battery MAZDA MX-5 1994 Owners Manual

CONTROL SYSTEM F Connection to I Test condition I Hot condition: Enaine coolant Input - temp. above 70°C (1 58"~) and in- PRC solenoid valve take air temp. above 50°C (122°F) for 150 sec. after enaine startina Output 0 0 0 0 0 0 0 0 0 " " Other conditions lanition switch On - Condenser fan relay Engine coolant temp. Idle above 108°C 1226°F) I I Other conditions ' I lgnition switch ON Fuel pump relay ldle I I lanition switch ON Fuel injector No.1 1,900 rpm (After warm-UD) I lgnition switch ON Fuel injector No.2 ldle Deceleration from 3,000 rprn to 1,900 rpm (After warm-up) lgnition switch ON IAC valve ldle lgnition switch ON Purge solenoid valve ldle Fuel injector No.3 lgnition switch ON ldle Deceleration from 3,000 rpm to 1,900 rpm (After warm-up) lanition switch ON Fuel injector No.4 Idle Deceleration from 3,000 rpm to 1,900 rpm (After warm-up) Below 1 .OV -1 Below 1 .OV B+ - Approx. OV Engine Signal Moni- * Engine Signal Moni- tor: Green and red Approx. 12V I lamps flash B+: Battery positive voltage Voltage I Remark * Engine Signal Moni- tor: Green and red Engine Signal Moni- Gartner Banana

CONTROL SYSTEM Check Point for Each Terminal B+: Battery positive voltage Terminal -. - Connection to Abnormal voltage Possible cause Battery Always OV (Battery OK) Always OV Main relay a ROOM 10A fuse burned Open circuit in wiring from ROOM 1 OA fuse to PCME terminal 1A Main relay malfunction (Refer to page F-156) Open circuit in wiring from main relay to PCME termi- nal 1 B Ignition switch (Start position) a Main relay malfunction (Refer to page F-156) Open circuit in wiring from main relay to data link connector terminal +B Open or short circuit in wiring from data link connec- tor terminal MEN to PCME terminal 1 D Always OV (Starter turns) Always OV Open circuit in wiring from starter interlock switch to PCME terminal 1 C Self-Diagnosis Checker (Monitor lamp) Always B+ a Poor connection at PCME connector PCME malfunction I Always approx. 5V I a PCME malfunction Malfunction indicator light (MIL) Always below 2.5V (MIL always ON) Always below 2.5V Open circuit in wiring from combination meter to (MIL never ON) I PCME terminal I E a Short circuit in wiring from combination meter to PCME terminal 1 E PCME malfunction Always B+ Poor connection at PCME connector a PCME malfunction Self-Diagnosis Checker (Code No.) Always below 2.5V (No display on Self-Diagnosis Checker) Main relay malfunction (Refer to page F-156) a Open circuit in wiring from main relay to data link connector terminal +B Always B+ Always below 2.5V ("88" is displayed and buzzer sounds continuously) a Poor connection at PCME connector a PCME malfunction - Open or short circuit in wiring from data link connec- tor terminal FEN to PCME terminal I E Igniter Always OV a Refer to Code No.01 troubleshooting I (Refer to section GI Powertrain control module (transmission) Always B+ I PCME malfunction A/C relay malfunction (Refer to section U) a Open circuit in wiring from main relay to NC relay a Open circuit in wiring from NC relay to PCME termi- nal 1 J a Short circuit in wiring from NC relay to PCME termi- nal 1 J a PCME malfunction Always below 2.5V (NC does not operate) Always below 2.5V (Air conditioning sensor OFF but A/C operates) AIC relay Air conditioning sensor malfunction (Refer to section U) Poor connection at PCME connector PCME malfunction Always B+ Open circuit in wiring from PCME terminal 1 K to ground PCME malfunction Ground (MT) Always B+ Open (AT) Always OV Short circuit in wiring from PCME terminal 1 K to grounc PCME malfunction Coolant fan relay Always below 1 .OV (Coolant fan OK) Open or short circuit in wiring from fan relay to PCME terminal I L PCME malfunction 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

F CONTROL SYSTEM B+: Battery positive voltage Abnormal voltage Possible cause Terminal 1 v Connection to Neutral switch malfunction (Refer to page F-157) Clutch switch malfunction (Refer to page F-156) Short circuit in wiring from PCME terminal 1 V to neutral or clutch switch Neutral switch malfunction (Refer to page F-157) 0 Clutch switch malfunction (Refer to page F-156) 0 Open circuit in wiring from PCME terminal 1 V to neutral or clutch switch Poor connection at PCME connector 0 ParWneutral switch malfunction (Refer to section K) 0 Short circuit in wiring from parWneutral switch to PCME terminal 1V 0 ParWneutral switch malfunction (Refer to section K) 0 Open circuit in wiring from parWneutral switch to PCME terminal 1 V Always OV Neutral switchlClutch switch (MT) Always B+ Always OV ParWneutral switch (AT) Always B+ Poor contact at ground terminal 0 Open circuit in wiring from PCME to ground Sround More than OV Crankshaft position sensor (SGT-signal) Always OV or approx. 5V Always below 2V or 4V Refer to Code No.03 troubleshooting (Refer to page F-84) Refer to code No.08 Troubleshooting (Refer to page F-86) 0 Short circuit in wiring from PCME terminal 2H to data link connector terminal TEN Mass airflow sensor Always OV Data link connector (Terminal TEN) 0 Open circuit in wiring from PCME terminal 2H data link connector terminal TEN 0 Open circuit in wiring from data link connector terminal GND to around Always B+ Igniter EGR function sensor Always OV Always approx. OV or approx. 5v Refer to Code No.01 troubleshooting (Refer to paae F-83) 0 Refer to Code No.16 Troubleshooting (Refer to page F-89) 0 Short circuit in wiring from PCME terminal 2K tothrottle position sensor, PCME, or mass airflow sensor Poor connection at PCME connector PCME malfunction Vre f Always OV lllumination light ON when rear window defroster switch ON Open or short circuit in wiring from rear window de- froster switch to PCME terminal 2L Always below 1 .ov Rear window defroster switch Open circuit in wiring from ignition switch to rear win- dow defroster switch Rear window defroster switch malfunction (Refer to section T) lllumination light never ON Open circuit in wiring from PCME terminal 2M to throttle position sensor 0 Open circuit in wiring from PCME terminal 2K to throttle position sensor 0 Open circuit in wiring from PCME terminal 20 to throttle position sensor Always constant Throttle position sensor Alwavs above 1V 0 Throttle position sensor misadjustment Refer to Code No.15 troubleshooting (Refer to page F-88) OV after warm-up Heated oxygen sensor Always approx, 1V after warm-up 0 Refer to Code No.17 troubleshooting (Refer to page F-90) Refer to Code No.08 troubleshooting (Refer to page F-86) Mass airflow sensor Always OV or approx. 5V Gartner Banana

CONTROL SYSTEM B+: Battery positive voltage Terminal Connection to Abnormal voltaae Possible cause Mass airflow sensor (Intake air temperature sensor) Refer to Code No.10 troubleshooting (Refer to page F-87) Always OV or approx. 5V Intake air temperature sensor malfunction (Refer to page F-152) Refer to Code No.09 troubleshooting (Refer to page F-87) Engine coolant temper- ature sensor Always OV or approx. 5V r Engine coolant temperature sensor malfunction (Refer to page F-154) Refer to Code No.25 Troubleshooting (Refer to page F-91) Always OV or B+ PRC solenoid valve r Open or short circuit in wiring from condenser fan relay to PCME terminal 25 PCME malfunction Open or short circuit in wiring from fuel pump relay to PCME terminal 2T Condenser fan relay Always below 2.OV Fuel pump relay Always below 1 .OV Main relay malfunction (Refer to page F-156) r Open or short circuit in wiring from fuel injector to PCME terminal 2U or 2V Always OV Fuel injector ldle air control valve Purge solenoid valve Always B+ Always OV or B+ Always OV or B+ PCME malfunction r Refer to Code No.34 troubleshooting (Refer to page F-93) ldle air control solenoid valve malfunction (Refer to page F-I 06) r Refer to Code No.26 troubleshooting (Refer to page F-91) r Purge solenoid valve malfunction (Refer to pane F-132) -- Fuel injector Always OV Main relay malfunction (Refer to page F-156) Open or short circuit in wiring from fuel injector to PCME terminal 2Y or 22 Always B+ PCME malfunction Gartner Banana

CONTROL SYSTEM LOCK 4. If not as specified, replace the main relay. MAIN RELAY lnspection 1. Verify that the main relay clicks when turning the ignition switch OFF -+ ON. 2. Apply battery positive voltage to terminal A and ground terminal B of the main relay. 3. Use an ohmmeter to check continuity of the terminals as shown. CLUTCH SWITCH Inspection 1. Disconnect the clutch switch connector. 2. Connect an ohmmeter to the switch. 3. Check continuity of the switch. Battery positive voltage applied - Continuity - Terminals CD L 4. If not as specified, replace the clutch switch. Battery positive voltage not applied No continuity Pedal Depressed Released Replacement 1. Disconnect the clutch switch connector. 2. Loosen the locknut. 3. Remove the clutch switch. 4. Install in the reverse order of removal. 5. Adjust the pedal height. (Refer to Section H.) Continuity Yes No 4. If not as specified, replace the neutral switch. NEUTRAL SWITCH lnspection 1. Disconnect the neutral switch connector. 2. Connect an ohmmeter to the switch. 3. Check continuity of the switch. Transmission Neutral Other ranges Continuity , Yes No 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 . ENGINE ELECTRICAL SYSTEM INDEX ....................................... G- 2 OUTLINE ..................................... G- 3 SPECIFICATIONS ........................... G- 3 TROUBLESHOOTING GUIDE .................. G- 4 CHARGING SYSTEM .......................... G- 6 PREPARATION ............................. G- 6 CIRCUIT DIAGRAM ......................... G- 6 TROUBLESHOOTING ....................... G- 7 BATTERY .................................. G- 8 ALTERNATOR .............................. G-10 DRIVE BELT ................................ G-13 IGNITION SYSTEM ............................ G-15 PREPARATION ............................. G-15 CIRCUIT DIAGRAM ......................... G-15 TROUBLESHOOTING ....................... G-16 IGNITION TIMING ........................... G-17 SPARK PLUG ............................... G-18 IGNITION COIL ............................. G-19 IGNITER ................................... G-19 HIGH-TENSION LEAD ....................... G-20 STARTING SYSTEM ........................... G-21 CIRCUIT DIAGRAM ......................... G-21 TROUBLESHOOTING ....................... G-21 STARTER .................................. G-22 STARTER INTERLOCK SWITCH (MT) ......... G-28 45UOGX401 Gartner Banana

G INDEX INDEX 1. Battery lnspection . . . . . . . . . . . . . . . . . page G- 8 Recharging . . . . . . . . . . . . . . . . page G- 9 Replacement . . . . . . . . . . . . . . page G-10 2. Alternator Removal / lnstallation . . . . . . . page G-10 Disassembly / Assembly . . . . page G-11 lnspection . . . . . . . . . . . . . . . . . page G-12 3. Drive belt lnspection . . . . . . . . . . . . . . . . . page G-13 Adjustment . . . . . . . . . . . . . . . . page G-14 4. Spark plug Removal / Installation . . . . . . . page G-18 Spark test . . . . . . . . . . . . . . . . . page G-18 lnspection . . . . . . . . . . . . . . . . . page G-18 5. Ignition coil lnspection . . . . . . . . . . . . . . . . . page G-19 Replacement . . . . . . . . . . . . . . page G-19 6. Igniter (in ignition coil) lnspection . . . . . . . . . . . . . . . . . page G-19 7. High-tension lead Removal / lnstallation . . . . . . . page G-20 lnspection . . . . . . . . . . . . . . . . . page G-20 8. Starter Removal / lnstallation . . . . . . . page G-22 Performance lnspection . . . . . page G-23 Disassembly / Assembly . . . . page G24 -' lnspection . . . . . . . . . . . . . . . . . page G26 9. Starter interlock switch (MT) lnspection . . . . . . . . . . . . . . . . . page G-28 Gartner Banana

OUTLINE OUTLINE SPECIFICATIONS (i.e. powertrain control module (engine), audio, etc.) *2 With System Selector (49 B019 9AO) test switch at SELF TEST. - Engine Item Starter Ignition system Cylinder Arrangement Battery BP DOHC MT I AT 12, Negative ground S46A24L(S) (32 Ah) Maintenance-free 20.0 A.C. I REAR Voltage V Type and capacity (5-hour rate) 12-65 -. 1 2-70 Drive belt deflection mm {in} Dark current" m A Transistorized (built-in voltage regulator) 14.3-1 4.9 21.5 I0.846) 8 (0.31 1 Ignition timing** BTDC ("CA)lrpm U Alternator 'I Dark current is the constant flow of current while the ignition switch is OFF. 45UoGX-003 New Used 101850 Ignition coil Spark plug FRONT 55-7.0 (0.22-0.27) 6.0-7.5 (0.2H.29) 101800 TY pe Primary coil winding n Secondary coil winding kR Type Plug gap mm {in) Firing order Type Output V-A Regulator type Regulated voltage V TY pe Output V-kW Molded (with igniter) - 8.7-1 2.9 (20°C (68°F)) NGK : BKR5E-11 BKR6E-11 (Standard ... MT) NIPPONDENSO : K16PR-U11 K20PR-U11 (Standard ... MT, AT) 1 .O-1.1 IO.040-0.043) 1-3-4--2 Brush length mm {in) Direct 124.95 17.0 i0.67) 11.5 I0.45) Brush length mm {in} Standard Minimum Coaxial reduction 12-1.4 17.5 i0.69) 12.0 i0.47) Standard Minimum Electronic spark advance (ESA) Powertrain control module (engine) controls spark advance Type Spark advance control Gartner Banana

TROUBLESHOOTING GUIDE TROUBLESHOOTING GUIDE Problem Will not crank Cranks slowly Discharged battery Misfire G-5 Will not crank I Will not crank I Check 1 1 , YES, Check if engine cranks with fully charged battery Check charging system (Refer to page G-7) I NO Check ignition switch (Refer to section T), starter interlock switch (Refer to page G-28) and parWneutral switch (Refer to section K) 45uOOx-OC - Check 1 Check if click is heard from starter magnetic switch when ignition is turned to START Cranks slowly Check starting system (Refer to page G-21) Crank slowly Check 1 Check charging system (Refer to page G-7) I NO ---- Check starting system (Refer to page G-21) Check 1 Gartner Banana