DTC Detection Logic
With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the theoretical mixture ratio based on the mixture ratio feedback signal from the A/F sensors 1. The ECM calculates the necessary compensation to correct the offset between the actual and the theoretical ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too rich.), the ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
DTC DESCRIPTION
| Sensor | Input signal to ECM | ECM function | Actuator |
|---|---|---|---|
| A/F sensor 1 | Density of oxygen in exhaust gas (Mixture ratio feedback signal) | Fuel injection control | Fuel injector |
DTC DESCRIPTION
| DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition |
|---|---|---|
| P0172 | FUEL SYS-RICH-B1 (System too rich bank 1) |
|