1994 MAZDA MX-5 brake sensor

BRAKE SYSTEM MASTER CYLINDER (ABS) Removal / Installation / lnspection 1. Remove in the order shown in the figure, referring to Removal Note. 2. Install in the reverse order of removal, referring to Installation Note. 3. After installation, add brake fluid, bleed air, and check for fluid leakage. Caution Brake fluid will damage painted surfaces. If it does get on a painted surface, wipe it off immedi- Fluid level sensor connector 5. Proportioning bypass valve and bracket Inspection ................... page P-17 6. Master cylinder Brake pipe Installation Note ............. page P-15 Removal Note ............... page P-15 Disassembly 1 Assembly 1 Connector bolt Inspection ................. page P-18 Nut and washer Gartner Banana

BRAKE SYSTEM ADJUSTING NUT 1 2. Turn the adjusting nut until the SST body sets squarely on the master cylinder. (Turn only enough for the body to touch.) I 3. Measure and record height 02 of the gauge rod. I 4. Subtract Dl from 02 and, by using the SST, turn the nut to shorten the power booster push rod an amount equal to the sum. Inspection Fluid level sensor connector 1. Disconnect the sensor connector. 2. Connect an ohmmeter to the connector. 3. Starting with the fluid level above the MIN mark on the reservoir, verify that there is no continuity. 4. Remove the brake fluid and verify continuity when the level is below the MIN mark. 5. Replace the sensor if necessary. Gartner Banana

BRAKE SYSTEM Disassembly / Assembly / lnspection 1. After removing the brake fluid, disassemble in the order shown in the figure. 2. lnspect all parts and repair or replace as necessary. 3. Assemble in the reverse order of removal, referring to Assembly Note. Caution The brake master cylinder Is made of aluminum, and can be easily damaged by tightening in a vise. When securing the master cylinder in a vise, tighten only the master cylinder flange. 1. Fluid level sensor connector 7. Snap ring Inspection ................... page P-17 8. Snap ring and spacer (ABS) 2. Screw 9. Primarv ist ton assemblv 3. Reservoir assembly inspect for abnormal wear, rust, and damage Inspect for damage and deformation 10. Secondary piston assembly 4. Bushings Inspect for abnormal wear, rust, and damage 5. Stop screw and O-ring 11. Master cylinder body e Assembly Note .............. page P-19 Inspect for abnormal wear, rust, and damage 6. Stop pin and O-ring (ABS) Replace unit as an assembly if damaged Assembly Note .............. page P-19 Gartner Banana

P BRAKE SYSTEM Removal / Installation 1. Remove in the order shown in the figure. 2. Install in the reverse order of removal. 3. Take the following steps after installation: (1) Check and adust the push rod and piston clearance. (Standard: refer to page P-12 1 ABS: refer to page P-15.) (2) Add fluid and bleed the air. (Refer to page P-7.) (3) Check all parts for fluid leakage. (4) Check and adjust the brake pedal height and free play. (Refer to page P-9.) (5) Make an on-vehicle check of the unit. (Refer to page P-20.) (6) Check that the vacuum hose does not contact other parts. ABS 1~22 (1.3--2.2,~.&16} STANDARD 35UOPX-01 1. Fluid level sensor connector 5. Clevis tin 2. Brake pipe and proportioning bypass valve 6. Power 'brake unit 3. Master cylinder 7. Gasket 4. Vacuum hose with check valve Apply sealant to the gasket contact surface Gartner Banana

ANTILOCK BRAKE SYSTEM (ABS) P ANTILOCK BRAKE SYSTEM (ABS) DESCRIPTION - 1. There is the following distinctive characteristics in the ABS vehicles compared with the non-ABS vehicles. Note that it does not indicate malfunction. When the brakes are applied rapidly or on a slippery road surface, the ABS will activate; the brake pedal will pulsate slightly and the vehicle and the steering wheel will vibrate slightly. When the vehicle speed reaches approximately 6 kmh (3.8 mph}, the pump motor sound is heard momentarily. This sound is due to ABS self-diagnosis. 2. By retaining or reducing the hydraulic fluid pressure in the hydraulic unit, the ABS tester is used to locate the cause of a problem within the antilock brake system. Because there is no way to check the ABS control unit itself, replace the control unit assembly only after first confirming that the other electrical parts operate normally. PREPARATION SST Wrench, flare nut 49 H026 101 A Installer, sensor rotor 49 F027 007 Attachment 072 For removal and installation of brake pipe For installation of sensor rotor (rear) For removal of sensor rotor (front) 49 0839 425C Puller set, bearing Installer, oil seal Harness, adapter For removal of sensor rotor (front) For installation of sensor rotor (front) For connection of ABS tester Gartner Banana

ANTILOCK BRAKE SYSTEM (ABS) THESE THREE MESSAGES WlLL ALTERNATE ON THE DISPLAY SCREEN AT 3 112 SE- COND INTERVALS. NOW, SELECT ONE OF THE FOUR WHEELS TO BEGIN THE DY- NAMIC T EST SEQUENCE. PRESS EITHER SWITCH UN- DER "PUSH TO EXIT" DIS- PLAY TO RETURN TO "STAT TEST DYNAM" SELECTION. IMPORTANT: WHEN ENTERING THE DY- NAMIC TEST SEQUENCE, YOU WlLL SELECT ONE OF FOUR WHEELS TO BEGIN. WHEN YOU HAVE FINISHED WITH THAT WHEEL TEST. YOU SHOULD RETURN TO 6A "WHEEL SELECTION". TO SELECT ANOTHER WHEEL. AND REPEAT THESE TEST PROCEDURES FOR ALL FOUR WHEELS. 68. WHEEL SENSOR TEST NOTE: FOR EAcn OF TnE WHEEL TESTS. IT IS NECESSARY TO RAISE THE WHEEL(S) BEING TESTED OFF THE FLOOR. (WHEN TESTING REAR WHEELS. BOTH WHEELS MUST BE RAISED OFF THE FLOOR.) DISPLAY WlLL SHOW THE WHEEL WHICH YOU SELECTED IN EST 6A I HAVE YOUR ASSISTANT SPlN THE WHEEL INDICATED WHILE YOU WATCH THE TESTER. IF SPEED IS INCORRECT, TESTER WlLL DISPLAV: SPIN SLOWER I Gartner Banana

ANTILOCK BRAKE SYSTEM (ABS) P 6B. WHEEL SENSOR TEST 6C. SOLENOID TEST (Cont.) I I NOfE: EACH OFTHE TWO SOLENOID TESTS FOR EACH WHEEL CAN BE CONDUCTED FOR A MAXIMUM OF 15 SECONDS. IF TIME LIMIT IS EXCEEDED. TESTER WILL DISPLAY: I TRY TEST AGAIN I PUSH TEST 1 I PUSH EITHER SWITCH TO START THIS TEST. TESTER WILL DISPLAY: PRESS BRK.. . HOLD I APPLY FIRM PRESSURE TO BRAKE PEDAL. AND FIRMLY THROUGH SOLENOID TEST 1 AND TEST 2. I t (Cont.) Gartner Banana

ANTILOCK BRAKE SYSTEM (ABS) P ABS CONTROL UNIT 35-PIN CONNECTOR OHMMETER 15UOPX-OI Check rotor Check the rotor for missing or damaged teeth and replace as necessary. Check alternator Refer to section G. Check wheel-speed sensor Caution To prevent damage to the terminals, create a probe by wrapping a thin wire around the tester lead before inserting. 1. Using an ohmmeter, check for continuity at the control unit connector terminals. 0----0: Indicates continuity Right front Left rear Right rear 2. If the continuity is not as specified, check the wiring har- ness (Wheel-speed sensor - Control unit). 3. If the continuity is OK, check voltage between 1K and 1 G, 10 and 1 Q, 1 U and 1 F, and 1 L and 1 P while rotating the wheel one rotation per second by hand. 4. If voltage is not approximately 50 mV--60 mV, the wheel-speed sensor is faulty. 5. If voltage is approximately 50 mV-60 mV, the control unit is faulty. 1L Check hydraulics Verify that all brake fluid connections are tight and that no fluid is leaking. IP 1Q Left front 0--0 Check hydraulic unit wiring 1. Verify that the hydraulic unit connectors are properly secured. 2. Verify that the valve relay and motor relay are properly secured. IG 1K 0-4 1U 10 S-0 IF 0-4 Gartner Banana