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Multiplex Control System: Diagnosis Nissan Maxima A32

Body, Cab Control Systems 6 illustrations ~1573 words

SELF-DIAGNOSTIC SYSTEM

In-Vehicle Multiplexing System (IVMS) can be diagnosed using vehicle's on-board diagnostic functions or Nissan CONSULT.

DIAGNOSTICS USING INDICATOR LIGHTS

Note. The following procedure is used when Nissan CONSULT scan tool is not available.

Self-Diagnostic Indicator Lights

Interior dome light and step lights are used in on-board diagnostics to indicate system malfunctions. (Scheme 2) Depending on the on-board diagnostic mode, interior light(s) will either flash Diagnostic Trouble Codes (DTCs) or display some specific patterns to indicate the malfunctioning item.

Scheme 2

Scheme 2: Self-Diagnostic Indicator Lights
Scheme 2: Self-Diagnostic Indicator Lights

Mode I (Diagnostic Code Output)

  1. This mode checks the communication between the Body Control Module (BCM) and each Local Control Unit (LCU). If a malfunction is detected, self-diagnostic indicator lights (interior dome and step lights) will flash a 2-digit Diagnostic Trouble Code (DTC).
  2. To enter on-board diagnostic Mode I, turn ignition off. Set headlight switch and rear window defogger switch to OFF position. Ensure all doors are closed. Set interior light switch in center "O" position.
  3. Turn ignition on and then off. Repeatedly press rear defogger switch to ON position more than 10 times in 10 seconds, and then leave switch in the OFF position. Self-diagnostic indicator lights (dome and step lights) should come on. Turn ignition switch to ON position within 5 seconds after self-diagnostic indicator lights come on.
  4. Indicator lights should go off. Self-diagnostic indicator lights should come on for 2 seconds and then go off for 2 seconds, indicating successful entry to self-diagnostic Mode I. Self-diagnostic indicator lights will now flash DTCs.
  5. The self-diagnostic lights will flash the first digit. Then a one-second pause separates the first and second digits of DTC. Then second digit will be flashed. (Scheme 3)
  6. Record DTCs, and perform appropriate repair procedure. See «DIAGNOSTIC TESTS»(ref-32650-S08044194892001101500000). To exit diagnostic mode, turn ignition off. To clear diagnostic codes, remove fuse No. 56 (7.5-amp) located in fuse and fusible link box.

Scheme 3

Scheme 3
Scheme 3

DIAGNOSTICS USING NISSAN CONSULT

Note. Limited information on Nissan CONSULT is available. For additional information, refer to Nissan CONSULT operation manual.

Entering LAN System Diagnostics

Turn ignition off. Connect Nissan CONSULT to Data Link Connector (DLC). (Scheme 4) Turn ignition on. Touch START on Nissan CONSULT screen menu. To enter IVMS diagnostics, select IVMS from CONSULT menu. Read the CONSULT messages. Refer to the CONSULT MESSAGE TEST REFERENCE table. Perform the appropriate DTC test under DIAGNOSTIC TESTS.

Scheme 4

Scheme 4: Entering LAN System Diagnostics
Scheme 4: Entering LAN System Diagnostics

DTC 24: COMM. FAULT W/DRIVER'S DOOR CONTROL UNIT (LCU 01)

Erase DTCs and recheck for DTCs. If DTC 24 is retrieved again, replace LCU 01. If DTC 24 is not retrieved for a second time, fault is intermittent.

DTC 25: NO COMMUNICATION W/DRIVER'S DOOR CONTROL UNIT (LCU 01)

  1. Check Power Supply To LCU 01 - Check for poor connection at LCU 01. Repair as necessary. Disconnect LCU 01 harness connector. Turn ignition on. Measure voltage between terminal No. 13 at LCU 01 harness connector and ground. (Scheme 5) If battery voltage exists, go to next step. If battery voltage does not exist, repair open power supply circuit (White/Red wire) between fusible link and LCU 01 harness connector. See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  2. Check Ground Circuit To LCU 01 - Check for poor connection at LCU 01. Repair as necessary. Disconnect LCU 01 harness connector. Check continuity between ground and terminal No. 16 at LCU 01 harness connector. If continuity exists, go to next step. If continuity does not exist, repair open ground circuit (Black wire). See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  3. Check For Open Data Circuit - Check continuity between terminal No. 1 at LCU 01 harness connector and terminal No. 12 at BCM harness connector. (Scheme 6) If continuity does not exist, repair open data circuit (Red/Yellow wire) between BCM and LCU 01. If continuity exists, recheck for DTCs. If DTC 25 is retrieved again, replace LCU 01.

Scheme 5

Scheme 5
Scheme 5

Scheme 6

Scheme 6
Scheme 6

DTC 34: COMM. FAULT W/PASSENGER'S DOOR CONTROL UNIT (LCU 02)

Erase DTCs and recheck for DTCs. If DTC 34 is retrieved again, replace LCU 02. If DTC 34 is not retrieved for a second time, fault is intermittent.

DTC 35: NO COMM. W/PASSENGER'S DOOR CONTROL UNIT (LCU 02)

  1. Check Power Supply To LCU 02 - Check for poor connection at LCU 02. Repair as necessary. Disconnect LCU 02 harness connector. Turn ignition on. Measure voltage between terminal No. 13 at LCU 02 harness connector and ground. (Scheme 5) If battery voltage exists, go to next step. If battery voltage does not exist, repair open power supply circuit (White/Red wire) between fusible link and LCU 02 harness connector. See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  2. Check Ground Circuit To LCU 02 - Check for poor connection at LCU 02. Repair as necessary. Disconnect LCU 02 harness connector. Check continuity between ground and terminal No. 16 at LCU 02 harness connector. If continuity exists, go to next step. If continuity does not exist, repair open ground circuit (Black wire). See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  3. Check For Open Data Circuit - Check continuity between terminal No. 1 at LCU 02 harness connector and terminal No. 11 at BCM harness connector. (Scheme 6) If continuity does not exist, repair open data circuit (Red/Black wire) between BCM and LCU 02. If continuity exists, recheck for DTCs. If DTC 35 is retrieved again, replace LCU 02.

DTC 41: COMM. FAULT W/RIGHT REAR DOOR CONTROL UNIT (LCU 03)

Erase DTCs and recheck for DTCs. If DTC 41 is retrieved again, replace LCU 03. If DTC 41 is not retrieved for a second time, fault is intermittent.

DTC 42: NO COMM. W/RIGHT REAR DOOR CONTROL UNIT (LCU 03)

  1. Check Power Supply To LCU 03 - Check for poor connection at LCU 03. Repair as necessary. Disconnect LCU 03 harness connector. Turn ignition on. Measure voltage between terminal No. 17 at LCU 03 harness connector and ground. (Scheme 5) If battery voltage exists, go to next step. If battery voltage does not exist, repair open power supply circuit (White/Red wire) between fusible link and LCU 03 harness connector. See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  2. Check Ground Circuit To LCU 03 - Check for poor connection at LCU 03. Repair as necessary. Disconnect LCU 03 harness connector. Check continuity between ground and terminal No. 12 at LCU 03 harness connector. If continuity exists, go to next step. If continuity does not exist, repair open ground circuit (Black wire). See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  3. Check For Open Data Circuit - Check continuity between terminal No. 1 at LCU 03 harness connector and terminal No. 11 at BCM harness connector. (Scheme 6) If continuity does not exist, repair open data circuit (Red/Black wire) between BCM and LCU 03. If continuity exists, recheck for DTCs. If DTC 42 is retrieved again, replace LCU 03.

DTC 44: COMM. FAULT W/LEFT REAR DOOR CONTROL UNIT (LCU 04)

Erase DTCs and recheck for DTCs. If DTC 44 is retrieved again, replace LCU 04. If DTC 44 is not retrieved for a second time, fault is intermittent.

DTC 45: NO COMM. W/LEFT REAR DOOR CONTROL UNIT (LCU 04)

  1. Check Power Supply To LCU 04 - Check for poor connection at LCU 04. Repair as necessary. Disconnect LCU 04 harness connector. Turn ignition on. Measure voltage between terminal No. 17 at LCU 04 harness connector and ground. (Scheme 5) If battery voltage exists, go to next step. If battery voltage does not exist, repair open power supply circuit (White/Red wire) between fusible link and LCU 04 harness connector. See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  2. Check Ground Circuit To LCU 04 - Check for poor connection at LCU 04. Repair as necessary. Disconnect LCU 04 harness connector. Check continuity between ground and terminal No. 12 at LCU 04 harness connector. If continuity exists, go to next step. If continuity does not exist, repair open ground circuit (Black wire). See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  3. Check For Open Data Circuit - Check continuity between terminal No. 1 at LCU 04 harness connector and terminal No. 12 at BCM harness connector. (Scheme 6) If continuity does not exist, repair open data circuit (Red/Yellow wire) between BCM and LCU 04. If continuity exists, recheck for DTCs. If DTC 45 is retrieved again, replace LCU 04.

DTC 54: COMM. FAULT W/MULTI-REMOTE CONTROL UNIT (LCU 05)

Erase DTCs and recheck for DTCs. If DTC 54 is retrieved again, replace LCU 05. If DTC 54 is not retrieved for a second time, fault is intermittent.

DTC 55: NO COMM. W/MULTI-REMOTE CONTROL UNIT (LCU 05)

  1. Check Power Supply To LCU 05 - Check for poor connection at LCU 05. Repair as necessary. Disconnect LCU 05 harness connector. Turn ignition on. Measure voltage between terminal No. 2 at LCU 05 harness connector and ground. (Scheme 7) If battery voltage exists, go to next step. If battery voltage does not exist, repair open power supply circuit (Pink wire) between fusible link and LCU 05 harness connector. See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  2. Check Ground Circuit To LCU 05 - Check for poor connection at LCU 05. Repair as necessary. Disconnect LCU 05 harness connector. Check continuity between ground and terminal No. 4 at LCU 05 harness connector. (Scheme 7) If continuity exists, go to next step. If continuity does not exist, repair open ground circuit (Black wire). See «WIRING DIAGRAMS»(ref-32650-S12063338082001101500000).
  3. Check For Open Data Circuit - Check continuity between terminal No. 1 at LCU 05 harness connector and terminal No. 12 at BCM harness connector. (Scheme 6) If continuity does not exist, repair open data circuit (Red/Yellow wire) between BCM and LCU 05. If continuity exists, recheck for DTCs. If DTC 55 is retrieved again, replace LCU 05.

Scheme 7

Scheme 7
Scheme 7

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