Mercedes Benz

P1157 Engine compartment temperature sensor P1158 Engine compartment temperature sensor Based on the provided codes, P1157 and P1158 refer to faults in the oxygen sensor and Air/Fuel (A/F) sensor circuits, not an engine compartment temperature sensor . The exact meaning depends on the make and model of the vehicle. The references to "Engine compartment temperature sensor" in your query likely caused a misinterpretation, as these P11XX codes are manufacturer-specific.   Here is what these codes typically mean for specific car makes: P1157 code For Honda:  This code indicates an issue with the Air/Fuel Ratio (A/F) Sensor 1, which is the upstream or primary oxygen sensor located in the exhaust manifold. The specific fault is a "High Voltage" reading from the sensor. For Ford:  This code, sometimes seen with P1158, can refer to a lack of switching from the HO2S22 sensor. Possible causes for Honda (P1157): A faulty A/F sensor. Damaged or corroded wiring or connectors. Ex...