1994 MAZDA MX-5 Workshop Manual

G CHARGING SYSTEM CHARGING SYSTEM PREPARATION SST T - DIODE TRIO C 49 9200 020 V-ribbed belt tension gauge y-- i BATTERY I - - For inspection of drive belt tension r-7 VOLTAGE REGULATOR L- A 05UOGX-008 CIRCUIT DIAGRAM B TERMINAL I S TERMINAL I Gartner Banana

CHARGING SYSTEM G TROUBLESHOOTING Check 1 Check if battery p Check battery (Refer to page G-8) J Check 2 I. Turn ignition switch ON Check wire harness 2. Check if voltage exists at each terminal of alternator Check 3 YES 1. Start engine Check alternator (Refer to page G-10) 2. Check if alternator warning light goes off I YES Check if drive belt t Adjust or replace drive belt (Refer to page G-14) 1 YES I Check for dark current (Refer to page G-3) I Check 1 BATTERY r"; Check 3 I ALTERNATOR WARNING LIGHT Check 2 B+: Battery positive voltage I I I B 1 Approx. 12V 1 Approx. 12V I B+ ON ON (Idle) L S 45UOGX-006 OV Approx. 12V Approx. 1V Approx. 12V B+ B+ Gartner Banana

CHARGING SYSTEM 1. Disconnect the battery cables from the battery. 2. Connect a voltmeter to the battery. BATTERY Warning Hydrogen gas is produced during normal battery d operation. A battery-related explosion can cause serious injury. Keep all flames (including ciga- rettes), heat, and sparks away from the top and surrounding area of open battery cells. Caution To prevent damage to electrical components or the battery, turn all accessories off and stop the engine before performing maintenance or re- charging the battery. Caution Obtain the code number and deactivate the audio anti-theft system before disconnecting the bat- tery. (Refer to section T.) Inspection Caution When disconnecting the battery, remove the neg- ative cable first and install it last to prevent dam- age to electrical components or the battery. Gartner Banana

CHARGING SYSTEM G Battery discharge test capable of reading 0.01V Quick charge for 30 min- utes and recheck voltage elo ow 12.4V Above 12.4V I Replace battery el c Apply test load (see test load chart) to the battery using a battery load tester Record battery positive voltage at the end of 15 seconds; is voltage more than specifica- tion? I Measure open circuit voltage of battery 1 Replace battery I I Below 12.4V Abov'e 12.4V Test load I Battew I Load (A1 I Battery posltive voltage with load I Charge battery ( I Battery OK I Terminal and cable 1. Clean and tighten the battery terminals and cables. 2. Coat the terminals with arease. 3. Inspect for corroded or 6ayed battery cables. 4. Check the rubber protector on the positive terminal for proper coverage. Recharging Warning Before performing maintenance or recharging the battery, turn off all accessories and stop the engine. The negative battery cable must be removed first and installed last. Battery S46A24L(S) Caution Do not remove vent caps. Follow carefully the instructions of the battery charger to prevent overcharging. u Do not recharging over 30 minutes to prevent damage the battery. Slow charge (A) Under 3 - -- Quick charge (A) Max. 20 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

CHARGING SYSTEM G Disassembly / Assembly 1. Disassemble in the order shown in the figure. 2. Assemble in the reverse order of disassembly. i/ 1. Pulley nut 6. Brush holder assembly 2. Pulley 7. Brush 3. Front cover Inspection ................. page G-12 4. Rotor 8. Rectifier Inspection ................. page G-12 Inspection ................. page G-13 5. Stator 9. Rear cover Inspection ................. page G-12 Gartner Banana

G CHARGING SYSTEM WEAR LIMIT LINE Inspection Rotor 1. Winding damage (1) Check the resistance between the slip rings with an J ohmmeter. Specification: 3.5--4.5SU20°C (68°F) (2) If it is not within specification, replace the rotor. 2. Ground of field coil (1) Check for continuity between each slip ring and the core with an ohmmeter. (2) Replace the rotor if there is continuity. 3. Slip ring surface If the slip ring surface is rough, use fine sandpaper to repair it. Stator 1. Wiring damage (1) Check for continuity between the stator coil leads with an ohmmeter. (2) Replace the stator if there is no continuity. 2. Ground of stator coil (1)~heck for no continuity between the stator coil leads and the core with an ohmmeter. (2) Replace the stator if there is continuity. Brush If the brushes are worn almost to or beyond the limit, replace them. Standard: 21.5mm (0.846 in) Minimum: 8.0mm (0.31 in) Gartner Banana

CHARGING SYSTEM G * ttt I E (HEAT SINK) 05UOGX-034 V RIBBED BELT X 0 X Brush Spring 1. Measure the force of the brush spring with a spring pres- sure gauge. 2. Replace the spring if necessary. Standard force: 3.14.3 N (0.32-444 kgf, 0.71-0.96 Ibf) Minimum: 1.6--2.4 N (0.16-0.24 kgf, 0.36-0.52 Ibf) Note Read the spring pressure gauge at a brush tip projec- tion of 2mm (0.079 in). Rectifier 1. Check for continuity of the diodes with an ohmmeter. I Negative (Black) I Positive (Red) I Continuity 1 I E I I Yes I -- 2. Replace the rectifier if necessary. DRIVE BELT Inspection 1. Remove the intake air pipe. 2. Check the drive belts for wear, cracks, or fraying. Replace if necessary. 3. Verify that the drive belts are correctly mounted on the pulleys. 4. Check the drive belt deflection when the engine is cold, or at least 30 minutes after the engine has stopped. Ap- ply moderate pressure (98 N, 10 kgf, 22 Ibf) midway between the specified pulleys. Deflection mm {in) I Drive belt New Used Alternator PIS, PIS + A/C 5.b7.0 {0.224.27) 8.0-9.0 iO.32-0.35) 6.W7.5 (0.24--0.29) 9.0-1 0.0 {0.36-0.391 Gartner Banana