35
8. Operate Sensor.
Start engine and let idle.
Display reading should...
increase in voltage from Key On
Engine OFF for DC type MAF sensors.
increase in RPM from Key On Engine
OFF for Low Frequency type MAF
sensors.
Rev Engine.
Display reading should...
increase in voltage from Idle for DC
type MAF sensors.
increase in RPM from Idle for Low
Frequency type MAF sensors.
Refer to vehicle service manual for
charts relating MAF sensor voltage or
frequency(RPM) to increasing air flow.
Use equation above for Frequency and
RPM conversions.
9. Test Results.
Good Sensor:
Sensor output voltage or frequency
(RPM) are within manufacturers
specifications at Key ON Engine OFF.
Sensor output voltage or frequency
(RPM) increase with increasing air flow.
Bad Sensor:
Sensor output voltage or frequency
(RPM) are not within manufacturers
specifications at Key ON Engine OFF.
Sensor output voltage or frequency
(RPM) do not change with increasing air
flow.
Electrical Specifications
DC Volts
Range: 2V, 20V, 200V
Accuracy : ±(1.0% rdg + 2 dgts)
AC Volts
Range: 750V
Accuracy: ±(0.75% rdg + 2 dgts)
Resistance
Range:
200
Ω
, 2K
Ω
, 20K
Ω
, 200K
Ω
, 2M
Ω
, 20M
Ω
Accuracy: ±(0.75% rdg + 2 dgts)
Dwell
Range: 4CYL, 5CYL, 6CYL, 8CYL
Accuracy: ±(3.0% rdg + 5 dgts)
RPM
Range: 4CYL, 5CYL, 6CYL, 8CYL
Accuracy: ±(3.0% rdg + 5 dgts)
