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Service bulletins for the 2020 Ram 4500

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.

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

By type

By component

By trouble code

Only bulletins with component: Heating and air conditioning are shown. Show all

Bulletins, newest first
23080232023-08-21. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM. Intermittently Poor HVAC Performance Customers may comment on the following: ? Intermittently the HVAC blow feel/output maybe reduced. This issue only happens in temperature that are just below freezing and snowing. This bulletin involves removing the right side rubber flaps from the cowl baffles.
S22230000632022-11-07. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM; ELECTRICAL SYSTEM:BODY CONTROL MODULE/BCM. Ambient Temperature Sensor Servicing.
08101202022-10-17. Service bulletin. EQUIPMENT:APPLIANCE:AIR CONDITIONER. Heating, Ventilation and Air Conditioning (HVAC) Controls Inoperative This bulletin involves replacing the HVAC module. Customers may experience not being able to change the HVAC modes, both on the radios display or HVAC controls.
S21240000032022-09-26. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM. A/C Performance Not As Hot/Cold On Driver Side - DTC's B11CB-92, B11CB-11
S19240000192022-09-26. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM. Customer Indicates That Temperature Varies From Side To Side Being Colder On One Side Compared To The Other.
S1924000019RevB2022-09-26. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM. Customer Indicates That Temperature Varies From Side To Side Being Colder On One Side Compared To The Other.
S21240000042022-09-26. Service bulletin. EQUIPMENT:APPLIANCE:AIR CONDITIONER; VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM. A/C does not cool and vehicle is low on Freon charge but no leak is found with sniffer or black light anywhere in the system
24-001-202020-12-28. Service bulletin. EQUIPMENT:APPLIANCE:AIR CONDITIONER. HVAC Housing Service This bulletin informing the Technician about an HVAC housing redesign with components that need to be serviced together when servicing the HVAC housing. Customers may experience the following: Poor Air conditioning system performance (Slow or excess time to cool down). HVAC is slow to cool, left center instrument panel outlet is warmer than right side instrument panel outlets.
08-101-202020-12-28. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM:HEATER CORE; ELECTRICAL SYSTEM. Heating, Ventilation and Air Conditioning (HVAC) Controls Inoperative This bulletin involves replacing the HVAC module. Customers may experience not being able to change the HVAC modes, both on the radios display or HVAC controls.
24-001-202020-12-21. Service bulletin. EQUIPMENT:APPLIANCE:AIR CONDITIONER; EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT. HVAC Housing Service This bulletin informing the Technician about an HVAC housing redesign with components that need to be serviced together when servicing the HVAC housing. Customers may experience the following: Poor Air conditioning system performance (Slow or excess time to cool down). HVAC is slow to cool, left center instrument panel outlet is warmer than right side instrument panel outlets.
08-101-202020-12-21. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:APPLIANCE:AIR CONDITIONER. Heating, Ventilation and Air Conditioning (HVAC) Controls Inoperative This bulletin involves replacing the HVAC module. Customers may experience not being able to change the HVAC modes, both on the radios display or HVAC controls.

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