GLC Control Units

1984 Mazda GLC 2D HatchbackSECTION GLC Control Units
  1. The control unit may be tested with a voltmeter. Engine must be at operating temperature. For testing, ignition switch must be "ON" and engine not running. Measure voltage at each terminal and compare values to appropriate Control Unit Testing chart.
CONTROL UNIT TESTING

Terminal  Connection  Voltage  Checking Condition 
A Ignition Signal 12V Ignition switch "ON"
B Battery Power 12V Ignition switch "ON"
C A/C Signal 12V A/C "ON" (all eng. speed)
D Slow Fuel Cut Solenoid 12V At 2500 RPM w/ terminals m and o disconnected
E,I,n - - Not necessary to check
F Air/Fuel Solenoid 0-12V At idle speed
H Throttle Positioner Solenoid 12V At 1700 RPM
K EGR Solenoid 12V At 2500 RPM
M ACV Solenoid 12V At idle speed
N,p,r Ground 0V Ignition switch "ON"
a O2 Sensor 0-1V At idle speed
b O2 Sensor (Sealed) 0V Ignition switch "ON"
c Water Temperature Sensor 1.2V At idle speed
d Ground (Water Temp. Sensor) 1.2V Ignition Switch "ON"
j Power Steering 12V Power Steering "OFF"
k-l Vacuum Switch 10V Ignition switch "ON"
m Neutral & Clutch 0V At idle speed
o Idle Switch 10V At idle speed
q Water Thermo Switch 0V At idle speed
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.