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Testing with Green Lamp Function

  1. The Green lamp function on the digital code checker is used to test O2 sensor signal. Different Green light modes indicate proper or improper mixture ratios as sensed by the O2 sensor. Before testing O2 sensor, disconnect neutral switch connector. Start and run engine at idle speed. Disconnect throttle sensor connector. See Fig 1 . Digital code checker should read Code 6 with Green lamp on.
    Fig 1: Location of Throttle Sensor Connector
    G61576Courtesy of MAZDA MOTORS CORP.
  2. Increase engine speed to 2500-3000 RPM. Check that Green light starts to flash within 10 seconds after increasing engine speed. Code 6 should still be read with Green light flashing more than 8 times per 10 seconds.
  3. Maintain engine speed at 2500-3000 RPM. Disconnect O2 sensor connector. See Fig 2 . Digital code checker should read Code 5. Green lamp should be on but not flashing. If any deviation from normal, see DIGITAL CODE CHECKER CODE ILLUMINATION  chart for possible cause.
Fig 2: Location of O2 Sensor Connector
G61578Courtesy of MAZDA MOTORS CORP.
DIGITAL CODE CHECKER GREEN LAMP FUNCTIONS

Green Lamp Mode Air/Fuel Ratio
On Too Rich
Off Too Lean
Flashing Best
Fig 3: Term Locations of Cont Unit (Located Under Right Side of Dash
G50D06881Courtesy of MAZDA MOTORS CORP.
Fig 4: Code Numbers and Functions of Digital Code Checker
G50I00313Courtesy of MAZDA MOTORS CORP.
Fig 5: Control Unit Check Chart (Voltmeter)
G61580Courtesy of MAZDA MOTORS CORP.
Fig 6: Digital Code Checker Code Illumination Chart (Code 1)
G74336Courtesy of MAZDA MOTORS CORP.
Fig 7: Digital Code Checker Code Illumination Chart (Code 2)
G61582Courtesy of MAZDA MOTORS CORP.
Fig 8: Digital Code Checker Code Illumination Chart (Code 3)
G50F06882Courtesy of MAZDA MOTORS CORP.
Fig 9: Digital Code Checker Code Illumination Chart (Code 4)
G61583Courtesy of MAZDA MOTORS CORP.
Fig 10: Digital Code Checker Code Illumination Chart (Code 5)
G50H06883Courtesy of MAZDA MOTORS CORP.
Fig 11: Digital Code Checker Code Illumination Chart (Code 6)
G50J06884Courtesy of MAZDA MOTORS CORP.
Fig 12: Digital Code Checker Code Illumination Chart (Code 7)
G61585Courtesy of MAZDA MOTORS CORP.
Fig 13: Digital Code Checker Code Illumination Chart (Code 9)
G61587Courtesy of MAZDA MOTORS CORP.
Fig 14: Digital Code Checker Code Illumination Chart (Code 12)
G61589Courtesy of MAZDA MOTORS CORP.
Fig 15: Digital Code Checker Code Illumination Chart (Code 15)
G50C06885Courtesy of MAZDA MOTORS CORP.
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