1994 MAZDA MX-5 bulb

G I ELECTRICAL TROUBLESHOOTING TOOLSIELECTRICAL PARTS I VOLTMETER I BLACK LINE GROUND ELECTRICAL TROUBLESHOOTING TOOLS TEST LIGHT 4) The test light, as shown in the figure, uses a 12V bulb. The two lead wires should be connected to probes.The test light is used for simple voltage checks and for check- ing for short circuits. Caution Using a bulb over 3.4W when checking the control unit may damage the control unit. JUMPER WIRE A jumper wire is used to create a temporary circuit. Con- nect the jumper wire between the terminals of a circuit to bypass a switch. Caution Do not connect a jumper wire from the power source line to a body ground; this may cause burning or other damage to harnesses or elec- tronic components. VOLTMETER The DC voltmeter is used to measure circuit voltage. A voltmeter with a range of 15V or more is used by con- necting the positive (+) probe (red lead wire) to the point where voltage is to be measured and the negative (-) probe (black lead wire) to a body ground. d OHMMETER The ohmmeter is used to measure the resistance between two points in a circuit, and to check for continu- ity and short circuits. I I 45UGIX-006 GI-I 4 Caution Do not connect the ohmmeter to any circuit to which voltage is applied; this will damage the ohmmeter. ELECTRICAL PARTS BAlTERY The battery installed in the right rear of the trunk is unique. When a replacement battery is installed, install it with a genuine Mazda battery replacement kit or equivalent. (Refer to section G.) J Gartner Banana

TROUBLESHOOTING GUIDE IT- MIL ALWAYS ON I ( DESCRIPTION I Self-Diagnosis Checker does not indicate Diagnostic Trouble Code No. but MIL always ON I I - - [TROUBLESHOOTING HINTS] Short circuit in wiring harness PCME malfunction ISTEP l INSPECTION I ACTION I 1 STEP 33 Disconnect (1 E) wire from PCME and check if MIL goes off 1 E MIL NEVER ON Ground (1 E) wire at PCME with jumper wire and check if MIL comes on 1 E Self-Diagnosis Checker indicates Diagnostic Trouble Code No. of input device but MIL never ON DEscR~pT~O~ I : Other indicator and warning lamps OK [TROUBLESHOOTING HINTS] Bulb burned out Open circuit in wiring harness PCME malfunction INSPECTION Yes No ACTION c3 If OK, replace PCME page F-143 I Q If not OK, repair PCME connector Replace PCME page F-143 Check for short circuit in wiring between combination me- ter and PCME page F-7 Yes No Check if bulb is OK I I Check connection condition of PCME connector tw page F-144 I r> If OK, repair (1 E) wire between PCME and combination meter as= page F-7 c3 If not OK, replace bulb Section T Gartner Banana

ANTILOCK BRAKE SYSTEM (ABS) P Inspection of ABS system Check system ground Caution To prevent damage to the terminals, create a probe by wrapping a thin wire around the tester lead before inserting. Check for an open circuit in (B) wire from terminals 1 Dl 1 S, and 2F of the control unit connector and ground. Check antilock warning light 1. Remove the instrument cluster. 2. Connect 12V to terminal 2K (C-Ol), and ground to termi- nal 1 K ((2-01). 3. Verify that the ABS warning light illuminates. 4. If there is no illumination, check the meter fuse, bulb, and wiring harness. 5. If OK, check the wiring harness (Warning light - Control unit - Hydraulic unit) and repair or replace as necessary. Check ABS diode 1. Check the meter fuse, bulb, and wiring harness. 2. Check the wiring harness (Warning light - Control unit - Hydraulic unit). 3. Disconnect the hydraulic unit 12-pin connector. 4. Using an ohmmeter, check for continuity of the terminals. 5. If continuity is not as specified, replace the hydraulic unit. Check front and rear valves 1. Disconnect the hydraulic unit 12-pin connector. 2. Using an ohmmeter, check for resistance of the termi- nals. -- 3. If resistance is not as specified, replace the hydraulic unit. 4. If resistance is as spe'cified, check the wiring harness (Hydraulic unit - ABS control unit). E (YIG) - H (B) (Rear Valve) C (BR) - H (B) (Right Front Valve) A (B/W) - H (B) (Left Front Valve) Check brake light switch 1. Disconnect the brake light switch connector. 2. Check for continuity between the terminals of the switch. Resistance (n) Approx. 1 .O-1.2 Approx. 1.0-1.2 Approx. 1 .+I .2 M : Indicates continuity Depressed brake pedal 3. If the continuity is not as specified, check the STOP fuse and wiring harness (Brake light switch - Control unit). 0 I 0 Released brake pedal 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

T WARNING LIGHT AND SENDER UNIT Remedy 1. Disconnect the timer and buzzer unit connector. 2. Turn the ignition switch ON, and verify that the seat belt warning light illuminates. I Warning light illuminates I Action Seat Belt Warning Light The seat belt warning light is controlled by the timer and buzzer unit. 1 Reolace timer and buzzer unit I Symptom: Seat belt warning light remains on six seconds after ignition switch is turned on. (Timer function does not operate.) I Yes Repair wiring harness (Instrument cluster - Timer and buzzer unit) I d 1 Symptom: Seat belt warning light does not illuminate when ignition switch is first turned on. I 45UOTX-070 Step 1 1. Ground terminal J of the timer and buzzer unit connector. 2. Turn the ignition switch ON, and verify that the seat belt warning light illuminates. 1 Warning light illuminates I Action I Step 2 1. Ground terminal D of the timer and buzzer unit connec- tor. 2. Turn the ianition switch ON. and verifv that the seat belt No Yes warning light illuminates. . Go to Step 2 Repair wiring harness (Timer and buzzer unit - GND) Warning light Illuminates Action Replace timer and buzzer unit Check bulb of seat belt warning light If bulb is OK, repair wiring harness (Instrument cluster - Timer and buzzer unit) Gartner Banana

WARNING LIGHT AND SENDER UNIT T OHMMETER Washer Level Indicator lnspection 1. Disconnect the connector from the washer level sensor. 2. Jump terminal-wire L (harness side) to a body ground. 3. Start the engine and check that the WASHER indicator illuminates. 4. If there is no illumination, check the bulb, wiring harness, and sensor. Replace or repair as necessary. Washer Level Sensor lnspection 1. Connect the sensor connector (sensor side) to an ohm- meter. 2. Move the sensor float up and down. 3. Verify that there is continuity when the float is at the low- est point. BRAKE FLUID LEVEL SENSOR lnspection 1. Check for continuity of the sensor. 2. If continuity is not as specified, replace the level sensor. Float level Below MIN Above MIN BUCKLE SWITCt Continuity Yes No OHMMETER -1 PARKING BRAKE SWITCH lnspection 1. Disconnect the parking brake switch connector. 2. Check for continuity between the switch connector and ground. I Lever I Continuity I 3. If continuity is not as specified, adjust or replace the parking brake switch. (Refer to section P.) Pulled one notch Released BUCKLE SWITCH lnspection 1. Disconnect the buckle switch connector 2. Check for continuity of the switch. Yes No Seat belt I Continuity Seat belt buckled Seat belt unbuckled No Yes 3. If continuity is not as specified, replace the buckle switch. Gartner Banana

LIGHTING SYSTEM T LAY Step 2 1. Turn the headlight switch ON. 2. Measure the voltage at the following terminal-wires of the headlight relay connector. B+: Battery positive voltage Other Action Go to Step 3 Check B terminal Go to Step 6 Check A terminal Check D terminal Repair wirring harness Repair wiring harness (HEAD 30A - Headliclht relav) I Step 3 1. Turn the headlight switch ON. 2. Measure the voltaae at the followinn terminal-wires of - the headlight switch connector. B+: Battery positive voltage Termlnal I Switch position I Voltage / Action I Check I terminal switch) Low beam G B+ Other - Go to Step 4 Replace combination switch High beam Step 4 1. Check the headlight bulbs. 2. If a bulb is burned, replace it. 3. If the bulbs are OK, go to Step 5. B+ Other Go to Step 4 Replace combination switch Gartner Banana

LIGHTING SYSTEM T I Symptom: Headlight does not illuminate (Right or left). I Step 1 1. Check the headlight bulbs. 2. If a bulb is burned, replace it. 3. If the bulbs are OK, go to Step 2. Step 2 1. Disconnect the headlight connector of the faulty side. 2. Turn the headlight switch on. 3. Measure the voltage at the following terminal wires. B+: Battery positive voltage Other IB(FVW) Highbeam Action Repair wiring harness (Retractable headlight - GND) Repair wiring harness (Combination switch - Retract- able headlight) Repair wiring harness (Retractable headlight - GND) Repair wiring harness (Combination switch - Retract- able headlight) Gartner Banana