2008 Suzuki LT-A400/F, LT-F400/F ATV Service Manual, Page 364Get this manual
4A-3 Brake Control System and Diagnosis:
Diagnostic Information and Procedures
Brake Symptom Diagnosis
Condition Insufficient brake power Possible cause Leakage of brake fluid from hydraulic systemWorn pads or liningOil adhesion on engaging surface of padsWorn disc or brake drumAir in hydraulic systemNot enough brake fluid in the reservoirDefective adjustment of rear brakeToo much play on brake pedalCarbon adhesion on pad surfaceCarbon adhesion on lining surfaceTilted padDamaged hub bearingLoosen wheel axleWorn pads and liningsForeign material in brake fluidClogged return port of master cylinderWrongly fixed springCaliper binding on caliper axleAir in hydraulic systemInsufficient brake fluidImproper quality of brake fluidInsufficient tightening of connection jointsCracked hoseWorn piston andor cupWorn piston seal and dust sealRusty partInsufficient brake lever or brake pedal pivot lubricationB827H24104001
CorrectionReference Item Repair or replaceReplaceClean disc and padsReplaceBleed airReplenishAdjustAdjustRepair surface with sandpaperRepair surface with sandpaperCorrect pad fitting or replaceReplaceTighten to specified torqueReplaceReplace brake fluidDisassemble and clean master cylinderSet correctlyClean and lubricateBleed airReplenish fluid to specified level and bleed airReplace with correct fluidTighten to specified torqueReplaceReplace piston andor cupReplace piston seal and dust sealClean and lubricateLubricate