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Home >> Infiniti >> 1997 >> Q45 Base >> Repair and Diagnosis >> Body & Frame >> Body, Cab Control Systems >> Multiplex Control System >> Self-Diagnostic System >> Diagnostics Using Indicator Lights >> Mode I (LAN Communication)
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Mode I (LAN Communication)

  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). See LAN COMMUNICATION TROUBLE CODES  table.
  2. To enter on-board diagnostic Mode I, turn ignition off. Set headlight switch and rear window defogger switch in OFF position. Ensure all doors are closed. Set interior light switch in AUTO position. Set driver and passenger-side map light switches to OFF position. Place gear selector lever in Park.
  3. Turn ignition on. Return ignition switch to ACC position, then press rear window defogger switch more than 10 times in 10 seconds, ending in the OFF position. Self-diagnostic indicator lights (interior dome and step lights) should come on.
  4. Turn ignition switch to ON position when indicator lights come on. Indicator lights should come on for 2 seconds, then turn off for 2 seconds, indicating successful entry into self-diagnostic Mode I. Self-diagnostic indicator lights will now flash DTCs.
  5. The self-diagnostic lights will flash the first digit. A 1.5 second pause will separate the first and second digits of DTC, then second digit will be flashed. See Fig 1 .
  6. Record DTCs, and perform appropriate repair procedure. See DIAGNOSTIC TESTS  . To exit diagnostic mode, turn ignition off, or drive vehicle at greater than 4 MPH. Diagnostic mode is automatically canceled if left unattended for 10 minutes after DTCs are retrieved. To clear DTCs, turn ignition off and remove fuse No. 14 (7.5-amp), located in interior fuse block.
Fig 1: Reading DTCs Using Interior Lights
G96H06331Courtesy of NISSAN MOTOR CO., U.S.A.
LAN COMMUNICATION TROUBLE CODES

Trouble Codes LCU No. Failure Description
11 N/A N/A
24 01 Communication Fault
25 01 Data Line A-1 - No Response
34 02 Communication Fault
35 02 Data Line A-2 - No Response
41 03 Communication Fault
42 03 Data Line A-1 - No Response
44 04 Communication Fault
45 04 Data Line A-2 - No Response
47 05 Communication Fault
48 05 Data Line A-3 - No Response