Suzuki GSX-R750 Service Manual page 228

4-72 FI SYSTEM DIAGNOSIS
Step 1 (When indicating P1654-L:)
1) Turn the ignition switch OFF.
2) Lift and support the fuel tank. (5-3)
3) Check the STP sensor coupler for loose or poor contacts.
If OK, then check the STP sensor lead wire continuity.
4) Disconnect the STP sensor coupler.
5) Check the continuity between Y/W wire B and ground.
6) Also, check the continuity between Y/W wire B and B/Br wire
C. If the sound is not heard from the tester, the circuit condi-
tion is OK.
7) Disconnect the ECM coupler.
8) Check the continuity between Y/W wire B and terminal J.
9) Also, check the continuity between R wire A and terminal A.
 STPS lead wire continuity: Continuity ()
 09900-25008: Multi-circuit tester set
09900-25009: Needle pointed probe set
 Tester knob indication: Continuity test ()

When using the multi-circuit tester, do not storongly
touch the terminal of the ECM coupler with a needle
pointed tester probe to prevent the terminal damage
or terminal bend.
Is the continuity OK?
YES Go to Step 1 (4-70) and go to Step 2.
R or Y/W wire open, or Y/W wire shorted to
NO
ground
10)After repairing the trouble, clear the DTC using SDS tool.
(4-27)
1
1
1
(Black)
ECM couplers (Harness side)
!
(Gray)