Test Description

The numbers below refer to the step numbers on the diagnostic procedures.

1. 1
   
   The Diagnostic System Check - Engine Controls prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. 2
   
   This step checks for a high input signal from MAF sensor.
3. 3
   
   This step checks for a low input signal from MAF sensor.
4. 5
   
   The MAF sensor has 5 test terminals that are easily reached when MAF sensor is not attached to air cleaner housing. The test terminals enable the technician to measure the circuit voltages of MAF sensor with all components connected.
5. 6
   
   This step is looking for MAF sensor output on the MAF signal high circuit. Air movement around the sensor's hot wire element can cause some fluctuation in the voltage being measured.