Conditions

Closed Loop







Fault symptoms
CHECK ENGINE lamp on. Possible other diagnostic trouble codes (low fuel level, misfiring, oxygen sensor, pressure sensor)

Conditions
- Global adaptation performed during the driving cycle
- Closed loop active.

P1171: Closed loop >25% for longer than 20 sec.
P1172: Closed loop <-25 % for longer than 20 sec.

Diagnostic help
If the closed loop fault is due to low fuel level, this will be indicated by diagnostic trouble code P1416 also being generated. Closed loop can be read with the diagnostic tool.
- Select "READ FUNCTIONS".
- Select "SHORT TERM FUEL TRIM".

Current closed loop ±25% is shown.

Checking the wiring harness. Intermittent faults may occur in connection with short circuits and open circuits. Jiggle the wiring harness at several points and in several directions to locate any problems in the wiring, including intermediate connectors. Observe the multimeter, scan tool or test lamp during the check.