DTC 51-xx, 52-xx, 53-xx, 54-xx, 55-xx (‘‘x'' can be 0 thru 9 or A thru F):
Internal Failure of the SRS Unit
NOTE:
Before troubleshooting any of these DTCs, check the battery/system voltage and battery cable connections. If the voltage is low, repair the charging system or replace the battery before troubleshooting the SRS. If the battery/system voltage is now OK, ask the customer if the battery ever went dead or if the engine was started and run with the battery in a low state of charge. A dead battery may trigger one or more of these DTCs.
Before replacing the SRS unit, check the SRS unit software version with the HDS. If the software version is not the latest,
update the SRS unit software
and retest.