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RecallGazette

Vehicle problems, recalls & safety intelligence

RAM 1500 2021technical service bulletin

Bulletin 0803721 · NHTSA communication 10220958 · issued Mar 16, 2021

Technical service bulletin
communication type
Electrical System
component
2021
model years
1
vehicle entries

Official summary

Flash: Hybrid Control Processor (HCP) Updates This bulletin involves updating the HCP with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs). P1A26-00 - BPCM Hybrid Battery State Of Charge Performance. P0A7E-00 - Hybrid/EV Battery Pack Over Temperature. U1003-00 - ESP Can C Bus Performance. P2534-00 - Ignition Switch Run/Start Position Circuit Low. P0506 - Idle Speed Performance Lower Than Expected. P0507 - Idle Speed Performance

Vehicles covered

What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.