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Test 3: ASCD Brake/Stoplight Switch Check

  1. Brake/Stoplight Switch Circuit Check (With Nissan's CONSULT Scan Tool)

    Using Nissan's CONSULT scan tool in DATA MONITOR mode, observe BRAKE SW on display. See SELF-DIAGNOSTIC MODES  . Place gear selector lever in "P" or "N" position. Depress brake pedal. BRAKE SW OFF should be displayed on scan tool. Release brake pedal. Place gear selector lever in any position other than"P" or "N". BRAKE SW ON should be displayed on scan tool. If scan tool display is as specified, go to step  4 . If scan tool display is not as specified, go to step  3 .

  2. Brake/Stoplight Switch Circuit Check (Without Nissan's CONSULT Scan Tool)

    Turn ignition switch to LOCK position. Disconnect ASCD control unit harness connector. Turn ignition switch to RUN position. Turn ASCD MAIN switch on. Measure voltage at ASCD control unit harness connector terminal No. 5 (Gray/Red wire). See Figure . With gear selector lever in "P" or "N" position and brake pedal depressed, zero volts should exist. With brake pedal released and gear selector lever not in "P" or "N", battery voltage should exist. If voltage readings are not as specified, go to next step. If voltage readings are as specified, go to step  5 .
  3. Check for a faulty ASCD brake switch or faulty Park Neutral Position (PNP) switch. See SWITCHES  under COMPONENT TESTS. Also check for a faulty PNP relay, faulty diodes, or an open or short in harness. See WIRING DIAGRAMS  . Repair as necessary.

  4. Check Stoplight Switch Circuit (With Nissan's CONSULT Scan Tool)

    Using Nissan's CONSULT scan tool in DATA MONITOR mode, observe STOP LAMP SW on display. Display should read ON with brake pedal depressed, and OFF with brake pedal released. If scan tool display is as specified, ASCD brake/stoplight switch is okay. If scan tool display is not as specified, go to step  6 .

  5. Check Stoplight Switch Circuit (Without Nissan's CONSULT Scan Tool)

    Turn ignition switch to LOCK position. Disconnect ASCD control unit harness connector. Turn ignition switch to RUN position. Measure voltage at terminal No. 11 (Red wire) at ASCD control unit harness connector. With brake pedal depressed, battery voltage should exist. Zero volts should exist with brake pedal released. If operation is as specified, ASCD brake/stoplight switch is okay. If operation is not as specified, go to next step.
  6. Check for faulty fuse No. 37 (15-amp) in instrument panel fuse box. Check for an open or short in harness between ASCD control unit and stoplight switch. Also check for a faulty stoplight switch. See SWITCHES  under COMPONENT TESTS. Repair as necessary.
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