FixVault

DTC Detection Logic

NOTE: DTC P1148 is displayed with DTC for A/F sensor 1.

When the DTC is detected, perform the trouble diagnosis of DTC corresponding to A/F sensor 1.

DTC No. Trouble diagnosis name (Trouble diagnosis content) DTC detecting condition Possible cause
P1148 CLOSED LOOP-B1 (Closed loop control function) The closed loop control function does not operate even when vehicle is being driven in the specified condition.
  • Harness or connectors (A/F sensor 1 circuit is open or shorted.)
  • A/F sensor 1
  • A/F sensor 1 heater