Suzuki GSX-R750 Service Manual page 221

Step 1 (When indicating P1651-L:)
1) Turn the ignition switch OFF.
2) Remove the frame cover. (8-8)
3) Check the TO sensor coupler for loose or poor contacts.
If OK, then check the TO sensor lead wire continuity.
4) Disconnect the TO sensor coupler.
5) Check the continuity between B wire B and ground.
6) Also, check the continuity between B 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 R wire A and terminal A.
9) Also, then check the continuity between B wire B and termi-
nal L.
 TOS 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 2.
NO R or B wire open, or B wire shorted to ground.
10)After repairing the trouble, clear the DTC using SDS tool.
(4-27)
FI SYSTEM DIAGNOSIS
1
1
1
(Black)
ECM couplers (Harness side)
4-65
!
!
(Gray)