Suzuki GSX-R750 Service Manual page 214

4-58 FI SYSTEM DIAGNOSIS
4) Disconnect the AP sensor coupler.
5) Turn the ignition switch ON.
6) Measure the voltage at the R wire and ground.
7) If OK, then measure the voltage at the R wire A and B/Br
wire B.
 AP sensor input voltage: 4.5 – 5.5 V
 09900-25008: Multi-circuit tester set
 Tester knob indication: Voltage ()
Is the voltage OK?
YES Go to Step 2.
• Loose or poor contacts on the ECM coupler
(terminal A or S)
NO
• Open or short circuit in the R wire or B/Br wire
Step 1 (When indicating P1450-H:)
1) Turn the ignition switch OFF.
2) Remove the front seat. (8-7)
3) Check the AP sensor coupler for loose or poor contacts.
If OK, then check the AP sensor lead wire continuity.
4) Disconnect the AP sensor coupler.
5) Check the continuity between R wire A and G/Y wire C. If
the sound is not heard from the tester, the circuit condition is
OK.
(+ R – - Ground)
(+ R – - B/Br)
1
V
1
1
!