charging MAZDA MX-5 1994 User Guide

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

CHARGING SYSTEM I AIC EQUIPPED I WHEN MEASURED 45UOGX-015 - ADJUSTING BOLT I I 5. Check the drive belt tension with a tension gauge. Note Belt tension can be measured between any pulleys. J Tension N {kgf, Ibf) A belt that has been on a ruining engine for less than five minutes. Alternator 'IS
+ A/C 6. Install the intake air pipe. Used Drive belt Adjustment New* I Caution If a new belt is used, adjust the belt deflection at the midpoint of new belt specification. 491-745 (50-76,110-167) 49 1-588 (50-60, 11 0-1 32) d (1) Alternator belt Loosen the alternator bolts @ and @ and adjust the belt deflection by turning the adjusting bolt 0. 491-706 (50-72,110-158) 422490 (43-50,95--110) Tightening torque @: 19-25 N.m (1.9-2.6 kgf.m, 14-1 8 ft4bf) @: 38-51 N.m (3.8-5.3 kgf,m, 28-38 ft-lbf) (2) PIS belt, PIS + AIC belt Loosen the PIS oil pump bolts @ and @ and nut 0, and adjust the belt deflection by turning the adjusting bolt 0. Tightening torque @: 3246 N.m (3.24.7 kgf.m, 24--33 ft4bf) @: 37-53 N.m (3.7-5.5 kgf,m, 27-39 ft-lbf) 0: 19-25 N.m (1.9-2.6 kgf-m, 14-1 8 ft-lbf) (3) AIC belt Loosen the locknut and adjust the belt deflection by turning the adjusting bolt. Tightening torque: 38-51 N.m (3.8-5.3 kgf-m, 28-38 ft-lbf) Gartner Banana

TROUBLESHOOTING Case 2: Excessive refrigerant or insufficient condenser cooling Measured pressure Low-pressure side: 0.254.34 MPa (2.5--3.5 kgf/cm2, 3-9 psi) High-pressure side: 1.97-2.45 MPa (20.0-25.0 kgflcm*, 285--355 psi) Condition Outlet air from vents not cold. Note If the condenser fan does not operate when the air conditioner is operating, see "Condenser fan does not operate"; page U-9, before proceeding. Step 1 1. Make sure the condenser fan operates when the air con- ditioner is operating. If it does not operate, troubleshoot the condenser fan circuit (page U-9) before proceeding. 2. Check the condenser for bent fins or damage. Repair or replace if necessary. 3. If the condenser is OK, go to Step 2. Step 2 Verify that the refrigerant pressure is normal. Case 3: Air in system Measured pressure Low-pressure side: 0.254.29 MPa (2.5--3.0 kgflcmz, 36-42 psi) High-pressure side: 1.97-2.45 MPa (20.0-25.0 kgf/cm2, 285--355 psi) Condition Insufficient cooling. CAUSE ACTION 7 EVACUATE SYSTEM Step 1 Discharge the refrigerant system. Step 2 Evacuate the system to remove all air from it. (Refer to page U-25.) Step 3 Charge the system with refrigerant. (Refer to page U-25.) Step 4 After charging, measure the refrigerant pressure. (Refer to page U-29.) .- Step 5 If low- and high-pressure sides are still too high, replace the receiver drier. Gartner Banana

TROUBLESHOOTING Case 4: Moisture in system Measured pressure Low-pressure side: Vacuum High-pressure side: 0.69-4.98 MPa (7.O-lO.O kgf/cm2, 100-1 42 psi) Condition Insufficient cooling. (Moisture in refrigeration system freezes in expansion vaive and causes temporary block- ing. After time, ice melts and condition returns to normal.) CAUSE n MOISTURE IN I SYSTEM le ACTION EVACUATE SYSTEM Step 1 Discharge the refrigerant system. Step 2 Evacuate the system to remove all air and moisture from it. (Refer to page U-25.) Step 3 Charge the system with refrigerant. (Refer to page U-25.) Step 4 After charging, measure the refrigerant pressure. (Refer to page U-29.) Step 5 if low- and high-pressure sides are still too low, replace the receiver drier. Case 5: No refrigerant circulation Measured pressure Low-pressure side: Vacuum ~ighLpressure side: 0.50--0.58 MPa (5.0--6.0 kgf/cm2, 72-45 psi) Condition b Refrigerant flow obstructed by moisture or dirt, causing freezing or blockage of expansion valve. CAUSE ACTION MOISTURE IN CAUSE ACTION Step 1 Turn off the air conditioner for about 10 minutes. Turn on the air conditioner to determine whether the biockage is due to moisture or dirt. a) If caused by moisture System will operate normally after being off for 10 min- utes. (Ice melts and relieves blockage.) Refer to "Moisture in system"; page U-13. b) If caused by dirt System remains abnormal after being off 10 minutes. Go to Step 2. DIRT IN SYSTEM Step 2 1. Remove the expansion valve. (Refer to page U-31.) 2. Blow out the dirt with compressed air. 3. If unable to remove the dirt, replace the expansion valve. 4. Evacuate, charge, and test the system. CLEAN OR REPLACE EXPANSION VALVE Gartner Banana

AIR CONDITIONER u NIFOLD GAUGE CHARGING HOSE (HI) QUICK COUPLER REFRIGERANT SYSTEM SERVICE PROCEDURE Manifold Gauge Set Installation 1. Fully close the valves of the manifold gauge. 2. Connect charging hoses to the high and low-pressure- side joints of the manifold gauge set. 3. Connect quick couplers to the ends of the charging hoses. 4. Remove the caps from the charging valves of the high and low-pressure-side cooler pipes. 5. Connect the quick couplers to the charging valves of the cooler pipes. Charging 1. Install the manifold gauge set. 2. Connect the tap pin side of the charging hose to the air purge valve of the gauge set. 3. Connect the vacuum pump hose to the center joint of the gauge set. 4. Connect the vacuum pump hose to the vacuum pump. 5. Connect can puncture valves to 4-way joint. 6. Fully open the can puncture valves and connect service cans to the valves. Regular amount of refrigerant: 600 g (21.2 oz) 7. Fully close any can puncture valve that is not connected to a service can. 8. Connect the 4-way joint to the charging hose that is con- nected to the gauge set air purge valve. 9. Open all the valves of the manifold gauge set. 10. Start the vacuum pump and let it operate for 15 minutes. 11'. After 15 minutes, verify that the high and low-pressure- side readings of the manifold gauge set are at -1 01 kPa {-760 mmHg, -29.9 inHg}. Close each valve of the gauge set. 12. Stop the vacuum pump and wait for about 5 minutes. 13. After 5 minutes, check the low-pressure-side reading of the gauge set. If the reading changed, check for leaks and then repeat from step 9. If the reading has not changed, go to step 14. 14. Open the service cans by using the can puncture valves. 15. Open the low-pressure-side valve of the manifold gauge set and charge with refrigerant unit the low-pressure- side reading is at 100 kPa (1 kgf/cm2, 10 psi). 16. Close the low-pressure-side valve of the gauge set. Gartner Banana

u AIR CONDITIONER LEAK TESTER I LEAK TESTER I 17. Check for leaks by using a leak tester. If there are no leaks, go to step 18. If a leak is found at loose joint, tighten the joint and check for leaks again. If there is still a leak at the same joint, dis- 4 charge the refrigerant and then repair the joint. Repeat the charging procedure from step 9. If there are no leaks after tightening the joint, go to step 18. Warning Running the engine with the high-pressure-side valve open is dangerous. Pressure within the ser- vice cans will increase and the cans could ex- plode, scattering metal fragments and liquid refrigerant that can seriously injure you. There- fore, do not open the high-pressure-side valve while the engine is running. 18. Open the low-pressure-side valve of the manifold gauge set and charge with the regular amount of refrigerant. 19. Close the low-pressure-side valve of the manifold gauge set. 20. Check for leaks by using a leak tester. If there are no leaks, go to step 21. If a leak is found at loose joint, tighten the joint and check for leaks again. If there is still a leak at the same joint, dis- charge the refrigerant and then repair the joint. Repeat the charging procedure from step 9. If there are no leaks after tightening the joint, go to step 21. 21. Disconnect the high and low-pressure-side quick cou- plers from the charging valves that are connected to the high and low-pressure-side cooler pipes of the refriger- ant system. 22. Install the caps to the charging valves of the cooler pipes. Gartner Banana

AIR CONDITIONER u Refilling Caution If there is too much refrigerant in the system, pressure cannot be fixed at an appropriate level to change the gas to a liquid. Do not overcharge the system. 1. Install the manifold gauge set. (Refer to page U-25.) 2. Connect the tap pin side of the charging hose to the air purge valve of the gauge set. 3. Connect the vacuum pump hose to the center joint of the gauge set. 4. Connect the vacuum pump hose to the vacuum pump. 5. Connect can puncture valves to a 4-way joint. 6. Fully open the can puncture valves and connect service cans to the valves. 7. Full close any can puncture valve that it is not connected to a service can. 8. Connect the 4-way joint to the charging hose that is con- nected the gauge set air purge valve. 9. Open only the center valve of the manifold gauge set. 10. Start the vacuum pump and let it run for 5 minutes. 11. After 5 minutes, close the center valve of the manifold gauge set. 12. Stop the vacuum pump. Warning Running the engine with the high-pressure-side valve open is dangerous. Pressure within the ser- vice cans will increase and the cans could ex- plode, scattering metal fragments and liquid refrigerant that can seriously injury you. Therefore, do not open the high-pressure-side valve while the engine is running. 13. Open the service can by using the can puncture valve. 14. Start the engine and actuate the A/C compressor. 15. Open the low-pressure-side valve and refill with refriger- ant until the bubbles in the sight glass disappear and the high and low-pressure readings of the manifold gauge set are within normal pressure limits. (Refer to page U-29.) 16. Stop the engine and the NC compressor. 17. Disconnect the high and low-pressure-side quick cou- plers from the charging valves that are connected to the high and low-pressure-side cooler pipes of the refriger- ant system. 18. Install the caps to the charging valves of the cooler pipes. 45UOUX-060 Gartner Banana

AIR CONDITIONER REFRIGERANT PRESSURE SWITCH OPERATION 206 {2.1,30) 3,140 (32.0, 455) OFF ON n 230 {2.3,33) 2,550 (26.0,370) A/C RELAY Inspection 1. Remove the relay. 2. Apply battery positive voltage and check for continuity between terminals of the relay. B+: Battery positive voltage 3. If not as specified, replace the relay. CONDENSER FAN RELAY lnspection 1. Remove the relay. 2. Apply battery positive voltage and check for continuity between terminals of the relay. B+: Battery positive voltage 1 2 O--(): Continuity 3. If not as specified, replace the relay. 0 B+ 1 2 REFRIGERANT PRESSURE SWITCH lnspection If problems occur in the refrigerant system that cause ab- normally high pressure or abnormally low pressure, the pressure switch will cut power to the magnetic clutch to protect the mechanical components. If the pressure re- covers to within normal operating range, the power will be restored. These operating values are shown in the figure. kPa (kgf/cm2, psi) 35UOUX-020 1. Connect a manifold gauge set to the charging valve. 2. Verify that the high-pressure-side pressure is 230-2,550 kPa (2.3-26.0 kgf/cm2, 33-370 psi). 3. Disconnect the refrigerant pressure switch connector and check for continuity between the switch terminals. 4. If there is no continuity, replace the refrigerant pressure switch. 45UOUX-085 0 GND 0 B+ 0 0 GND 0 0 0 0 3 Gartner Banana