Suzuki Intruder VZR1800 Service Manual page 249

Step 1 (When indicating P1651-H:)
1) Turn the ignition switch OFF.
2) Remove the fuel tank. (#6-3)
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 Red wire A and Black wire B.
If the sound is not heard from the tester, the circuit condition is
OK.
6) Disconnect the ECM coupler. (#5-37)
7) Check the continuity between Black wire B and terminal L.
8) Also, check the continuity between B/Br wire C and terminal S.
"
When using the multi-circuit tester, do not strongly
touch the terminal of the ECM coupler with a needle
pointed tester probe to prevent the terminal damage
or terminal bend.
$ TOS lead wire continuity: Continuity (()
! 09900-25008: Multi-circuit tester set
09900-25009: Needle pointed probe set
) Tester knob indication: Continuity test (()
Is the continuity OK?
YES Go to Step 2.
NO Black wire shorted to VCC, or B/Br wire open.
9) After repairing the trouble, clear the DTC using SDS tool.
(#5-26)
FI SYSTEM DIAGNOSIS
1
1
1
(Black)
ECM coupler (Harness side)
5-55
(Gray)