Technical Service Bulletin SSM 51170 — 2021 FORD F-450 SD
ENGINE AND ENGINE COOLING
Bulletin Details
| TSB ID | SSM 51170 |
| Manufacturer | |
| Vehicle | 2021 FORD F-450 SD |
| Component | ENGINE AND ENGINE COOLING |
| Communication Date |
Bulletin Summary
Some 2020-2022 F-Super Duty vehicles equipped with a 6.7L engine may exhibit an A/C system blowing only warm air. This may be due to the powertrain control module inhibiting the engagement of the air conditioning compressor clutch with parameter identification (PID) AC_INHIBIT_11 status showing TRUE. If this PID shows TRUE but the ambient air temperature PID reads correctly, this may be due to a disconnected mass air flow sensor with the ignition on, especially after checking the condition of the engine air filter. To correct the condition, clear all diagnostic trouble codes and perform the HVAC or FCIM - Reset the Outside Air Temperature Sensor Learned Values application. If the condition remains, the vehicle needs to be driven for 2-5 minutes over 23 mph (37 km/h). If the condition still remains, refer to Workshop Manual, Section 412-00 for normal diagnostics.
About Technical Service Bulletins
A Technical Service Bulletin (TSB) is a document issued by a vehicle manufacturer to its dealers, describing a known issue with a specific vehicle or set of vehicles and the recommended procedure to fix it. Unlike recalls, TSBs are not mandatory and are typically only performed if an owner reports the related issue. However, TSBs can be an indicator of common problems with a vehicle.