B Series Truck 2WD L4-2184cc 2.2L 2200 2-bbl (1990)
Voltmeter Connection
1.
Warm up engine and run at idle.
2.
Connect a voltmeter between solenoid terminal (YR) and ground.
3.
Connect a tachometer.
4.
Increase engine speed and verify that voltmeter indicates OV above 1,400 rpm.
5.
If not, check ECU terminal 1C and water thermosensor.
Checking Vacuum Sensor
6.
Disconnect vacuum hose from vacuum sensor. Connect vacuum pump to sensor.
7.
Apply vacuum to sensor and verify that voltmeter indicates approximately 12V above 7.9 inHg (200 mmHg) vacuum.
8.
If not, verify continuity between the following components and replace ECU if necessary.
^ ECU terminal 1C and water thermosensor.
^ ECU terminal 1E and vacuum sensor.
