240 L4-2320cc 2.3L SOHC VIN 83 B230FD (1993)
Checking Terminal #3
8.
Connect a lead from ECU connector pin 21 to ground.
9.
Connect voltmeter between ground and #3 connection on mass air flow sensor connector.
Reading: approx. 12 volts.
If reading is incorrect, check wiring to system relay. If wiring is O.K., check system relay (see SYSTEM RELAY).
If reading is correct, continue with next steps.
Checking Terminals #3 And #4
10.
Connect voltmeter between mass air flow sensor connection #2 (ground) and #3 (current feed from system relay).
Reading: approx. 12 volts
If reading is incorrect, repair wire from terminal #2 to ground and retest.
If reading is correct, mass air flow sensor is operating correctly.
11.
After testing, disconnect all test equipment, reconnect all connectors (including the ECU connector) and remount all panels.