1994 MAZDA MX-5 Workshop Manual

ELECTRICAL SYSTEM COMPONENTS Continuity 1. On level ground, jack up the vehicle and support it evenly on safety stands. 2. Disconnect the select lever from the manual shaft. 3. Disconnect the parwneutral switch connector. 4. Check continuity of the terminals. 0---0: Indicates continuity 5. If not correct, adjust the parwneutral switch. 6. If correct, check or adjust the selector lever. (Refer to page K-163.) Adjustment 1. Move the manual shaft to N position. 2. Loosen the parwneutral switch mounting Nuts. 3. Remove the screw on the switch body and move the parkheutral switch so that the screw hole is aligned with the small hole inside the switch. Check their alignment -i by inserting a 2.0mm (0.079 in) diameter pin through the holes. 4. Tighten the mounting nuts and remove the pin. Tightening torque: 5.0--6.8 N-m (50-70 kgfacm, 44--60 in-lbf) 5. Install and tighten the screw in the switch body. 6. Check the continuity of the parwneutral switch. 7. If not correct, replace the parklneutral switch. 8. Connect the selector lever. Tightening torque: 45-63 N.m (4.5-6.5 kgf-m, 33--47 ft-lbf) Gartner Banana

ELECTRICAL SYSTEM COMPONENTS K ATF THERMOSENSOR Inspection 1. Refer to "Replacement" below for removal of the ATF thermosensor. 2. Place the ATF thermosensor in ATF with a thermometer as shown, and heat the ATF gradually. 3. Measure resistance between the terminals of the ATF thermosensor. ATF temperature- {OF) 1 Resistance (kR) 20 (68) 2.5 4. If not correct, replace the ATF thermosensor. 5. Refer to "Replacement" for installation of the ATF ther- mosensor. Replacement 1. Disconnect the negative battery cable. 2. On level ground, jack up the vehicle and support it evenly on safety stands. 3. Disconnect the ATF thermosensor connector. 4. Remove the ATF thermosensor. 5. Install the new ATF thermosensor. Tightening torque: 7.9-1 0.7 N-m (80-11 0 kgf-cm, 70-95.4 in-lbf) 6. Connect the ATF thermosensor connector. 7. Connect the negative battery cable. VEHICLE SPEED PULSE GENERATOR Inspection 1. Disconnect the negative battery cable. 2. On level ground, jack up the vehicle and support it evenly on safety stands. 3. Disconnect the vehicle speed pulse generator connec- tor. 4. Measure resistance between the terminals of the vehicle speed pulse generator. Resistance: 24552 5. If not correct, replace the vehicle speed pulse generator. 6. Connect the vehicle speed pulse generator connector. 7. Connect the negative battery cable. Gartner Banana

K ELECTRICAL SYSTEM COMPONENTS Replacement 1. Disconnect the negative battery cable. 2. On level ground, jack up the vehicle and support it evenly on safety stands. 4 3. Disconnect the vehicle speed pulse generator connec- tor. 4. Remove the vehicle speed pulse generator. 5. Install the new vehicle speed pulse generator. Tightening torque: 7.9--10.7 N-m (80-110 kgfecm, 70-95.4 in-lbf) 6. Connect the vehicle speed pulse generator connector. 7. Connect the negative battery cable. 1-2 SHIFT, 2-3 SHIFT, 3-4 SHIFT, 3-2 CONTROL SOLENOID VALVE Inspection 1. On level ground, jack up the vehicle and support it evenly on safety stands. 2. Disconnect the solenoid valve connector. d 3. Measure resistance between each terminal and ground. Resistance: l3-27a 4. If not correct, check the wiring harness for an open or short circuit. Replace the solenoid valve. Solenoid valve 1-2 shift 2-3 shift 3-4 shift 3-2 control LOCKUP CONTROL SOLENOID VALVE lnspection 1. Disconnect the solenoid valve connector. 2. Measure the resistance between the terminals. Terminal C D - A B Resistance: l3-2Sil 3. If not correct, replace the solenoid valve. Gartner Banana

ELECTRICAL SYSTEM COMPONENTS K I POWERTRAIN CONTROL POWERTRAIN CONTROL MODULE (TRANSMISSION) lns~ection 1. kemove the powertrain control module (Transmission). (Refer to page K-45.) 2. Disconnect the control module connectors. 3. Connect the SSTs (Engine Signal Monitor and Adapt- er Harness) to the powertrain control module (Transmis- sion) as shown. 4. Place the SST (sheet) on the Engine Signal Monitor. 5. Turn the ignition switch ON. 6. Measure the terminal voltage at each terminal. 7. If any control module terminal voltage is incorrect, check the related input of output devices and wiring. If no prob- lem is found, replace the powertrain control module (Transmission). Caution Applying voltage to terminals A and B of this SST will damage the SST. Gartner Banana

K ELECTRICAL SYSTEM COMPONENTS Terminal Voltage Chart (Reference Data) C Terminal B+: Battery positlve voltage y Hold indicator light Condition Connected to 16 (Output) B+ Below 1.5V - - - No hold mode Hold mode FAT terminal (data link connector) I IC Voltage - - Voltmeter B+ Below 1.5V or B+ I C (Output) - - -- -- - - - -- -- - - - - - - - A- +terminal Normal If malfunction resent Ground (fluctuating) I Code Sianal I TAT terminal wounded -terminal Powertrain control module (Engine) (terminal R) TAT terminal (data link connector) - I - Below 2.5V 1 N or P range 1 D (Output) I Bt ]Other ranges I 1 E (lnput) 1 F 1 G I ATF thermosensor I 1G 3.3V ATF temperature 25OC {77"F) Ground B+ Switch depressed .-,/ -~ - 1 H (Input) 1 I Hold switch 1 OV ] Switch released I I 1 J (Output) 1 K 1 M (lnput) Cruise control unit I lM 1 N (lnput) Powertrain control module (Engine) (terminal 3M) 1 lN Idle switch B+ OV - -- Ve Accelerator pedal released I ADDrox. 4V While drivina Water temperature above 60°C {I 40°F) Accelerator pedal de~ressed Below 1.5V Vehicle speed sensor 1 P (lnput) 1 P I Approx' I Ignition switch ON I 4.4-5.5V 2A (Input) Throttle position sensor 1 2A . . . - . - . OV I lanition switch OFF 1 ParWneutral switch (N and P ranges) I OV I N or P ranae I 26 (Input) I B+ I Other ranaes I Gartner Banana

ELECTRICAL SYSTEM COMPONENTS K Terminal 2D (Input) 2E (Output) 2F (Input) 2G (Output) 2H (Input) - !I (Output) !J (Input)' - !K (Output) - !L (Ground)' 'M (Output) 1-2 shift solenoid valve 1 2E (S range) 2-3 shift solenoid valve Connected to Voltmeter I I +terminal . ParWneutral switch (D range) 2D - - (L range) 3-4 shift solenoid lalve Jehicle speed pulse 2J lenerator .ockup control ;olenoid valve 2K lehicle speed pulse 2L lenerator - 1 - I I - , - Z - 1 d - _4 3 V - - ower) E P (Ground) - 2P Ground ov - Q (Battery sattery 2Q B+ lgnition switch ON ower) OV Ignition switch OFF R - - - - - s (Battery Battery 2s B+ lgnition switch ON ~wer) Ground OV lgnition switch OFF Throttle position sen- 2T 'I- (Input) sor Approx. Throttle valve closed throttle position to wide 0.44.1 V open throttle Checked with AC range 1-2 control solenoid 'alve I 2M 1 ( Blow l.5V I 1 B+ 3-2 or 4-2 downshift OV Other conditions - - - I I I I lattery 20 B+ Constant Replacement Disconnect the negative battery cable. Disconnect the powertrain control module (Transmis- sion) connector. Remove the bolt and nut shown in the figure, and re- move the powertrain control module (Transmission). Install the new powertrain control module (Transmis- sion). Tightening torque: 19-25 N-m (1 .S2.6 kgf-m, 14--18 ftslbf) Connect the powertrain control module (Transmission). Connect the negative battery cable. Gartner Banana

TRANSMISSION TRANSMISSION UNIT (REMOVAL) Preparation SST 49 0259 440 Holder, mainshaft For prevention of oil leakage 1. Shift the selector lever to N range. 2. Disconnect the negative battery cable. 3. On level ground, jack up the vehicle and support it evenly on safety stands. 4. The oil pan could contain small chips, shavings, and other particles helpful in checking the condition of the transmission and diagnosing certain problems. To ensure that all foreign particles stay in the oil pan, make sure that the transmission is never tipped completely over while the oil pan is still installed. Warning When the transmission and the ATF are hot, they can cause burns to the skin. Allow the trans- mission and the ATF to cool before doing this procedure. 5. Drain the ATF into a suitable container. 6. Remove in the order shown in the figure, referring to Removal Note. 7. After removal, remove the oil pan to check condition of the transmission. Gartner Banana

TRANSMISSION K 1. Shift rod 12. Lockup solenoid connector 2. Undercover 13. Oil pipe 3. Performance rod 14. Harness 4. Exhaust pipe 15. Power plant frame (PPF) 5. Propeller shaft Removal Note ............. page K-48 Removal .................... section L 1 6. Undercover 6. Speedometer cable 17. Torque converter Nut - 7. Vacuum hose 18. Starter u 8. Parklneutral switch connector 19. Transmission mount bolt 9. Vehicle speed pulse generator connector 20. Transmission 10. Solenoid connector Removal Note ............. page K-49 11. ATF thermosensor connector Gartner Banana