Jeep Grand Cherokee 2021 — technical service bulletin
Bulletin 08-317-25 · NHTSA communication 11023589 · issued Sep 23, 2025
Technical service bulletin
communication type
Electrical System
component
2021
model years
1
vehicle entries
Official summary
Flash: Amplifier (AMP) Diagnostic and System Updates **Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs):** ● B143B-12 - ANC Microphone 1-Circuit Short To Battery. ● B143C-12 - ANC Microphone 2-Circuit Short To Battery. ● B143E-12 - ANC Microphone 3-Circuit Short To Battery. ● B143F-12 - ANC Microphone 4-Circuit Short To Battery. NOTE: The DTCs are wrongly set and do not affect Active Noise Cancellation (ANC) performance. This bulletin involves updating the AMP with the latest
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.