Test Point 8 - Oxygen sensor regulation/stop
TEST POINT 8 - Oxygen regulation stop - Fault code 1_23Possible Causes, Elimination, Remarks
The oxygen regulator cannot operate within its control range if extreme problems of mixture preparation occur, e.g. due to an excessively lean setting because of unmetered air, or due to an excessively rich setting because of a faulty injector valve. The oxygen regulator then moves up to the stop position.
Oxygen regulation too rich:
^ Check intake system for leaks
Oxygen regulation too lean:
^ Check fuel pressure
^ Check injector valves for leaks
Oxygen sensor Short to +/short to ground - Fault code 1_24
Possible Causes, Elimination, Remarks
If the control unit detects an oxygen sensor voltage signal of more than 1.4 V or less than 0.1 V, the control unit switches to operation without oxygen sensor. (Short to ground or open circuit).
If regulation does not work and the sensor voltage is O.K., use System Tester 9288 to check the coding of the control unit before replacing it.