BENDIX MC-12 MODULATOR CONTROLLER ASSY Troubleshooting Guide

| Compressors | Valves | Wheel End Solutions | Air Treatment | Integrated Modules | Electronics | Air Brake Handbook®

8More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Tu-Flo® 400 Compressor7.25 2 Both Both Y*Special use.e.g. Tank trailer pump-off**U

9More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Maintenance Schedule and Usage GuidelinesRegularly scheduled maintenance is the si

10More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Governors and ComponentsThe Governor monitors the air pressure in the supply rese

11More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Reservoirs and ComponentsReservoirs are available in many confi gurations. Reservo

12More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Air DryersThe air dryer is an in-line fi ltration system that removes both water v

13More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)EverFlow® ModuleThe EverFlow® air dryer module is used for air dryer systems wher

14More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Additional Charging System Related ComponentsA double check valve is used in the

15More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725) E-10PR™ BrakeValve force from the brake valve the internal return springs move b

16More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Mostly used in the transit (buses/coaches) industry, the E-10PR™ retarder contro

17More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)ActuatorsActuators Actuators convert the air pressure being applied into a mechan

©2009 Bendix Commercial Vehicle Systems LLC • All Rights Reserved

18More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Slack AdjustersSlack AdjustersThe slack adjuster is the link between a brake cham

19More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)The foundation brake is the actual braking mechanism located at each end of the a

20More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Foundation Brakes, continueda “premium” material designed for high heat situation

21More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Quick Release, Ratio ValvesQuick R elease ValvesThe function of the quick release

22More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Bobtail R atio ValvesThe LQ-5™ bobtail ratio valve is used on the front (steering

23More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Relay ValvesRelay valves are primarily used on vehicles to apply and release re

24More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Push-Pull ValvesSpring BrakesSDEEDSPP-1® Valve PP-8™ Control ValvePush-Pull Cont

25More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Spring Bra ke ValvesThe SR-1™ spring brake valve is used in dual circuit brake sy

26More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Lever Operated Control ValvesRelay Valve QR-1C® Quick Release ValveQR-1C® Quick R

27More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Additional Cont rol ValvesInversion valves are air operated control valves, and u

1More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)The Air Brake Handbook©2009 Bendix Commercial Vehicle Systems LLC • All Rights Res

28More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)SR-1™ Spring Brake ValveService Relay ValveQR-1C® Quick Release ValvePP-DC® Park

29More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)The Bendix® MV-3® dash control module is a two-button, push-pull control valve ho

30More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Tractor P rotection ValvesTractor Pr otection ValvesThe primary function of tract

31More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Trailer Spring Brake ValvesTrailer spring brake valves are designed for use in t

32More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Trailer Spring Brake Valves, continuedThe Bendix® SRC-7000™ trailer spring brake

33More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Section 5: Converter Dolly BrakesTypical components found in a converter doll

34More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725) R-8P™Relay Valve R-12P™Relay ValveTypical Converter Dolly ComponentsThe R-8P™ an

35More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Section 6: Antilock Braking SystemsFor color schematics of tractors and trucks

36More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)ABS Components continued ...• Dash-mounted tractor ABS Indicator Lamp• Service

37More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)DriverRight Steer AxleLeft Steer AxleRight Additional AxleLeft Additional AxleRig

2More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Device IndexA-18™ Controller Assy. . . . . . . 42Actuators . . . . .

38More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)For color schematics of tractors and trucks see the fold-out cover of this handbo

39More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Advanced ABS Operation, FeaturesSteering Angle SensorsThe sensor enables the Ben

40More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Stability System EffectivenessDuring high-speed maneuvers in potential rollover s

41More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Trailer ABS Components and OperationTrailer ABS ComponentsTypical Trailer ABS com

42More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)• Axle Control Mode uses a single ABS modulator to control both sides of a given

43More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)The Bendix® TABS-6 Advanced MCThe Bendix® TABS-6 Advanced MC system provides the

44More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Troubleshooting Truck, Tractor and Trailer ABSBendix ECU controllers contain self

45More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Bendix® ACom™ Diagnostics SoftwareBendix® ACom™ Diagnostics tool is a PC-based so

46More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Additional Systems and ComponentsSection 7: Additional Systems and ComponentsBen

47More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725) Bendix M odulesBeyond component and systems engineering, Bendix develops and man

3More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Handbook Section IndexHow to use the Air Brake HandbookDIN symbols are used in thi

48More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Section 8: The Fundamentals of Air BrakingFrictionAir brakes are mechanical dev

49More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)FIGURE 3 - EFFECT OF WEIGHT AND SPEED ON BRAKING FORCE REQUIRED (Note: For illust

50More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Introducing both weight and speed into the comparison again, a 10,000 pound vehic

51More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)depends on the proper location of the cam in respect to the location of the brake

52More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)second and is decelerating at the rate of ten feet per second, the stopping time

53More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)The Fundamentals of Compressed AirCompressed air is air which has been forced int

54More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)We saw earlier that normal atmospheric air is really at a pressure of 14.7 pounds

55More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)The Fundamentals of Compressed Air BrakesCompressor, Reservoir and Brake ValveIn

56More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)FIGURE 16 - BRAKING FORCES-EFFECT OF SLACK ADJUSTER ARM LENGTH Torque On Brake Ca

57More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Air Brake System BalanceThe air brake system is one of the most important safety

4More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)1. Park the vehicle on a level surface, apply the parking brakes, and always bloc

58More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)II. Mechanical SystemsGeneralVehicle manufacturers must also comply with Governm

59More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Section 9: Air Brake System Troubleshooting TestsAir Brake System Troubleshoot

60More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Air Brake System Troubleshooting Tests (continued)TEST 2 Leakage (reservoir air s

61More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Air Brake System Troubleshooting Tests (continued)TEST 4Leakage service air deliv

62More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)TEST 6Dual circuit system integrity check (emergency braking) and/or Automatic ap

63More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Downloading and Ordering Literature, Contacting BendixDownload many of these item

64More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)We supply air brake charging and control systems and components, vehicle modules,

©2009 Bendix Commercial Vehicle Systems LLC • All Rights Reserved

©2009 Bendix Commercial Vehicle Systems LLC • All Rights Reserved

©2009 Bendix Commercial Vehicle Systems LLC • All Rights Reserved

5More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Air SupplyThe vehicle’s compressor takes in fi ltered air, either at atmospheric pr

901 Cleveland Street • Elyria, OH 44035 • 1-800-AIR-BRAKE • www.bendix.comBW5057 • ©2009 Bendix Commercial Vehicle Systems LLC, a member of the

6More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)Section 2: The Charging SystemGovernorAir DryerPrimary ReservoirSafety ValveAir

7More info: visit www.bendix.com 1-800-AIR-BRAKE (1-800-247-2725)CompressorsAs the atmospheric air is compressed, all the water vapor originally in