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Service bulletins for the 2020 Freightliner Cascadia

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

661 on file from NHTSA, as of 2026-10-19.

By type

By component

Bulletins, newest first
TechTalk71822020-09-30. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:APPLIANCE:AIR CONDITIONER. Tech Talk discussion on New Cascadia front blower motor inoperative.
TechTalk69722020-09-30. Service bulletin. EQUIPMENT; VEHICLE SPEED CONTROL. Tech Talk discussion on P4 speedometer issues.
TechTalk66092020-09-30. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM:12V/24V/48V BATTERY; ENGINE AND ENGINE COOLING. Tech Talk discussion on Optimized Idle batteries.
TechTalk48552020-09-30. Service bulletin. ELECTRICAL SYSTEM; VISIBILITY; INTERIOR LIGHTING. Tech Talk discussion for P4 Next Gen Cascadia dome lights stay on while driving.
TechTalk47252020-09-30. Service bulletin. STEERING; EQUIPMENT. Tech Talk discussion about power steering fluid.
TechTalk45632020-09-25. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. Tech Talk discussion for P4 New Cascadia ICU display blank but gauges still work.
TechTalk39822020-09-25. Service bulletin. ELECTRICAL SYSTEM; VEHICLE SPEED CONTROL:CRUISE CONTROL. Tech Talk discussion for new cascadia w/isx cruise issue. A truck with an cummins isx with onguard, driver complains onguard cuts out and the cruise control stops working,
CTP Letter2020-09-25. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT. Customer Letter explaining for certain vehicles the software updates for the CTP will require monitoring and may affect service availability.
SS10346702020-09-24. Service bulletin. ELECTRICAL SYSTEM:IGNITION; ENGINE; EQUIPMENT. Service Solution for Fault Code VRDU 524127/9 - Lost Communication with the MPC. This Service Solution has been superseded to service bulletins SB 54-336 and 54-329. Please see the service bulletins for the most current information. VRDU fault code 524127/9 is often caused by lack of ignition supply to the MPC, which causes it to stop communicating. This usually occurs when voltage is low.
SF6072020-09-17. Service bulletin. ENGINE AND ENGINE COOLING. Field Service Campaign for Freightliner Cascadia LG1 Radiator Inlet Hoses. The radiator and upper hose assembly have an alternate design available which may extend the life of the radiator hose and prevent leaking connectors.
SB54-3362020-09-17. Service bulletin. ELECTRICAL SYSTEM. Freightliner Service Bulletin for Rewiring the MPC2 Camera Fuse. The multipurpose camera 2 (MPC2) power is supplied via fuse 14 (F14) in New Cascadia vehicles built before August 24, 2020. With this configuration, fault code 232/524127/9 - "Lost Communication to MPC" becomes active during low voltage disconnect (LVD) situations when load shedding is required to maintain critical systems. These instructions provide the procedure for moving the MPC2 power supply from fuse 14 (F14) to fuse 35 (F35). Moving the MPC2 power supply requires the installation of a new etched vehicle power distribution module (VPDM) cover to document the new MPC2 location.
CALFTL32-0072020-09-16. Service bulletin. SUSPENSION; STEERING. Customer Advisory Letter for Steer Axle Spring to Front Hanger Fastener Inspection. Our records indicate that you are the owner of certain vehicles. DTNA is requesting that the M20 fastener used to attach the steer axle spring to the forward spring hanger be inspected on these vehicles.
SS10343482020-09-16. Service bulletin. ELECTRICAL SYSTEM. Service Solution for New Cascadia Unintended 4-way Flashers Activation. As of 8/24/2020 SSAMs received an internal software change that cannot be updated in the field. The software change eliminates the unintended 4-way flasher activation issue documented in this solution. For P4 vehicles built before 8/24/2020 this solutions still applies.
SB54-3352020-09-16. Service bulletin. ELECTRICAL SYSTEM. Freightliner Service Bulletin for Optional 30K High-Current Trailer Cord Circuit Breaker Replacement. New Cascadia vehicles manufactured from September 1, 2016 through June 28, 2020 with an optional high current single- or dual-pole trailer cord were equipped with an auto-reset type I circuit breaker mounted in the battery cable access (BCA) box. Since type I circuit breakers can mask potential issues by resetting every time an over-current condition occurs, Daimler Trucks North America (DTNA) switched to a manual reset type III circuit breaker on June 29, 2020. This bulletin includes instructions for converting from a type I to a type III circuit breaker, how and where to reset a type III circuit breaker, and conditions to be aware of when troubleshooting a type III circuit breaker.
SB54-3312020-09-16. Service bulletin. VISIBILITY; EXTERIOR LIGHTING; ELECTRICAL SYSTEM. Updated Freightliner Service Bulletin for Updated ULB Control Unit for LED Headlamps. This bulletin replaces the version dated July 30, 2020. Information about a reman part has been added. New Cascadia vehicles with light emitting diode (LED) headlamps built from January 1, 2017 through February 17, 2020 may experience intermittent disabled headlamps due to an issue with the universal light ballast (ULB). The LED headlamps can turn off if the supply voltage drops below approximately 9V. This low voltage commonly and momentarily occurs when cranking the engine on a vehicle with batteries that are not fully charged. The momentary low voltage may cause the electronic ULB control unit to malfunction. The ULB may not resume normal function until the power supply to the headlamp is disconnected.
SB54-3292020-09-16. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. Updated Service Bulletin for Electrical Wall Chart and VPDM Cover on New Cascadia with Detroit Assurance 5.0 and Multi-Purpose Camera 2. This bulletin replaces the version dated 2/26/2020. Information about Service Bulletin 54-336 has been added.
SS10337002020-09-04. Service bulletin. VEHICLE SPEED CONTROL; SERVICE BRAKES. Updated Service Solution for New Cascadia Cruise Control will Not Set. Service brake state change is required to set the cruise control. Since the CPC looks to the SSAM for service brake signal the SSAM must be sending a brake signal for cruise control to function. Replaces original Service Solution from July 2018.
20CSA-152020-09-02. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; EQUIPMENT. Customer Service Announcement for Release of DiagnosticLink 8.12 Service Pack 2. On Thursday, September 3, 2020, Service Pack (SP) 2 for DiagnosticLink 8.12 Standard and Professional will be made available to download from the Detroit Diesel server.
SS10347822020-09-01. Service bulletin. EQUIPMENT. Service Solution for New Cascadia Bluetooth Microphone Relocation. Similar to Service Solution 1034680 which also informs about relocating the microphone.
SS10347622020-09-01. Service bulletin. EQUIPMENT. Service Solution for P4 Cascadia Front HVAC Evaporator Freezing. Front evaporator freezes creating ice buildup, reducing airflow through the vents. The evaporator freezing condition is very hard or cannot be duplicated, in a repair facility. Because the condition is hard to duplicate, determining root cause is still under investigation.
SS10344922020-09-01. Service bulletin. ENGINE AND ENGINE COOLING. Service Solution for New Cascadia P4 Coolant Level Wiring Damage. Fault codes can be generated if wiring to the coolant level sensor becomes damaged.
SB54-3182020-09-01. Service bulletin. ELECTRICAL SYSTEM. Service Bulletin for New Cascadia describing cab-to-chassis redundant ground strap installation to prevent damage to cab wiring. This bulletin replaces the version dated 10/29/2019. The vehicle build date has been updated.
CALFTL54-0112020-09-01. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. Customer Advisory Letter for How to program the IPPC module using DiagnosticLink.
CALFTL54-010REV2020-09-01. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; SERVICE BRAKES, AIR:ANTILOCK:ABS WARNING LIGHT; EQUIPMENT. Revised Customer Advisory Letter for New Cascadia ABS Warning Light Illumination work instructions. Due to the enhanced vigilance of the New Cascadia ABS controller, some fault codes and indicator lights do not necessarily require immediate maintenance attention. DTNA and WABCO are currently jointly working on a long-term corrective plan for the condition. REVISED: This CAL replaces the CAL issued June 17th, 2020. The phrase "if equipped" in reference to cab load disconnect switches has been removed.
CALFTL-OILHUB2020-09-01. Service bulletin. STEERING; WHEELS. Customer Advisory Letter for Visual Inspection For Oil Presence In Hub. Visual Inspection is necessary for the condition of the oil level in the steer axle hubs.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.