information. Enter this service
bulletin number in the Service Bulletin # field.
Primary Failed Part
HVAC Controller
OWL VMRS Codes and Labor Allowance
Component
Cause Code SRT Code
Description
Code
HVAC CONTROLLERS, FCU AND ACU
001-001-261
93
703-5009A OR PCU PROGRAMMING, UPDATE
PER INSTRUCTIONS (SB 54-338)
Time: Hours
0.7hrs
Table 1, OWL VMRS Codes and Labor Allowance
Page 10
Freightliner Service Bulletin, 03/03/2021
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