FixVault
Home › Mazda › 1994 › B3000 Base, 2D Pickup, Standard › Repair and Diagnosis › Accessories & Equipment › Cruise Control Systems › Circuit Testing › Control Switch & Circuit

Control Switch & Circuit

NOTE: DO NOT use a test light to perform the following tests.
  1. Step on brake pedal. Check for proper stoplight operation. Repair stoplight circuit as necessary. See STOPLIGHT SWITCH & CIRCUIT TEST. Press horn button. If horn does not sound, repair horn circuit. See HORN RELAY CIRCUIT TEST. If stoplights and horn operate properly, go to next step.
  2. Turn ignition off. Locate amplifier 6-pin connector behind right side of dash, above glove box. Backprobe connector using Digital Volt-Ohmmeter (DVOM). Check continuity between Black wire terminal of amplifier connector and ground. Repair Black wire as necessary and retest. If Black wire is okay, go to next step.
  3. Turn ignition on. Measure voltage between ground and Dark Blue/Light Green wire terminal of amplifier connector. If battery voltage is present, go to next step. If battery voltage is not present, check cruise control fuse and circuit. Repair or replace as necessary.
  4. Step on brake pedal. Measure voltage at Light Green wire terminal of amplifier connector. If stoplights illuminate and battery voltage is present, go step 6). If stoplights illuminate and battery voltage is not present, go to next step.
  5. Check continuity between stoplight switch and amplifier. If continuity exists, replace amplifier and retest. If continuity does not exists, repair wiring between stoplight switch and amplifier as necessary.
  6. Measure voltage between ground and Light Blue/Black wire terminal of steering wheel control switch 4-pin connector. If 7.8 volts is present, go to step 9). If 7.8 volts is not present, go to next step.
  7. Measure voltage between ground and Dark Blue/Light Green wire terminal of amplifier connector. If zero volts is present, go to step 8). If battery voltage is present, check if ON button is sticking. If ON button is okay, replace amplifier and retest. If ON button is not okay, repair or replace ON button as necessary.
  8. Check for a short to ground in Light Blue/Black wire between amplifier and steering column brush assembly. If a short circuit exists, repair wiring as necessary. If a short circuit does not exist, replace amplifier and retest.
  9. Connect positive voltmeter lead to Light Blue/Black wire terminal of amplifier connector and negative voltmeter lead to Black wire terminal of amplifier connector. Measure voltage while turning steering wheel 1/4 turn left and right with specified control switch pressed. See CONTROL SWITCH VOLTAGE table.
    CONTROL SWITCH VOLTAGE

    Switch Position Approx. Voltage (Volts)
    No Button Pressed 7.8
    ON 12.0
    OFF 0
    RESUME (RSM) 6.5
    SET/ACCEL 4.5
    COAST (CST) 1.5
  10. If voltages are as specified, go to step 16). If voltages are not as specified, turn ignition off. Disconnect amplifier 6-pin connector. Connect positive lead of ohmmeter to Light Blue/Black wire terminal of amplifier connector and negative lead to Black wire terminal of amplifier connector. Measure resistance while turning steering wheel 1/4 turn left and right with specified control switch pressed. See CONTROL SWITCH RESISTANCE table.
    CONTROL SWITCH RESISTANCE

    Switch Position Ohms
    OFF 0-1
    SET/ACCEL 646-714
    COAST (CST) 114-126
    RESUME (RSM) 2090-2310
  11. If resistances are as specified, replace amplifier and go to step 9). If resistances are not as specified, remove horn pad (or air bag if equipped). Disconnect steering wheel control switch 4-pin connector. Connect positive lead of ohmmeter to Light Blue/Black wire terminal of control switch connector and negative lead to Yellow/Light Green wire terminal of control switch connector. Measure resistance. If resistance measures 0-1 ohm, go to next step. If resistance does not measure 0-1 ohm, replace control switch assembly.
  12. Connect positive lead of ohmmeter to Light Blue/Black wire terminal of control switch connector and negative lead to Black wire terminal of control switch connector. Measure resistance with specified control switch pressed. See CONTROL SWITCH RESISTANCE table. If resistances are as specified, go to next step. If resistances are not as specified, replace control switch assembly.
  13. Remove steering wheel. Check continuity between Light Blue/Black wire and Black wire terminals of amplifier 6-pin connector and steering column brush assembly. If continuity does not exist, go to next step. If continuity exists, go to step 15).
  14. Check continuity between steering column brush assembly 3-pin connector and brush assembly. Also check continuity between steering column brush assembly 3-pin connector and amplifier 6-pin connector. Repair wiring or replace brush assembly as required.
  15. Clean brush assembly and slip rings with solvent, then lubricate with cruise control slip ring grease. Reinstall steering wheel and horn pad (or air bag if equipped), then go to step 2).
  16. Connect ohmmeter between Gray/Black wire terminal and Pink/Orange wire terminal of amplifier 6-pin connector. Measure resistance. If resistance does not measure 180-250 ohms, go to next step. If resistance measures 180-250 ohms, wiring is okay.
    NOTE: Not all speed sensor problems can be detected with resistance checks. Substitution with a known good speed sensor may be necessary.
  17. Check continuity between Gray/Black wire terminal of amplifier connector and Gray/Black wire terminal of speed sensor 2-pin connector. If continuity does not exist, repair wiring as necessary. If continuity exists, check speed sensor. See SPEED SENSOR TEST.
About FixVault