2009 Suzuki 400 LTZ Quad Sport Service Manual, Page 99Get this manual
1A-35 Engine General Information and Diagnosis: C15 (Use of mode select switch) Step Action 1) Turn the ignition switch OFF2) Check the ECT sensor coupler for loose or poor contactsIf OK, then measure the ECT sensor voltage at the wire side couplerYes Go to Step 2No Loose or poor contacts on the ECM coupler Open or short circuit in the BBl or BBr wire I933H1110039-01
3) Disconnect the coupler and turn the ignition switch ON4) Measure the voltage between the BBl wire terminal and groundIf OK, then measure the input voltage between BBl wire terminal and BBr wire terminalSpecial tool (A): 0990025008 (Multi-circuit tester set) (B): 0990025009 (Needle pointed probe set) Tester knob indication Voltage) ECT sensor voltage 4.5 5.5 ((+) terminal: BBl () terminal: Ground, (+) terminal: BBl () terminal: BBr)