wiring MAZDA MX-5 1994 Manual Online

ANTILOCK BRAKE SYSTEM (ABS) P ABS CONTROL UNIT 35-PIN CONNECTOR OHMMETER 15UOPX-OI Check rotor Check the rotor for missing or damaged teeth and replace as necessary. Check alternator Refer to section G. Check wheel-speed sensor Caution To prevent damage to the terminals, create a probe by wrapping a thin wire around the tester lead before inserting. 1. Using an ohmmeter, check for continuity at the control unit connector terminals. 0----0: Indicates continuity Right front Left rear Right rear 2. If the continuity is not as specified, check the wiring har- ness (Wheel-speed sensor - Control unit). 3. If the continuity is OK, check voltage between 1K and 1 G, 10 and 1 Q, 1 U and 1 F, and 1 L and 1 P while rotating the wheel one rotation per second by hand. 4. If voltage is not approximately 50 mV--60 mV, the wheel-speed sensor is faulty. 5. If voltage is approximately 50 mV-60 mV, the control unit is faulty. 1L Check hydraulics Verify that all brake fluid connections are tight and that no fluid is leaking. IP 1Q Left front 0--0 Check hydraulic unit wiring 1. Verify that the hydraulic unit connectors are properly secured. 2. Verify that the valve relay and motor relay are properly secured. IG 1K 0-4 1U 10 S-0 IF 0-4 Gartner Banana

P ANTILOCK BRAKE SYSTEM (ABS) Disassembly 1 Assembly 1. Disassemble in the order shown in the figure. 2. Assemble in the reverse order of disassembly, referring to Assembly Note. 2.2-2.6 Nm [22-27 kgfcm, 2&29 [2--3,14--22) 6.9-9.8 Nm (70-1 00 kgfcm, 81-47 Inlbf) 1 15--25 11 S-2.5,11-18) 19-25 [1.92.6,14--19) t4.m [kgfm, Wlbf) 25uopx-o: 1. Nut, washer . 2. ABS bracket 3. Connector bolt 4. Gasket 5. Pipe joint 6. Bolt 7. Clip Installation Note 8. Cover 9. Motor relay ................... Inspection page P-56 10. Valve relay ................... Inspection page P-57 11. Casing 12. Mount 13. Stud ................. below 14. Nut, washer 15. Ground wire 16. Hydraulic unit Assembly note A SECTION A-A Clip Secure only the larger part of the wiring harness in the clips. The 2-pin connector part of the harness should re- main outside the clips. Gartner Banana

P ANTILOCK BRAKE SYSTEM (ABS) RELAYS Removal 1 Inspection / Installation 1. Disconnect the negative battery cable. 2. Remove in the order shown. 3. Inspect all parts and replace as necessary. 4. Install in the reverse order of removal. 1. Cover 3. Valve relay 2. Motor relay Inspection ................... page P-57 Inspection ....................... below lnspection Motor relay 1. Disconnect the negative battery cable. 2. Release the motor relay lock from the hydraulic unit and remove the motor relay. 3. Connect an ohmmeter and check for continuity at the relay terminals. Ground M: Indicates continuity 4. If continuity is not as specified, replace the motor relay. 5. If OK, check the wiring harness (Motor relay - Control unit main fuse [ABS 60A1). Gartner Banana

OUTSIDE MIRROR Power outside mirrors do not operate 1 B+: Battery positive voltage 1 u Check CIGAR 15A fuse Replace fuse after checking and repairing wiring harness I Turn ignition switch to ON I ,,.,,,,,,,,,.,,,,.,. switch connector Repair harness (Fuse box - Power outside mirror switch) 1 OK I I I RIGHT i i~&) wire Disconnect power outside mirror switch connector Check for continuity between terminal wire (0) and ground Fbpair harness (Power outside mirror switch -Ground) 1 Check power outside mirror switch (Refer to page S-33) Reconnect power outside mirror switch connector Check for B+ at terminal wires of power outside mirror I I Switch position I Terminal I Voltage I UP I (BRl wire 1 B+ switch connector with mirror switch in positions indicated below NG c OK Right Left Check for B+ at terminal wires py of power outside mirror con- nector with mirror switch in positions indicated below Check power outside mirror (Refer to page S-33) - DOWN LEFT RIGHT UP DOWN LEFT RIGHT OK > ,- , - (LGIB) wire (LG/B) wire (B R/B) wire (BR) wire (LGIB) wire (LGIB) wire (BRIB) wire - Repair harness (Power outside mirror switch - Power outside mirror) B+ B+ B+ B+ B+ B+ B+ Gartner Banana

INSTRUMENT CLUSTER T L Symptom: Tachometer does not operate. 9MUOTX-069 Step 1 - Preparation 1. Remove the instrument cluster. (Refer to page T-29.) 2. Connect a test tachometer between terminals 1 H and 2J of the harness side connector. Step 2 1. Start the engine. 2. Check that the test tachometer indicates engine speed. Indicates rpm Yes No 7 Action Replace tachometer Repair wiring harness (Instrument cluster - laniter1 Gartner Banana

T INSTRUMENT CLUSTER Symptom: Water temperature gauge does not operate. 05UOTX-466 Preparation SST ( ) ... CANADA ONLY I 45UOTX-036 49 0839 285 Checker, fuel and thermometer 05UOTX-052 Step 1 1. Disconnect the water temperature sensor connector. 2. Connect the red lead of the SST to terminal A of the con- nector and the black lead to ground. 3. Turn the ignition switch to ON. 4. Set the SST to the resistance values shown in the figure. To get an accurate reading, wait 2 minutes after setting each value. 5. Verify that the water temperature gauge indicates the correct values. The allowable indication error is twice the width of the needle. For inspection of gauges Gauge display I Action Correct Incorrect I ( ) ... CANADA ONLY 45UOTX-038 T-26 Replace water temperature sensor Go to Step 2 Gauge display Correct Step 2 1. Remove the instrument cluster. (Refer to page T-29.) 2. Apply battery positive voltage to terminal 2K of the instrument cluster and connect terminal 2J of the instru- ment cluster to ground. 3. Connect the red lead of the SST to terminal 2L of the instrument cluster and the black lead to ground. 4. Set the SST to the resistance values shown in the figure. To get an accurate reading, wait 2 minutes after setting each value. 5. Verify that the water temperature gauge indicates the correct values. The allowable indication error is twice the width of the needle. Action Repair wiring harness (Instrument cluster - Water temperature sensor) I Incorrect I ReDlace water tem~erature aauae I Gartner Banana

INSTRUMENT CLUSTER T Symptom: Fuel gauge does not operate. L, Preparation SST Step 1 1. Disconnect the connector from the fuel gauge sender unit. 2. Connect the red lead of the SST to the A (Y) terminal wire and the black lead to ground. 3. Turn the ignition to ON. 49 0839 285 Checker, fuel and thermometer 4. Set the SST to the resistance values shown in the figure. To get an accurate reading, wait 2 minutes after setting each value. 5. Verify that the gauge indicates the correct values. The al- lowable indication error is twice the width of the needle. For inspection of gauges Gauge display Action I Step 2 1. Remove the instrument cluster. (Refer to page T-29.) 2. Apply battery positive voltage to terminal 2K and ground to terminal 2J. 3. Connect the red lead of the SST to terminal 1 A and the black lead to ground. Correct Incorrect 4. Set the SST to the resistance values shown in the figure. To get an accurate reading, wait 2 minutes after setting each value. 5. Verify that the gauge indicates the correct values. The al- lowable indication error is twice the width of the needle. Replace fuel gauge sender unit Go to Step 2 ( Gauge display I Action I Correct Incorrect Repakwiring harness (Instrument cluster - Fuel gauge sender unit) Replace fuel gauge Gartner Banana

T INSTRUMENT CLUSTER Symptom: Oil pressure gauge does not operate. 05UOTX-468 Preparation SST I 49 0839 285 For inspection of Checker, fuel gauges and thermometer Step 1 1. Disconnect the connector from the oil pressure sensor. 2. Connect the red lead of the SST to the A (YIR) terminal wire and the black lead to ground. 3. Turn the ignition switch ON. 4. Set the SST to the resistance values shown in the figure. To get an accurate reading, wait 2 minutes after setting each value. 5. Verify that the gauge indicates the correct values. The al- lowable indication error is twice the width of the needle. I Incorrect I GO to step 2 Gauge display Correct Step 2 1. Remove the instrument cluster. (Refer to page T-29.) 2. Apply battery positive voltage to terminal 2K and ground to terminal 2J. 3. Connect the red lead of the SST to terminal 26 and the black lead to ground. Action Replace oil pressure sensor 4. Set the SST to the resistance values shown in the figure. To get an accurate reading, wait 2 minutes after setting each value. 5. Verify that the gauge indicates the correct values. The al- lowable indication error is twice the width of the needle. Incorrect I Replace oil pressure gauge Gauge display Correct Action Repair wiring harness (Instrument cluster - Oil pressure sensor) Gartner Banana

T WARNING LIGHT AND SENDER UNIT TROUBLESHOOTING Check the METER 15A fuse in the fuse box before troubleshooting. If it is burnt, replace it after checking and repairing the wiring harness. i/ Brake System Warning Light I Symptom: Brake system warning light remains illuminated. 45UOTX-063 Step 1 - Check brake fluid level Check brake fluid level. Below MIN I I Check brake system (Refer to section P) I Brake fluid level Action Step 2 - Check parking brake switch 1. Disconnect the parking brake switch connector. 2. Check for continuity between the terminal of the switch and ground. Above MIN Go to Step 2 3. If not as specified, adjust or replace the parking brake switch. (Refer to section P.) 4. If the switch is OK, go to Step 3. I Step 3 - Check brake fluid level sensor I 1. Check for continuity of the sensor. *. 1' Lever Pulled one notch Released Continuity Yes No - I Above MIN No Brake fluid level Below MIN 2. If not as specified, replace the level sensor. 3. If the sensor is OK, repair the wiring harness. Continuity Yes Gartner Banana

WARNING LIGHT AND SENDER UNIT T Symptom: Brake system warning light does not illuminate when parking brake is on. (Ignition switch to ON) 45UOTX-065 Remedy 1. Disconnect the parking brake switch connector. 2. Check for continuity between the terminal of the switch and ground. I Released 1 No I Lever 3. If not as specified, adjust or replace the parking brake switch. 4. If the switch is OK, repair the wiring harness. Continuity 010 OFF Indicator Light Symptom: O/D off indicator light does not illuminate when O/D off switch turned on. 45UOTX-069 Pulled one notch I Yes Symptom: Brake system warning light does not illuminate when brake fluid in reservoir tank is below MIN. 45UOTX-067 Remedy 1. Check the bulb of the O/D off indicator light. 2. If the bulb is burned out, replace it. u Remedy 1. Disconnect the brake fluid level sensor connector. 2. Check for continuity of the brake fluid level sensor. Brake fluid level Below MIN Above MIN Continuity Yes No 3. If not as specified, replace the level sensor. 4. If the sensor is OK, repair the wiring harness. Gartner Banana