PR25DD engine: Notes

The specification (SP) value indicates the tolerance of the value that is displayed in "SPEC" of "DATA MONITOR" mode of CONSULT during normal operation of the Engine Control System. When the value in "SPEC" of "DATA MONITOR" mode is within the SP value, the Engine Control System is confirmed OK. When the value in "SPEC" of "DATA MONITOR" mode is NOT within the SP value, the Engine Control System may have one or more malfunctions.

The SP value is used to detect malfunctions that may affect the Engine Control System, but will not light the MIL.

The SP value will be displayed for the following three items:

• B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board correction)
• A/F ALPHA-B1 (The mean value of air-fuel ratio feedback correction factor per cycle)
• MASS AIR FLOW SENSOR (Hz) (The signal frequency of the mass air flow sensor)