Diagnostic Rules

  • A cleared check engine light leaves internal I/M Readiness monitors in an 'Incomplete' or 'Not Ready' state.
  • If EVAP, Catalyst, or O2 monitors show 'Not Ready', assume a fault code was cleared within the last 15 miles.
  • Carry a handheld bidirectional OBD-II scanner capable of reading permanent (non-clearable) DTCs.

Disreputable sellers frequently clear trouble codes 20 minutes before driving a car onto the auction block. Knowing how to read internal ECU readiness monitors protects your wallet from expensive catalytic converter replacements.

"El acceso directo a subastas de concesionario permite a los operadores independientes adquirir inventario entre un 15% y 30% por debajo del precio minorista, eliminando márgenes de intermediarios."