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Body Control Modules: Diagnosis Nissan Altima L31

Body, Cab Control Systems 6 illustrations ~2982 words

CAN COMMUNICATION INSPECTION USING CONSULT-II

  1. Self-Diagnostic result check. Connect CONSULT-II to DLC, and select "BCM" on "SELECT SYSTEM" screen. Select "BCM Control Unit" on "SELECT WORK ITEM" screen, and select "SELF-DIAG RESULTS". Check display content in self-diagnostic results. If CONSULT-II displays ECM DTC U1000, go to next step and diagnose CAN COMM, CAN CIRC 1, CAN CIRC 2, CAN CIRC 3 and CAN CIRC 4. If CONSULT-II does not display ECM DTC U1000, no malfunction exists, testing is complete.
  2. Symptom check. Select "CAN Diagnosis Support Monitor" in data monitor. Select "START" and check display content. (Scheme 2) Print out monitor items and see «CAN SYSTEM»(ref-152300) article.

Scheme 2

Scheme 2
Scheme 2

COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS

Note. Before performing combination switch inspection according to self-diagnostic results, perform SYSTEM TESTS .

Connect to CONSULT-II, and select "BCM" on "SELECT SYSTEM" screen. Select "BCM CONTROL UNIT" on "SELECT WORK ITEM" screen, and select "SELF-DIAG RESULTS". Check display content in self-diagnostic results. For DTCs on display. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .

DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTCDescription
B2049OPEN DETECT 1: Front Wiper HI Intermittent Control 1 & 2 Cannot Be Input
B2050OPEN DETECT 2: Front Washer Intermittent Control 3 Cannot Be Input
B2051OPEN DETECT 3: Front Wiper LO, Front Wiper INT & Auto Light Cannot Be Input
B2052OPEN DETECT 4: TURN LH, PASSING, Headlight 2 & Front Fog Lamp Cannot Be Input
B2053OPEN DETECT 5: TURN RH, Headlight 1, HI BEAM & Lighting Switch 1st Position Cannot Be Input
B2054HEADLIGHT 1 SW NG: Headlight 1 Malfunction
B2055HEADLIGHT 2 SW NG: Headlight 2 Malfunction

DIAGNOSTIC TROUBLE CODE DEFINITIONS

DIAGNOSTIC TESTS

Note. Before performing diagnostic tests, see COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS .

Diagnostic Procedure

  1. Harness inspection. Turn ignition switch "OFF". Disconnect BCM connector (M19) and combination switch connector (M28). Check harness side continuity between BCM connector (M19), terminal No. 48 (Green/White) input 1 wire and combination switch connector (M28), terminal No. 1 (Green/White) input wire and between BCM connector (M19), terminal No. 47 (Red/White) output 1 wire and combination switch connector (M28), terminal No. 6 (Red/White) output wire. see scheme 25and see scheme 26. If continuity exists, go to next step. If continuity does not exist, check harness between BCM and combination switch for open or short circuit. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition switch "ON". Check voltage of BCM connector (M19), terminal No. 48 (Green/White) input 1 wire, harness side. If voltage is greater than 4.5 volts, go to next step. If voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. BCM output terminal inspection. Connect combination switch connector. Turn ignition switch "ON". Check BCM connector (M19), terminal No. 47 (Red/White) output 1 wire, harness side, voltage waveform. (Scheme 3) If voltage waveform is OK, there is a combination switch malfunction, go to next step. If voltage waveform is not OK, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  4. Combination switch inspection. Replace wiper switch. Confirm self-diagnostic results again, see «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If combination switch is OK, inspection is complete. If combination switch is not OK, confirm symptom again. See «SYSTEM TESTS»(ref-152221-S13256149592003012200000).

Scheme 3

Scheme 3
Scheme 3
  1. Harness inspection. Turn ignition switch "OFF". Disconnect BCM connector and combination switch connector. Check harness side continuity between BCM harness connector (M19), terminal No. 49 (Green/Black) input 2 wire and combination switch connector (M28), terminal No. 2 (Green/Black) input 2 wire and between BCM harness connector (M19), terminal No. 40 (Red/Black) output 2 wire and combination switch connector (M28), terminal No. 7 (Red/Black) output 2 wire. see scheme 25and see scheme 26. If continuity exists, go to next step. If continuity does not exist, check harness between BCM and combination switch for open or short circuit. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition switch "ON". Check voltage of BCM connector (M19), terminal No. 49 (Green/Black) input 2 wire, harness side. If voltage is greater than 4.5 volts, go to next step. If voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. BCM output terminal inspection. Connect combination switch connector. Turn ignition switch "ON". Check BCM connector (M19), terminal No. 40 (Red/Black) output 2 wire, harness side, voltage waveform. (Scheme 3) If voltage waveform is OK, there is a combination switch malfunction, go to next step. If voltage waveform is not OK, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  4. Combination switch inspection. Replace wiper switch. Confirm self-diagnostic results again, see «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If combination switch is OK, inspection is complete. If combination switch is not OK, confirm symptom again. See «SYSTEM TESTS»(ref-152221-S13256149592003012200000).
  1. Harness inspection. Turn ignition switch "OFF". Disconnect BCM connector and combination switch connector. Check harness side continuity between BCM harness connector (M19), terminal No. 50 (Green/Red) input 3 wire and combination switch connector (M28), terminal No. 3 (Green/Red) input 3 wire and between BCM harness connector (M19), terminal No. 41 (Red/Green) output 3 wire and combination switch connector (M28), terminal No. 10 (Red/Green) output 3 wire. see scheme 25and see scheme 26. If continuity exists, go to next step. If continuity does not exist, check harness between BCM and combination switch for open or short circuit. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition switch "ON". Check voltage of BCM connector (M19), terminal No. 50 (Green/Red) input 3 wire, harness side. If voltage is greater than 4.5 volts, go to next step. If voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. BCM output terminal inspection. Connect combination switch connector. Turn ignition switch "ON". Check BCM connector (M19), terminal No. 41 (Red/Green) output 3 wire, harness side, voltage waveform. (Scheme 3) If voltage waveform is OK, there is a combination switch malfunction, go to next step. If voltage waveform is not OK, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  4. Combination switch inspection. Replace combination switch. Confirm self-diagnostic results again, see «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If combination switch is OK, inspection is complete. If combination switch is not OK, replace wiper switch. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000). Confirm symptom again. If combination switch is OK, inspection is complete. If combination switch is not OK, replace switch base. Confirm self-diagnostic results again. If combination switch is OK, inspection is complete. If combination switch is not OK, confirm symptom again. See «SYSTEM TESTS»(ref-152221-S13256149592003012200000).
  1. Harness inspection. Turn ignition switch "OFF". Disconnect BCM connector and combination switch connector. Check harness side continuity between BCM harness connector (M19), terminal No. 51 (Green/Yellow) input 4 wire and combination switch connector (M28), terminal No. 4 (Green/Yellow) input 4 wire and between BCM harness connector (M19), terminal No. 42 (Red/Yellow) output 4 wire and combination switch connector (M28), terminal No. 9 (Red/Yellow) output 4 wire. see scheme 25and see scheme 26. If continuity exists, go to next step. If continuity does not exist, check harness between BCM and combination switch for open or short circuit. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition switch "ON". Check voltage of BCM connector (M19), terminal No. 51 (Green/Yellow) input 4 wire, harness side. If voltage is greater than 4.5 volts, go to next step. If voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. BCM output terminal inspection. Connect combination switch connector. Turn ignition switch "ON". Check BCM connector (M19), terminal No. 42 (Red/Yellow) output 4 wire, harness side, voltage waveform. (Scheme 3) If voltage waveform is OK, there is a combination switch malfunction, go to next step. If voltage waveform is not OK, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  4. Combination switch inspection. Replace combination switch. Confirm self-diagnostic results again, see «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If combination switch is OK, inspection is complete. If combination switch is not OK, replace wiper switch. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000). Confirm symptom again. If combination switch is OK, inspection is complete. If combination switch is not OK, replace switch base. Confirm self-diagnostic results again. If combination switch is OK, inspection is complete. If combination switch is not OK, confirm symptom again. See «SYSTEM TESTS»(ref-152221-S13256149592003012200000).
  1. Harness inspection. Turn ignition switch "OFF". Disconnect BCM connector and combination switch connector. Check harness side continuity between BCM harness connector (M19), terminal No. 52 (Blue/White) input 5 wire and combination switch connector (M28), terminal No. 5 (Blue/White) input 5 wire and between BCM harness connector (M19), terminal No. 43 (Blue) output 5 wire and combination switch connector (M28), terminal No. 8 (Blue) output 5 wire. see scheme 25and see scheme 26. If continuity exists, go to next step. If continuity does not exist, check harness between BCM and combination switch for open or short circuit. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition switch "ON". Check voltage of BCM connector (M19), terminal No. 52 (Blue/White) input 5 wire, harness side. If voltage is greater than 4.5 volts, go to next step. If voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. BCM output terminal inspection. Connect combination switch connector. Turn ignition switch "ON". Check BCM connector (M19), terminal No. 43 (Blue) output 5 wire, harness side, voltage waveform. (Scheme 3) If voltage waveform is OK, there is a combination switch malfunction, go to next step. If voltage waveform is not OK, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  4. Combination switch inspection. Replace combination switch. Confirm self-diagnostic results again, see «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If combination switch is OK, inspection is complete. If combination switch is not OK, replace wiper switch. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000). Confirm symptom again. If combination switch is OK, inspection is complete. If combination switch is not OK, replace switch base. Confirm self-diagnostic results again. If combination switch is OK, inspection is complete. If combination switch is not OK, confirm symptom again. See «SYSTEM TESTS»(ref-152221-S13256149592003012200000).

If this diagnostic DTC is set, replace headlight switch. See REMOVAL & INSTALLATION .

If this diagnostic DTC is set, replace Headlight switch. See REMOVAL & INSTALLATION .

DTC Confirmation Test

Turn ignition on and wait at least 3 seconds. Select DATA MONITOR mode with scan tool. If 1st trip DTC is detected, go to DIAGNOSTIC PROCEDURE . If 1st trip DTC is not detected, system is okay at this time.

Turn ignition "ON". Select CAN COMM SIGNALS in DATA MONITOR mode with scan tool. If OK is displayed for CAN COMM, CAN CIRC 1, CAN CIRC 2 (A/T models only), CAN CIRC 3 (models with TCS only), CAN CIRC 4, CAN CIRC 6 and CAN CIRC 7, system is okay. If OK is not displayed for these circuits, repair communication problem. See appropriate CAN SYSTEM article.

Symptom

With ignition "ON" left and right turn signal lamp are on and front wipers are on (LO speed).

  1. Harness inspection. Turn ignition "OFF". Disconnect BCM connector and combination switch connector. Check continuity between BCM harness connector (M19), terminal No. 48 (Green/White) input 1 wire and terminal No. 47 (Red/White) output 1 wire, harness side, and body ground. see scheme 25 If continuity exists, check harness between BCM and combination switch for short circuit. If continuity does not exist, go to next step. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition "ON". Check voltage between BCM connector (M19), terminal No. 48 (Green/White) input wire, harness side, and body ground. If the voltage is 4.5 volts or greater, there is a combination switch malfunction, go to next step. If the voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. Combination switch inspection. Replace lighting switch. Reconfirm self-diagnostic results. See «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If OK, inspection is complete. If not OK, replace wiper switch. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000). Reconfirm self-diagnostics results. If OK, inspection is complete. If not OK, replace switch base. Reconfirm self-diagnostic results. If OK, inspection is complete. If not OK, reconfirm symptom. See «SYMPTOM INDEX»(ref-152221-S12956015662003012200000) table.

With ignition switch "ON", headlights are "ON" (HI and LO) and front wiper "ON" (HI speed). With ignition "OFF", headlights are "ON" (HI and LO).

  1. Harness inspection. Turn ignition "OFF". Disconnect BCM connector and combination switch connector. Check continuity between BCM harness connector (M19), terminal No. 49 (Green/Black) input 2 wire and terminal No. 40 (Red/Black) output 2 wire, harness side, and body ground. see scheme 25 If continuity exists, check harness between BCM and combination switch for short circuit. If continuity does not exist, go to next step. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition "ON". Check voltage between BCM connector (M19), terminal No. 49 (Green/Black) input wire, harness side, and body ground. If the voltage is 4.5 volts or greater, there is a combination switch malfunction, go to next step. If the voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. Combination switch inspection. Replace lighting switch. Reconfirm self-diagnostic results. See «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If OK, inspection is complete. If not OK, replace wiper switch. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000). Reconfirm self-diagnostics results. If OK, inspection is complete. If not OK, replace switch base. Reconfirm self-diagnostic results. If OK, inspection is complete. If not OK, reconfirm symptom. See «SYMPTOM INDEX»(ref-152221-S12956015662003012200000) table.

With ignition "ON", headlights are on (HI and LO). With ignition "OFF" headlights are on (HI and LO).

  1. Harness inspection. Turn ignition "OFF". Disconnect BCM connector and combination switch connector. Check continuity between BCM harness connector (M19), terminal No. 50 (Green/Red) input 3 wire and terminal No. 41 (Red/Green) output 3 wire, harness side, and body ground. see scheme 25 If continuity exists, check harness between BCM and combination switch for short circuit. If continuity does not exist, go to next step. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition "ON". Check voltage between BCM connector (M19), terminal No. 50 (Green/Red) input wire, harness side, and body ground. If the voltage is 4.5 volts or greater, there is a combination switch malfunction, go to next step. If the voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. Combination switch inspection. Replace lighting switch. Reconfirm self-diagnostic results. See «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If OK, inspection is complete. If not OK, replace wiper switch. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000). Reconfirm self-diagnostics results. If OK, inspection is complete. If not OK, replace switch base. Reconfirm self-diagnostic results. If OK, inspection is complete. If not OK, reconfirm symptom. See «SYMPTOM INDEX»(ref-152221-S12956015662003012200000) table.

With ignition switch "ON", parking lamp and tail lamp are on and headlights are on at certain degrees of brightness. With ignition switch "OFF", parking lamp and tail lamp are on.

  1. Harness inspection. Turn ignition "OFF". Disconnect BCM connector and combination switch connector. Check continuity between BCM harness connector (M19), terminal No. 51 (Green/Yellow) input 4 wire and terminal No. 42 (Red/Yellow) output 4 wire, harness side, and body ground. see scheme 25 If continuity exists, check harness between BCM and combination switch for short circuit. If continuity does not exist, go to next step. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition "ON". Check voltage between BCM connector (M19), terminal No. 51 (Green/Yellow) input wire, harness side, and body ground. If the voltage is 4.5 volts or greater, there is a combination switch malfunction, go to next step. If the voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. Combination switch inspection. Replace lighting switch. Reconfirm self-diagnostic results. See «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If OK, inspection is complete. If not OK, replace wiper switch. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000). Reconfirm self-diagnostics results. If OK, inspection is complete. If not OK, replace switch base. Reconfirm self-diagnostic results. If OK, inspection is complete. If not OK, reconfirm symptom. See «SYMPTOM INDEX»(ref-152221-S12956015662003012200000) table.

With ignition switch "ON", front fog lamps are on. With ignition switch "OFF", front fog lamps are on.

  1. Harness inspection. Turn ignition "OFF". Disconnect BCM connector and combination switch connector. Check continuity between BCM harness connector (M19), terminal No. 52 (Blue/White) input 5 wire and terminal No. 43 (Blue) output 5 wire, harness side, and body ground. see scheme 25 If continuity exists, check harness between BCM and combination switch for short circuit. If continuity does not exist, go to next step. See «EXTERIOR LIGHTS»(ref-151282-S03267544812002121200000) in 2002 SYSTEM WIRING DIAGRAMS NISSAN - ALTIMA article.
  2. Inspection of BCM input terminal voltage. Connect BCM connector. Turn ignition "ON". Check voltage between BCM connector (M19), terminal No. 52 (Blue/White) input wire, harness side, and body ground. If the voltage is 4.5 volts or greater, there is a combination switch malfunction, go to next step. If the voltage is not greater than 4.5 volts, replace BCM. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000).
  3. Combination switch inspection. Replace lighting switch. Reconfirm self-diagnostic results. See «COMBINATION SWITCH INSPECTION ACCORDING TO SELF-DIAGNOSTIC RESULTS»(ref-152221-S32871704772003012300000). If OK, inspection is complete. If not OK, replace wiper switch. See «REMOVAL & INSTALLATION»(ref-152221-S36424314092003012200000). Reconfirm self-diagnostics results. If OK, inspection is complete. If not OK, replace switch base. Reconfirm self-diagnostic results. If OK, inspection is complete. If not OK, reconfirm symptom. See «SYMPTOM INDEX»(ref-152221-S12956015662003012200000) table.

INSPECTION OF BCM POWER SUPPLY & GROUND CIRCUIT

  1. Fuse and fusible link inspection. Check if any of the BCM fuses and/or fusible links are blown. See «FUSE & FUSIBLE LINK INSPECTION»(ref-152221-S30407555702003012500000) table.
  2. Power supply circuit inspection. Disconnect BCM connector. To measure voltage, connect connector terminals to positive probe and body ground to negative probe. (Scheme 4) If voltage is OK, go to next step. If voltage is not OK, replace BCM power supply circuit harness.
  3. Ground circuit inspection. Check continuity between BCM connector and body ground. (Scheme 5) If continuity is OK, circuit is normal, testing is complete. If continuity is not OK, replace BCM ground circuit harness.
Terminal No.Signal NameFuse & Fusible Link No.
7Battery(1) "F"
35Ignition "ON" Or "Start"(2) 12
36Ignition "ACC" Or "ON"(2) 6
(1) (Scheme 6) (2) (Scheme 7)

FUSE & FUSIBLE LINK INSPECTION

Scheme 4

Scheme 4
Scheme 4

Scheme 5

Scheme 5
Scheme 5

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7
Scheme 7

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