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Automatic Transmission Shift Interlock System: Diagnosis Nissan Altima L30 рестайлинг

Automatic Trans 9 illustrations ~3793 words

Diagnostic Procedure (Symptoms No. 1 & 2)

  1. Check key interlock cable for damage. Repair as necessary. See «KEY INTERLOCK CABLE»(ref-126043-S28081067102001101900000) under REMOVAL & INSTALLATION. If key interlock cable is okay, go to next step.
  2. Check Park/Neutral Position (PNP) switch and control cable adjustment. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Adjust as necessary. If okay, go to next step.
  3. Turn ignition on, engine off. Measure voltage between ASCD brake switch harness connector terminal No. 2 and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check the following items and repair as necessary: Check for open or short between ASCD brake switch harness connector terminal No. 2 and battery. Check for blown fuse No. 8 (10-amp). Inspect ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
  4. Turn ignition on, engine off. Measure voltage between A/T device harness connector terminal No. 5 and ground while applying and releasing brake pedal. No voltage should exist when brake pedal is depressed and battery voltage should exist when brake pedal is released. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between A/T device harness connector terminal No. 5 and ASCD brake switch harness connector terminal No. 1. Check ASCD brake switch. See «ASCD BRAKE SWITCH»(ref-126043-S23023653592001101900000) under COMPONENT TESTS.
  5. Turn ignition off. Disconnect A/T device harness connector. Check for continuity between A/T device harness connector terminal No. 6 and ground. If continuity exists, go to next step. If continuity does not exist, repair open in wire between A/T device harness connector terminal No. 6 and ground.
  6. Check park position switch. See «PARK POSITION SWITCH»(ref-126043-S38034067902001101900000) under COMPONENT TESTS. Replace as necessary. If park position switch is okay, go to next step.
  7. Check shift lock solenoid. See «SHIFT LOCK SOLENOID»(ref-126043-S05880724102001101900000) under COMPONENT TESTS. Replace as necessary. If shift lock solenoid is okay, go to next step.
  8. Reconnect park position switch and shift lock solenoid harness connector. Turn ignition on. Check shift lock system operation. If system is not functioning properly, recheck harness connections.

Scheme 92

Scheme 92
Scheme 92
  1. Check key interlock cable for damage. Repair as necessary. See «KEY INTERLOCK CABLE»(ref-126043-S28081067102001101900000) under REMOVAL & INSTALLATION. If key interlock cable is okay, go to next step.
  2. Check Park/Neutral Position (PNP) switch and control cable adjustment. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Adjust as necessary. If okay, go to next step.
  3. Turn ignition on, engine off. Measure voltage between ASCD brake switch harness connector terminal No. 1 and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check the following items and repair as necessary: Check for open or short between ASCD brake switch harness connector terminal No. 1 and battery. Check for blown fuse No. 5 (7.5-amp). Inspect ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
  4. Turn ignition on, engine off. Measure voltage between A/T device harness connector terminal No. 2 and ground while applying and releasing brake pedal. No voltage should exist when brake pedal is depressed and battery voltage should exist when brake pedal is released. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between A/T device harness connector terminal No. 2 and ASCD brake switch harness connector terminal No. 2. Check ASCD brake switch. See «ASCD BRAKE SWITCH»(ref-126043-S23023653592001101900000) under COMPONENT TESTS.
  5. Turn ignition off. Disconnect A/T device harness connector. Check for continuity between A/T device harness connector terminal No. 1 and ground. If continuity exists, go to next step. If continuity does not exist, repair open in wire between A/T device harness connector terminal No. 1 and ground.
  6. Check park position switch. See «PARK POSITION SWITCH»(ref-126043-S38034067902001101900000) under COMPONENT TESTS. Replace as necessary. If park position switch is okay, go to next step.
  7. Check shift lock solenoid. See «SHIFT LOCK SOLENOID»(ref-126043-S05880724102001101900000) under COMPONENT TESTS. Replace as necessary. If shift lock solenoid is okay, go to next step.
  8. Reconnect park position switch and shift lock solenoid harness connector. Turn ignition on. Check shift lock system operation. If system is not functioning properly, recheck harness connections.

Scheme 93

Scheme 93
Scheme 93
  1. Check key interlock cable for damage. Repair as necessary. See «KEY INTERLOCK CABLE»(ref-126043-S28081067102001101900000) under REMOVAL & INSTALLATION. If key interlock cable is okay, go to next step.
  2. Check Park/Neutral Position (PNP) switch and control cable adjustment. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Adjust as necessary. If okay, go to next step.
  3. Turn ignition on, engine off. Measure voltage between stoplight switch harness connector terminal No. 1 and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check the following items and repair as necessary: Check for open or short in wire between stoplight switch harness connector terminal No. 1 and battery. On G20, check for blown fuse No. 14 (15-amp) and on Sentra, check for blown fuse No. 2 (10-amp). Check ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
  4. Turn ignition on, engine off. Measure voltage between A/T device harness connector terminal No. 7 and ground while applying and releasing brake pedal. Battery voltage should exist when brake pedal is depressed and no voltage should exist when brake pedal is released. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between stoplight switch harness connector terminal No. 1 and battery. Check for open or short in wire between A/T device harness connector terminal No. 7 and stoplight switch harness connector terminal No. 1. On G20, check for blown fuse No. 14 (15-amp) and on Sentra, check for blown fuse No. 2 (10-amp). Check stoplight switch. See «STOPLIGHT SWITCH»(ref-126043-S07106887602001102200000) under COMPONENT TESTS.
  5. Turn ignition off. Check for open, short to ground or short to voltage in wire between A/T device harness connector terminal No. 6 and ground. If okay, go to next step. If open or short is found in wire, repair as necessary.
  6. Turn ignition on. Place selector lever in "P" position and depress brake pedal. Measure voltage between A/T device harness connector terminals No. 6 and 7. Battery voltage should exist. Measure voltage between A/T device harness connector terminals No. 5 and 6. Battery voltage should exist. If voltage is as specified, shift lock relay is okay. Go to next step. If voltage is not as specified, replace A/T device.
  7. Check park position switch. See «PARK POSITION SWITCH»(ref-126043-S38034067902001101900000) under COMPONENT TESTS. Replace as necessary. If park position switch is okay, go to next step.
  8. Check shift lock solenoid. See «SHIFT LOCK SOLENOID»(ref-126043-S05880724102001101900000) under COMPONENT TESTS. Replace as necessary. If shift lock solenoid is okay, go to next step.
  9. Reconnect park position switch and shift lock solenoid harness connector. Turn ignition on, engine off. Check shift lock system operation. If system is not functioning properly, recheck harness connections.

Scheme 94

Scheme 94
Scheme 94
  1. Check key interlock cable for damage. Repair as necessary. See «KEY INTERLOCK CABLE»(ref-126043-S28081067102001101900000) under REMOVAL & INSTALLATION. If key interlock cable is okay, go to next step.
  2. Check Park/Neutral Position (PNP) switch and control cable adjustment. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Adjust as necessary. If okay, go to next step.
  3. Turn ignition on, engine off. Measure voltage between A/T device harness connector terminal No. 5 and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check the following items and repair as necessary: Check for open or short in wire between A/T device harness connector terminal No. 5 and ignition switch. Check for blown fuse No. 30 (10-amp). Check ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
  4. Turn ignition off. Measure voltage between A/T device harness connector terminal No. 7 and ground while applying and releasing brake pedal. No voltage should exist when brake pedal is depressed and battery voltage should exist when brake pedal is released. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between stoplight switch harness connector terminal No. 2 and battery. Check for open or short in wire between A/T device harness connector terminal No. 7 and stoplight switch harness connector terminal No. 1. Check for blown fuse No. 2 (15-amp). Check stoplight switch. See «STOPLIGHT SWITCH»(ref-126043-S07106887602001102200000) under COMPONENT TESTS.
  5. Turn ignition off. Check for open, short to ground or short to voltage in wire between A/T device harness connector terminal No. 6 and ground. If okay, go to next step. If open or short is found in wire, repair as necessary.
  6. Turn ignition off. Place selector lever in "P" position and depress brake pedal. Measure resistance between shift lock relay harness connector terminals No. 1 and 2. About 100-125 ohms should exist. Check for continuity between shift lock relay harness connector terminals No. 3 and 5 with ignition on and brake pedal depressed. Continuity should exist. Check for continuity between shift lock relay harness connector terminals No. 3 and 5 with ignition off and brake pedal depressed. Continuity should not exist. If all test results are as specified, shift lock relay is okay. Go to next step. If all test results are not as specified, replace shift lock relay.
  7. Check park position switch. See «PARK POSITION SWITCH»(ref-126043-S38034067902001101900000) under COMPONENT TESTS. Replace as necessary. If park position switch is okay, go to next step.
  8. Check shift lock solenoid. See «SHIFT LOCK SOLENOID»(ref-126043-S05880724102001101900000) under COMPONENT TESTS. Replace as necessary. If shift lock solenoid is okay, go to next step.
  9. Reconnect park position switch and shift lock solenoid harness connector. Turn ignition on, engine off. Check shift lock system operation. If system is not functioning properly, recheck harness connections.

Scheme 95

Scheme 95
Scheme 95
  1. Check key interlock cable for damage. Repair as necessary. See «KEY INTERLOCK CABLE»(ref-126043-S28081067102001101900000) under REMOVAL & INSTALLATION. If key interlock cable is okay, go to next step.
  2. Check Park/Neutral Position (PNP) switch and control cable adjustment. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Adjust as necessary. If okay, go to next step.
  3. Turn ignition on, engine off. Measure voltage between ASCD brake switch harness connector terminal No. 1 and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check the following items and repair as necessary: Check for open or short between ASCD brake switch harness connector terminal No. 1 and battery. Check for blown fuse No. 11 (7.5-amp). Check ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
  4. Turn ignition on, engine off. Measure voltage between A/T device harness connector terminal No. 5 and ground while applying and releasing brake pedal. No voltage should exist when brake pedal is depressed and battery voltage should exist when brake pedal is released. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between A/T device harness connector terminal No. 5 and ASCD brake switch harness connector terminal No. 2. Check ASCD brake switch. See «ASCD BRAKE SWITCH»(ref-126043-S23023653592001101900000) under COMPONENT TESTS.
  5. Turn ignition off. Disconnect A/T device harness connector. Check for continuity between A/T device harness connector terminal No. 6 and ground. If continuity exists, go to next step. If continuity does not exist, repair open in wire between A/T device harness connector terminal No. 6 and ground.
  6. Check park position switch. See «PARK POSITION SWITCH»(ref-126043-S38034067902001101900000) under COMPONENT TESTS. Replace as necessary. If park position switch is okay, go to next step.
  7. Check shift lock solenoid. See «SHIFT LOCK SOLENOID»(ref-126043-S05880724102001101900000) under COMPONENT TESTS. Replace as necessary. If shift lock solenoid is okay, go to next step.
  8. Reconnect park position switch and shift lock solenoid harness connector. Turn ignition on. Check shift lock system operation. If system is not functioning properly, recheck harness connections.
  1. Check Park/Neutral Position (PNP) switch and control cable adjustment. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Adjust as necessary. If okay, go to next step.
  2. Turn ignition on, engine off. Measure voltage between ASCD brake switch harness connector terminal No. 1 and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check the following items and repair as necessary: Check for open or short between ASCD brake switch harness connector terminal No. 1 and battery. Check for blown fuse No. 29 (10-amp). Check ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
  3. Turn ignition on, engine off. Measure voltage between A/T device harness connector terminal No. 2 and ground while applying and releasing brake pedal. No voltage should exist when brake pedal is depressed and battery voltage should exist when brake pedal is released. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between A/T device harness connector terminal No. 2 and ASCD brake switch harness connector terminal No. 2. Check ASCD brake switch. See «ASCD BRAKE SWITCH»(ref-126043-S23023653592001101900000) under COMPONENT TESTS.
  4. Turn ignition off. Disconnect A/T device harness connector. Check for open, short to ground or short to voltage between A/T device harness connector terminal No. 1 and ground. If okay, go to next step. If open or short is found in wire, repair as necessary.
  5. Check park position switch. See «PARK POSITION SWITCH»(ref-126043-S38034067902001101900000) under COMPONENT TESTS. Replace as necessary. If park position switch is okay, go to next step.
  6. Check shift lock solenoid. See «SHIFT LOCK SOLENOID»(ref-126043-S05880724102001101900000) under COMPONENT TESTS. Replace as necessary. If shift lock solenoid is okay, go to next step.
  7. Reconnect park position switch and shift lock solenoid harness connector. Turn ignition on. Check shift lock system operation. If system is not functioning properly, recheck harness connections.

Scheme 96

Scheme 96
Scheme 96

Diagnostic Procedure (Symptom No. 1)

  1. Access Shift Lock Control Unit (SLCU). (Scheme 97) Ensure ignition is off. Measure voltage between SLCU harness connector terminal No. 1 and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check the following items and repair as necessary: Check for open or short in wire between battery and SLCU harness connector terminal No. 1. Check for blown fuse No. 26 (20-amp).
  2. Turn ignition off. Measure voltage between SLCU harness connector terminal No. 5 and ground with ignition off and on. No voltage should exist with ignition off, and battery voltage should exist with ignition on. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between battery and SLCU harness connector terminal No. 5. Check for blown fuse No. 17 (10-amp). Check ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
  3. Turn ignition off. Disconnect SLCU connector. Check for continuity between SLCU harness connector terminal No. 7 and ground. If continuity exists, go to next step. If continuity does not exist, repair open in wire or connector.
  4. Reconnect SLCU connector. Remove key from ignition switch. Access A/T device. (Scheme 98) Measure voltage between A/T device harness connector terminal No. 5 and ground. (Scheme 99) If no voltage exists, go to next step. If voltage exists, check key switch. See «KEY SWITCH»(ref-126043-S08428715282001101900000) under COMPONENT TESTS. Repair as necessary.
  5. Insert key into ignition switch. Measure voltage between A/T device harness connector terminal No. 5 and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check the following items and repair as necessary: Check for open or short in wire between A/T device harness connector terminal No. 5 and key lock switch harness connector terminal No. 4. Check for open or short in wire between key lock switch harness connector terminal No. 3 and fuse No. 28 (10-amp). Check key switch. See «KEY SWITCH»(ref-126043-S08428715282001101900000) under COMPONENT TESTS.
  6. Turn ignition on, engine off. Ensure selector lever is in "P" position and selector lever button is released. Measure voltage between SLCU harness connector terminal No. 4 and ground. If no voltage exists, go to next step. If voltage exists, check detention switch. See «DETENTION SWITCH»(ref-126043-S13731422422001101900000) under COMPONENT TESTS. Replace as necessary.
  7. Turn ignition on, engine off. With selector lever in "P" position, depress brake pedal. Push selector lever button. Measure voltage between SLCU harness connector terminal No. 4 and ground. Battery voltage should exist. Move selector lever to any other position. Battery voltage should continue to exist. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between SLCU harness connector terminal No. 4 and A/T device harness connector terminal No. 6. Check for open or short in wire between A/T device harness connector terminal No. 5 and key switch harness connector terminal No. 4. Check detention switch. See «DETENTION SWITCH»(ref-126043-S13731422422001101900000) under COMPONENT TESTS.
  8. Turn ignition off. Place selector lever in "P" position. Measure voltage between A/T device harness connector terminal No. 8 and ground while depressing and releasing brake pedal. With brake pedal depressed, battery voltage should exist. With brake pedal released, no voltage should exist. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between A/T harness connector terminal No. 8 and stoplight switch harness connector terminal No. 2. Check for open or short in wire between stoplight switch harness connector terminal No. 1 and fuse No. 37 (15-amp). Check stoplight switch. See «STOPLIGHT SWITCH»(ref-126043-S07106887602001102200000) under COMPONENT TESTS.
  9. Turn ignition on, engine off. Measure voltage between SLCU harness connector terminal No. 6 and ground while depressing and releasing brake pedal. With brake pedal depressed, battery voltage should exist. With brake pedal released, no voltage should exist. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between SLCU harness connector terminal No. 6 and A/T device harness connector terminal No. 9. Check shift lock solenoid. See «SHIFT LOCK SOLENOID»(ref-126043-S05880724102001101900000) under COMPONENT TESTS.
  10. Check shift lock system operation. If system is not functioning properly, perform control unit input/output signal test. See «SHIFT LOCK CONTROL UNIT»(ref-126043-S26613524902001101900000) under COMPONENT TESTS. Repair as necessary.

Diagnostic Procedure (Symptom No. 2)

  1. Access Shift Lock Control Unit (SLCU). (Scheme 97) Ensure ignition is off. Measure voltage between SLCU harness connector terminal No. 1 and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check the following items and repair as necessary: Check for open or short in wire between SLCU harness connector terminal No. 1 and fuse No. 26 (20-amp). Check for blown fuse No. 17 (10-amp).
  2. Turn ignition off. Measure voltage between SLCU harness connector terminal No. 5 and ground. No voltage should exist. Turn ignition on, engine off. Battery voltage should exist. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between SLCU harness connector terminal No. 5 and battery. Check for blown fuse No. 17 (10-amp). Check ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
  3. Turn ignition off. Disconnect SLCU harness connector. Check for continuity between SLCU harness connector terminal No. 7 and ground. If continuity exists, go to next step. If continuity does not exist, repair open in wire between SLCU harness connector terminal No. 7 and ground.
  4. Reconnect SLCU connector. Remove key from ignition switch. Access A/T device harness connector. (Scheme 98) Measure voltage between A/T device harness connector terminal No. 5 and ground. (Scheme 99) No voltage should exist. If voltage is as specified, go to next step. If voltage is not as specified, check key switch. See «KEY SWITCH»(ref-126043-S08428715282001101900000) under COMPONENT TESTS. Repair as necessary.
  5. Insert key into ignition switch. Measure voltage between A/T device harness connector terminal No. 5 and ground. Battery voltage should exist. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between A/T device harness connector terminal No. 5 and key switch harness connector terminal No. 4. Check for open or short in wire between key switch harness connector terminal No. 3 and fuse No. 28 (10-amp) in junction block fuse block. Check key switch. See «KEY SWITCH»(ref-126043-S08428715282001101900000) under COMPONENT TESTS.
  6. Turn ignition on, engine off. Ensure selector lever is in "P" position. Measure voltage between SLCU harness connector terminal No. 2 and ground. No voltage should exist. If voltage is as specified, go to next step. If voltage is not as specified, check detention switch. See «DETENTION SWITCH»(ref-126043-S13731422422001101900000) under COMPONENT TESTS. Replace as necessary.
  7. Turn ignition on, engine off. Measure voltage between SLCU harness connector terminal No. 2 and ground while depressing brake pedal and selector lever button. Battery voltage should exist. Move selector lever to any other position. Battery voltage should continue to exist. If voltage is as specified, go to next step. If voltage is not as specified, check the following items and repair as necessary: Check for open or short in wire between SLCU harness connector terminal No. 2 and A/T device harness connector terminal No. 7. Check for open or short in wire between A/T device harness connector terminal No. 5 and key switch harness connector terminal No. 4. Check detention switch. See «DETENTION SWITCH»(ref-126043-S13731422422001101900000) under COMPONENT TESTS.
  8. Place selector lever in "P" position and release selector button. Turn ignition off. Access key lock solenoid. (Scheme 100) Turn ignition on, engine off. Measure voltage between key lock solenoid harness connector terminal No. 2 and ground at the moment ignition is turned from off to on. Battery voltage should exist for about 0.1 second. If voltage is as specified, go to next step. If voltage is not as specified, check for open or short between key lock solenoid harness connector terminal No. 2 and SLCU harness connector terminal No. 8. Repair as necessary. If harness is okay, replace SLCU.
  9. Turn ignition off. Disconnect key lock solenoid harness connector. Check for continuity between key lock solenoid harness connector terminal No. 1 and ground. Continuity should exist. If continuity does not exist, repair open in wire between key lock solenoid harness connector terminal No. 1 and ground.

Scheme 97

Scheme 97
Scheme 97

Scheme 98

Scheme 98
Scheme 98

Scheme 99

Scheme 99
Scheme 99

Scheme 100

Scheme 100
Scheme 100

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