900 L4-1985cc 2.0L DOHC Turbo EFI (1985)
Throttle Position Switch: Testing and Inspection
1.
Disconnect electrical connector from ECU and remove cover.
2.
Connect a suitable ohmmeter between ECU terminals 3 and 11. Ensure circuit is closed. If circuit is open, check gray wire between connector
terminal 3 and throttle switch. Also check black wire between connector terminal 11 and ground, then the black wire between throttle switch and
ground.
3.
Move throttle valve and check ohmmeter readings. If the switch is operating properly, the circuit should be broken immediately after the throttle
valve is moved from its idle position. If not, check position of throttle valve as follows:
a. Loosen attaching nut and adjusting screw.
b. Turn adjusting screw until screw touches throttle valve stop.
c. Turn adjusting screw an additional 1/3 of a turn and lock with nut.
d. To adjust throttle switch, loosen throttle housing attaching screws.
e. Rotate switch assembly until switch touches idle position integral stop.
f.
Tighten throttle housing attaching screws.
4.
Connect ohmmeter to ECU connector terminals 3 and 11. Ensure circuit is broken when the throttle valve is moved from the idle position.
5.
Connect ohmmeter between terminals 11 and 12. If the switch is operating properly, the circuit should be closed when the throttle valve is moved
to the full throttle position (approximately 72°). If the circuit is not closed, check green/red wire between ECU terminal 12 and throttle switch
terminal 3, black wire between ECU terminal 11 and ground, and the black wire between the throttle switch and ground.
6.
If the wires are properly connected and/or no damage is detected and the switch still fails to operate correctly, replace throttle switch assembly.