1994 MAZDA MX-5 steering

CONTROL SYSTEM STRUCTURAL VIEW i 1. Powertrain control module (engine) 6. Heated oxygen sensor Inspection . . . . . . . . . . . . . . . . . . page F-144 Inspection . . . . . . . . . . . . . . . . . . page F-156 Removal / Installation . . . . . . . . page F-143 Replacement . . . . . . . . . . . . . . . page F-156 2. Crankshaft position sensor 7. Main relay Removal . . . . . . . . . . . . . . . . . . . page F-153 Inspection . . . . . . . . . . . . . . . . . . page F-156 lnspection . . . . . . . . . . . . . . . . . . page F-153 8. Clutch switch Installation . . . . . . . . . . . . . . . . . page F-153 Inspection . . . . . . . . . . . . . . . . . . page F-157 3. Mass airflow sensor Replacement . . . . . . . . . . . . . . . page F-157 System inspection . . . . . . . . . . . page F-152 9. Neutral switch Inspection . . . . . . . . . . . . . . . . . . page F-152 Inspection . , . . . . . . . . . . . . . . . . page F-157 4. Engine coolant temperature sensor Replacement . . . . . . . . . . . . . . . page F-157 Removal . . . . . . . . . . . . . . . . . . . page F-154 10. Steering pressure sensor Inspection . . . . . . . . . . . . . . . . . . page F-154 Inspection . . . . . . . . . . . . . . . . . . page F-158 Installation . . . , . . . . . . . . . . . . . page F-154 Replacement . . . . . . . . . . . . . . . page F-158 5. Throttle position sensor -,' Inspection . . . . . . . . . . . . . . . . . . page F-155 Adjustment . . . . . . . . . . . . . . . . . page F-155 Replacement . . . . . . . . . . . . . . . page F-156 Gartner Banana

CONTROL SYSTEM F Terminal voltage B+: Battery positive voltage Test condition I Voltage I Remark - - - - - - - - - - - - - - - - - - Connection to Battery Constant Ignition switch OFF Main relay - B+ OV lgnition switch (Start position) For backup - Ignition switch ON While cranking Lamp illuminated for 3 sec. after 1 4.5-5.5V ianition switch OFF+ON 1 B+ Approx. 1 OV Ignition switch ON - - OV Data link connector (MEN terminal) Test switch at "SELF-TEST" .. Lamp not illuminated after 3 sec. Test switch at "02 MONITOR" at idle Monitor lam illuminated & 4.5-5.5v . . I Malfunction indicator IighVData link connector (FEN ter- minal) With Self-Diagnosis Checker and System Selector Test switch at "02 MONITOR" at idle Monitor lamp not illuminated Light illuminated and buzzer sounded for 3 sec. after ignition switch OFF-ON B+ tor tesiswitch at "SELF-TEST" With Self-Diagnosis checker and system selector Below 2.5V 1 Light illuminated and buzzer sounded 1 Below 2.5V I With System Selec- Light not illuminated and buzzer not sounded after 3 sec. I Light not illuminated and buzzer 1 n. 1 B+ not sound I D+ 1 - #I, 4 lgniter (in IG COIL) #2,3 Igniter (in IG COIL) Powertrain control module (transmis- sion) - Ignition switch ON Idle Ignition switch ON Idle lgnition switch ON (Engine coolant temp, below 60°C {I 40°F)) Ignition switch ON AtC relay Air conditioning sensor ON at idle Air conditioning sensor OFF at idle Ground (MT) - OV Approx. 0.2V OV Approx. 0.2V Below 1 .OV B+ Below 2.5V B+ - - - - , * Open (AT) - Ignition switch ON ( Below 1 .O V I Engine coolant temp. I Below .OV I ldle Above 97°C (206.6OF1 Ignition switch ON I I B+ Ignition switch ON Coolant fan relay B+ . - Other conditions lgnition switch On dround data link connector TEN terminal I Blow 1.0" I B+ Vehicle speed sensor ldle switch OFF While driving Vehicle sto~wed ldle switch (in throttle position sensor) 2-5V 1 or 7V . , Accelerator pedal released Accelerator ~edal de~ressed - Stoplight switch OV B+ Brake pedal released Brake ~edal deoressed lgnition switch ON Steering pressure sensor OV B+ I I - Ignition switch ON B+ - PIS ON (at idle) PIS OFF (at idle) Air conditioning sensor Air conditioning sensor ON (Igni- tion switch ON) Air conditioning sensor OFF (Igni- tion switch ON) OV B+ - Below 2.5V B+ Blower motor ON Gartner Banana

CONTROL SYSTEM B+: Battery positive voltage Terminal 1 M 7 1 N 10 1 P 1 Q 1 R 1 S 1 T 1 U Connection to Abnormal voltage Always approx. 1 V Always approx. 7V Possible cause r Vehicle speed sensor malfunction r Short circuit in wiring from vehicle speed sensor to PCME terminal 1 M Vehicle speed sensor - r Vehicle speed senso~malfunction r Open circuit in wiring from vehicle speed sensor to PCME terminal 1 M r Throttle position sensor misadjustment (Refer to page F-154) r Short circuit in wiring from PCME terminal 1 N to throttle position sensor 6 PCME malfunction Always OV Throttle position sensor (idle terminal) Always B+ r Throttle position sensor misadjustment (Refer to page F-154) r Open circuit in wiring from PCME terminal 1 N to throttle position sensor r Open circuit in wiring from throttle position sensor to ground Stoplight switch Always OV (Stoplights OK) r Open circuit in wiring from stoplight switch to PCME terminal 10 r Steering pressure sensor malfunction (Refer to page F-158) Short circuit in wiring from PCME terminal 1 P to steering pressure sensor r PCME malfunction r Steering pressure sensor malfunction (Refer to F-158) r Open circuit in wiring from PCME terminal 1 P to steering pressure sensor Open circuit in wiring from steering pressure sensor to ground r Air conditioning sensor malfunction (Refer to section U) r Short circuit in wiring from PCME terminal 1 Q to air conditioning sensor r Poor connection at PCME connector r PCME malfunction Always OV Steering pressure sensor Always B+ -- Air conditioning sensor Always OV (with blower switch ON) Air conditioning sensor malfunction (Refer to section U) Open circuit in wiring from PCME terminal 1Q to air conditioning sensor Open circuit in wiring from air conditioning sensor to blower switch Always B+ (with blower switch ON) (Blower fan OK) EGR solenoid valve (vent) Always OV r Refer to Code No.29 Troubleshooting (Refer to page F-92) Short circuit in wiring from blower switch to PCME terminal 1 S r Poor connection at PCME connector PCME malfunction Always OV (Blower fan OK) Blower switch Always B+ (Blower fan OK) Open circuit in wiring from blower switch to PCME terminal IS EGR solenoid (vacu- um) Always OV r Refer to Code No.28 Troubleshooting (Refer to paae F-92) Headlight switch Always OV (Headlights OK) r Open or short circuit in wiring from headlight relay to PCME terminal 1 U Gartner Banana

CONTROL SYSTEM Replacement Replace the neutral switch as shown in the figure. STEERING PRESSURE SENSOR Inspection 1. Disconnect the steering pressure sensor connector. 2. Connect an ohmmeter to the switch. 3. Start the engine and let it idle. Check continuity of the switch while turning the steering wheel. PIS 1 Continuity Turnina Yes " I t ~ot turning I NO 4. If not as specified, replace the steering pressure sensor. Replacement Replace the steering pressure sensor as shown in the figure. Gartner Banana

CHARGING SYSTEM B TE S TERMINAL 1. Remove the battery cover. 2. Disconnect the battery cable from the battery. 3. Remove the battery from the vehicle. 4. Place the battery in a pan of the water to prevent it from ,-, over heating, but keep water away from the top of bat- tery. 5. Charge the battery. Replacement Note When replacing the battery, replace it with the same style Mazda genuine battery (with vent manifold). ALTERNATOR Caution Obtain the code number and deactivate the audio anti-theft system before disconnecting the bat- tery. (Refer to section T.) Caution Reversing the battery connections or using high- voltage testers will damage the rectifier. Caution Do not start the engine while the connector is dis- connected from L and S terminals. It can damage the alternator. Note .--,' Positive voltage is always present at alternator B ter- minal. Removal l Installation 1. Disconnect the negative battery cable. 2. Disconnect the steering pressure sensor connector. 3. Disconnect the water thermoswitch connector. 4. Disconnect the IAC valve connector. 5. Remove the intake air pipe. 6. Disconnect the wire and connector from the alternator. 7. Remove the alternator bolts and nut. 8. Remove the alternator. 9. Install in the reverse order of removal. Tightening torque Bolt 0: 38-51 N.m (3.8-5.3 kgf-m, 27-38 ftelbf) Bolt @ : 19-25 N.m j1.9-2.6 kgfem, 14--18 ft-lbf) Nut @I: 9.9--14 N.m (100-150 kgf-cm, 87-1 30 in-lbf) Gartner Banana

Before beginning any service procedure. refer to section T of this manual for air bag system service warnings and audio antitheft system alarm conditions . FRONT AND REAR AXLES ....................................... INDEX M- 2 ..................................... OUTLINE M- 3 SPECIFICATIONS ........................... M- 3 TROUBLESHOOTING GUIDE .................. M- 4 ............................... FRONT AXLE M- 4 ................................ REAR AXLE M- 4 ............................. DIFFERENTIAL M- 4 ................................. FRONT AXLE M- 5 PREPARATION ............................. M- 5 WHEEL HUB. STEERING KNUCKLE .......... M- 6 .................................. REAR AXLE M-10 PREPARATION ............................. M-10 ......................... DISC BRAKE TYPE M-11 ................................ DRIVE SHAFT M-17 .................... DOUBLE OFFSET JOINT M-17 ............................... DIFFERENTIAL M-23 PREPARATION ............................. M-23 DIFFERENTIAL OIL ......................... M-25 ................. OIL SEAL (OUTPUT SHAFT) M-25 DIFFERENTIAL. STANDARD; DIFFERENTIAL. TORQUE SENSING LIMITED SLIP ("TORSEN" LSD) ........................... M-27 45UOMX-001 "TORSEN" is a registered trademark of ZEXEL-GLEASON USA . INC Gartner Banana

TROUBLESHOOTING GUIDE TROUBLESHOOTING GUIDE FRONT AXLE I Problem Posslbk Cause Worn or damaged wheel bearing Worn or damaged wheel bearing Steering wheel vibration braking Action Replace Replace REAR AXLE Page M- 6 M-6 I Problem Possible Cause Bent drive shaft Page Action Replace I Abnormal nolse Worn or damaged wheel bearing Worn drive shaft spline Worn or deteriorated upper arm bushing M-13 Replace I M-17 Body "rolls" I Replace section R Body leans Weak upper arm bushing Abnormal nolse from suspension system Worn or deteriorated upper arm bushing DIFFERENTIAL Problem Posrlble Cause lnsufficient differential oil Incorrect differential oil lmproperly adjusted ring gear backlash Poor contact of ring gear teeth Worn or damaged side bearing Worn or damaged ring gear Worn or damaged drive pinion bearing Worn or damaged pinion and side gear (STANDARD) Worn or damaged gear in LSD assembly ("TORSEN" LSD) Seized side gear and case Worn side gear spline Worn pinion shaft Worn thrust washer Worn or damaged needle bearing ("TORSEN" LSD) lmproperly adjusted side gear backlash lmproperly adjusted drive pinion gear preload Action Add oil Replace Adjust Adjust Replace Replace Replace Replace Replace Page M-25 M-25 M40 M4l M-32 M-32 M-32 M-32 M-32 M-32 M-32 M-32 M-32 M-32 M-40 M-39 Abnormal nolse Replace Replace Replace Replace Replace Adjust Adjust Heat buildup lnsufficient differential oil lnsufficient drive pinion gear backlash Excessive bearing preload Add oil Adjust Adjust Oil leakage Excessive differential oil Loose differential carrier Worn or damaged oil seal Remove oil Tighten or repair Replace I - No dlfferentlal operation I Misassembled or damaged Repair Gartner Banana

FRONT AXLE WHEEL HUB, STEERING KNUCKLE Inspection / Removal / lnstallation 1. lnspect wheel bearing play, referring to Inspection. 2. Remove in the order shown in the figure, referring to Removal Note. 3. lnspect all parts and repair or replace as necessary. 4. Install in the reverse order of removal, referring to Installation Note. 25UOMX-OC 1. Front wheel 9. Lower arm 2. Brake caliper assembly Removal Note .............. page M-7 3. Disc plate 4. Hub cap 5. Locknut Installation Note ............ page M-7 6. Front wheel hub assembly lnspect for cracks and damage Disassembly / Inspection / Assembly ................. page M-8 7. Wheel speed sensor (ABS) 8. Tie-rod end Removal Note .............. page M-7 Service ..................... section N .............. Removal Note page M-7 ..................... Service section R 10. Upper arm .............. Removal Note page M-7 ..................... Service section R 11. Dust cover and knuckle spindle lnspect dust cover for damage and distortion lnspect knuckle spindle for cracks and damage Disassembly / Inspection 1 ................. Assembly page M-8 lnspection Wheel bearing play 1. Remove the wheel, brake caliper assembly, and disc plate, referring to Removal note below. 2. Position a dial indicator against the wheel hub. Push and pull the wheel hub by hand in the axial direction and measure the wheel bearing play. If the bearing play exceeds specification, check and adjust the locknut torque or replace the wheel hub i assembly if necessary. Maximum wheel bearing play: 0.05mm i0.002 in) Gartner Banana