FixVault

DTC P1621: Notes

DTC P1621 [AJ] DETECTION CONDITION AND POSSIBLE CAUSES

DTC P1621 Code word does not match after engine cranking
DETECTION CONDITION 
  • Code word stored in PCM and immobilizer control module do not match
POSSIBLE CAUSE 
  • Immobilizer system reprogram procedure (code word) was not performed correctly after replacing immobilizer control module or PCM.