Typical Diagnostic Reference Values
NOTE:
The footnotes are referenced throughout the Typical Diagnostic Reference Value Charts. A letter in parentheses next to a value indicates supplemental information is applicable.
The Typical Diagnostic Reference Value Charts do not display fault parameter identifications (PIDs). These are PIDs which indicate a hard fault with the circuit. They display a value of YES or NO and are PIDs ending with an F.
The Typical Diagnostic Reference Value Charts do not display limited operating strategy (LOS) PIDs. These are PIDs which indicate what LOS mode that vehicle is in. They display a value of YES or NO.
Reference values may vary 20% depending on operating conditions, altitude, and other factors. The RPM values are axle and tire dependent.
Values are taken at an altitude of approximately 189 meters (620 ft) above sea level with the engine at normal operating temperature and accessories off.
For the downstream heated exhaust gas oxygen sensor (HO2S12), greater activity results when the catalyst monitor is active.
Refer to the Introduction in, ACRONYMS AND DEFINITIONS for technical terms applicable to Ford Motor Company products.
Refer to PARAMETER IDENTIFICATION (PID) , for PID descriptions.
The Typical Diagnostic Reference Value Charts do not display fault parameter identifications (PIDs). These are PIDs which indicate a hard fault with the circuit. They display a value of YES or NO and are PIDs ending with an F.
The Typical Diagnostic Reference Value Charts do not display limited operating strategy (LOS) PIDs. These are PIDs which indicate what LOS mode that vehicle is in. They display a value of YES or NO.
Reference values may vary 20% depending on operating conditions, altitude, and other factors. The RPM values are axle and tire dependent.
Values are taken at an altitude of approximately 189 meters (620 ft) above sea level with the engine at normal operating temperature and accessories off.
For the downstream heated exhaust gas oxygen sensor (HO2S12), greater activity results when the catalyst monitor is active.
Refer to the Introduction in, ACRONYMS AND DEFINITIONS for technical terms applicable to Ford Motor Company products.
Refer to PARAMETER IDENTIFICATION (PID) , for PID descriptions.
- Heated oxygen sensors (HO2S) should switch from rich to lean at least once every 3 seconds. HO2S voltage should toggle above and below 0.450 DCV and never be a negative value. Valid HO2S switching occurs only during closed loop fuel control operation.
- Downstream oxygen sensors stay close to a constant voltage when the catalyst monitor is off (positive value only). When the catalyst monitor is on, the HO2S switches from rich to lean above and below 0.450 DCV and should never be a negative value. For downstream oxygen sensors (12, 22) greater activity results when the catalyst monitor is active.
- Value is not useful under this condition.