Lighting (interior) (diagnostics & Circuit Testing) Lexus IS F I

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Various switches or sensors are represented as inputs for the different systems mentioned in this information. Where direct electrical connections do not exist between components, signals may be carried across the different networks (BEAN, CAN) that exist on the vehicle. If a signal needs to travel from a CAN system to a BEAN system, the gateway ECU allows the signal to travel between these different networks. Some of these different signals can be confirmed or inspected using the Techstream.

SYSTEM DESCRIPTION

The system representations shown below are intended to show concept of operation, and may not precisely reflect the construction of the system on the vehicle.

1. ILLUMINATED ENTRY SYSTEM General The illuminated entry system has the seven control functions shown in the following chart: Control Operation Outline Operation Light Actuation Area-linked Turn ON When the key enters any actuation area around the doors, the front and rear seat illumination turns on. Front Seat Illumination Rear Seat Illumination Door Mirror Foot Lights Transmitter-linked Turn ON When the following condition is satisfied, the lights turn on. Any door is unlocked using the transmitter. Front Seat Illumination Rear Seat Illumination Footwell Lights*3 Door Mirror Foot Lights Door Open-linked Turn ON When the following condition is satisfied, the lights turn on. Any door is opened. Engine Switch Illumination Front Interior Lights Rear Interior Light Door Courtesy Lights Footwell Lights*3 Door Close-linked Turn OFF*1 When the following condition is satisfied, the lights turn off. All doors are closed. Front Seat Illumination Rear Seat Illumination Engine Switch Illumination Front Interior Lights Rear Interior Light Door Courtesy Lights Footwell Lights*3 Door Mirror Foot Lights Door Lock-linked Turn OFF*2 When the following condition is satisfied, the lights turn off. All doors are locked. Power Source-linked Turn ON When the following condition is satisfied, the shift illumination turns on. Power source is changed from OFF to ACC or IG-ON. Shift Illumination Turn OFF*2 When the following condition is satisfied, the lights turn off. Power source is changed from OFF to ACC or IG-ON. Front Seat Illumination Rear Seat Illumination Engine Switch Illumination Door Courtesy Lights Footwell Lights*3 Door Mirror Foot Lights Battery Saving Turn OFF When the following two conditions have been satisfied, these lights turn off. A key is not in the actuation area. There are no changes in the condition of the doors for 20 minutes. Front Seat Illumination Rear Seat Illumination Engine Switch Illumination Front Interior Lights Rear Interior Light Door Courtesy Lights Footwell Lights*3 *1: Illuminates for approximately 15 seconds, then fades out over three seconds. *2: Stops the illumination immediately and starts to fade out over three seconds. *3: Go off when the light control rheostat is adjusted to the minimum level.

HOW TO PROCEED WITH TROUBLESHOOTING

HINT

1. Use the following procedure to troubleshoot the lighting system.
2. *: Use the Techstream.

1. VEHICLE BROUGHT TO WORKSHOP NEXT: Go to next step
2. CUSTOMER PROBLEM ANALYSIS AND SYMPTOM CHECK NEXT: Go to next step
3. INSPECT BATTERY VOLTAGE Standard Voltage 11 to 14 V If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step. NEXT: Go to next step
4. INSPECT MULTIPLEX COMMUNICATION SYSTEM (BEAN)* Use the Techstream to check if the Multiplex Communication System (MPX) is functioning normally. Result Result Proceed to MPX DTC is not output A MPX DTC is output B B --> Go to step 7 A: Go to next step
5. PROBLEM SYMPTOMS TABLE Result Result Proceed to If fault is not listed in problem symptoms table A If fault is listed in problem symptoms table B B --> Go to step 7 A: Go to next step
6. OVERALL ANALYSIS AND TROUBLESHOOTING* Data List / Active Test. Refer to «DATA LIST / ACTIVE TEST»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-diagnostics-circuit-testing__data-list-active-test) Terminals of ECU. Refer to «TERMINALS OF ECU»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-diagnostics-circuit-testing) Inspection NEXT: Go to next step
7. ADJUST, REPAIR OR REPLACE NEXT: Go to next step
8. CONFIRMATION TEST NEXT --> END

OPERATION CHECK

1. INSPECT SEAT LIGHT CONTROL OPERATION NOTE: Perform this inspection with the customize parameter at the initial setting. HINT: The seat light control illuminates the lights below. Front seat light Rear seat light The operation and condition of this control are described below. Operation Condition Fade in Any door is opened. Illuminate for approximately 15 seconds, and then fade out When any of the following conditions is met, the front seat light and rear seat light illuminate for approximately 15 seconds, and then fade out The key enters any actuation area around the doors when the engine switch is off and all doors are closed. Any door is unlocked when the engine switch is off and all doors are closed. The engine switch is turned from on (ACC) to off when all doors are closed. All doors are closed when any door is opened and the engine switch is off. Fade out immediately When either of the following conditions is met, the front seat light and rear seat light fade out. The engine switch is turned from off to on (ACC or IG) when all doors are closed. All doors are locked when the engine switch is off.
2. INSPECT INTERIOR LIGHT CONTROL OPERATION NOTE: Perform this inspection with the customize parameter at the initial setting. HINT: The interior light control illuminates the lights below. Front interior light Rear interior light The operation and condition of this control are described below. Operation Condition Fade in Any door is opened. Fade out All doors are closed.
3. INSPECT FOOTWELL LIGHT CONTROL OPERATION NOTE: Perform this inspection with the customize parameter at the initial setting. HINT: The footwell light control illuminates the lights below. Footwell light LH Footwell light RH The operation and condition of this control are described below. Operation Condition Fade in When any of the following conditions is met, the footwell light LH and footwell light RH fade in. Any door is opened. The engine switch is turned from off to on (IG) when the shift lever in P. Dim The shift lever is adjusted to any position other than P when the engine switch is on (IG) and the shift lever is in P. Illuminate for approximately 15 seconds, and then fade out When any of the following conditions is met, the footwell light LH and foot light RH illuminate for approximately 15 seconds and then fade out. Any door is unlocked when the engine switch is off and all doors are closed. The engine switch is turned from on (IG) to off when all doors are closed. All doors are closed when any door is opened and the engine switch is off. Fade out immediately All doors are locked when the engine switch is off and all doors are closed.
4. INSPECT SHIFT LIGHT CONTROL OPERATION NOTE: Perform this inspection with the customize parameter at the initial setting. HINT: The shift light control illuminates the lights below. Shift light The operation and condition of this control are described below. Operation Condition Fade in When any of the following conditions is met, the shift light comes on. The engine switch is on (ACC) The engine switch is on (IG) Fade out The engine switch is off
5. INSPECT BATTERY SAVER Seat light With the engine switch off, a key is not in the actuation area, and no vehicle condition changes, check that the lights illuminated by the seat light control remain illuminated for approximately 20 minutes, and then turn off. HINT: When the light control operation conditions are met, the battery saver control is canceled. Interior light With the engine switch off, a key is not in the actuation area, and no vehicle condition changes, check that the lights illuminated by the interior light control remain illuminated for approximately 20 minutes, and then turn off. HINT: When the light control operation conditions are met, the battery saver control is canceled. Footwell light With the engine switch off, a key is not in the actuation area, and no vehicle condition changes, check that the lights illuminated by the footwell light control remain illuminated for approximately 20 minutes, and then turn off. HINT: When the light control operation conditions are met, the battery saver control is canceled.

CUSTOMIZE PARAMETERS

HINT

The following items can be customized.

Note. When a customer requests a change in a function, first make sure that the function can be customized. Be sure to make a note of the current settings before customizing. When troubleshooting a function first make sure that the function is set to the default setting.

ILLUMINATED ENTRY

PROBLEM SYMPTOMS TABLE

HINT

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

INTERIOR LIGHT SYSTEM

Scheme 7

Scheme 8

Scheme 9

1. CHECK MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH) Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition RD-7 (GND2) - Body ground W-B - Body ground Ground Always Below 1 V RA-11 (LCTY) - Body ground BR - Body ground Illumination signal (From rear door courtesy switch LH) Rear LH door is closed 11 to 14 V RA-11 (LCTY) - Body ground BR - Body ground Illumination signal (From rear door courtesy switch LH) Rear LH door is open Below 1 V RA-20 (MPX1) - Body ground GR - Body ground Multiplex communication signal circuit Engine switch on (IG) Signal waveform RK-5 (BECU) - Body ground G-R - Body ground Multiplex communication power source circuit Always 11 to 14 V P1-14 (DCTY) - Body ground W - Body ground Illumination signal (From driver side courtesy switch) Driver's side door is closed 11 to 14 V P1-14 (DCTY) - Body ground W - Body ground Illumination signal (From driver side courtesy switch) Driver's side door is open Below 1 V P1-16 (RCTY) - Body ground BE - Body ground Illumination signal (From rear door courtesy switch RH) Rear RH door is closed 11 to 14 V P1-16 (RCTY) - Body ground BE - Body ground Illumination signal (From rear door courtesy switch RH) Rear RH door is open Below 1 V J75-15 (FSPT) - Body ground R - Body ground Illumination signal (To footwell lights) Footwell lights come on Below 1 V J75-15 (FSPT) - Body ground R - Body ground Illumination signal (To footwell lights) Footwell lights go off 11 to 14 V J75-21 (MPX2) - Body ground GR - Body ground Multiplex communication signal circuit Engine switch on (IG) Signal waveform RA-15 (ALTB) - Body ground SB - Body ground Power source circuit Always 11 to 14 V J75-4 (UL2) - Body ground P - Body ground Interior light switch (ON/OFF) signal Interior light switch on Below 1 V J75-4 (UL2) - Body ground P - Body ground Interior light switch (ON/OFF) signal Interior light switch off 11 to 14 V J75-24 (PCYL) - Body ground Y - Body ground Illumination signal (From front door courtesy light LH) Passenger's side door is open Below 1 V J75-24 (PCYL) - Body ground Y - Body ground Illumination signal (From front door courtesy light LH) Passenger's side door is closed 11 to 14 V P1-13 (DCYL) - Body ground G - Body ground Illumination signal (From front door courtesy light RH) Driver's side door is open Below 1 V P1-13 (DCYL) - Body ground G - Body ground Illumination signal (From front door courtesy light RH) Driver's side door is closed 11 to 14 V J75-25 (LGCY) - Body ground L - Body ground Illumination signal (From luggage door courtesy switch) Luggage door is open Below 1 V J75-25 (LGCY) - Body ground L - Body ground Illumination signal (From luggage door courtesy switch) Luggage door is closed 11 to 14 V J75-23 (PCTY) - Body ground B - Body ground Illumination signal (From front door courtesy switch LH) Passenger's side door is open Below 1 V J75-23 (PCTY) - Body ground B - Body ground Illumination signal (From front door courtesy switch LH) Passenger's side door is closed 11 to 14 V
2. CHECK MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH) Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition LD-3 (GND) - Body ground W-B - Body ground Ground Always Below 1 V LD-8 (SGND) - Body ground W-B - Body ground Ground Always Below 1 V LD-9 (SGND) - Body ground W-B - Body ground Ground Always Below 1 V LD-18 (MPXB) - Body ground LG - Body ground Multiplex communication power source circuit Always 11 to 14 V Q1-2 (ILE) - Body ground V - Body ground Illumination signal (To front interior light) Interior light switch in DOOR position and interior lights come on Below 1 V Q1-2 (ILE) - Body ground V - Body ground Illumination signal (To front interior light) Interior light switch in DOOR position and interior lights go off 11 to 14 V Q1-3 (RCTY) - Body ground R - Body ground Illumination signal (To shift illumination) Shift illumination comes on Below 1 V Q1-3 (RCTY) - Body ground R - Body ground Illumination signal (To shift illumination) Shift illumination goes off 11 to 14 V Q1-4 (LCTY) - Body ground LG - Body ground Illumination signal (To door mirror foot light) Door mirror foot lights come on 11 to 14 V Q3-15 (MPX1) - Body ground GR - Body ground Multiplex communication signal circuit Engine switch on (IG) Signal waveform A30-17 (MPX2) - Body ground GR - Body ground Multiplex communication signal circuit Engine switch on (IG) Signal waveform Q3-3 (LGCY) - Body ground W - Body ground Illumination signal (to seat illumination) Seat illumination comes on Below 1 V Q3-3 (LGCY) - Body ground W - Body ground Illumination signal (to seat illumination) Seat illumination goes off 11 to 14 V Q3-11 (BDCY) - Body ground P - Body ground Interior light switch (Door) signal Interior light switch on Below 1 V Q3-11 (BDCY) - Body ground P - Body ground Interior light switch (Door) signal Interior light switch off 11 to 14 V
3. CHECK OVERHEAD JUNCTION BLOCK Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition R5-1 (+B1) - Body ground L - Body ground Power source circuit Always 11 to 14 V R5-3 (RRMP) - Body ground BE - Body ground Rear personal light power source circuit Always 11 to 14 V R5-4 (ILLB) - Body ground L - Body ground Rear interior light power source circuit Always 11 to 14 V R5-12 (CTY) - Body ground W - Body ground Seat illumination light circuit Seat illumination goes off 11 to 14 V R5-12 (CTY) - Body ground W - Body ground Seat illumination light circuit Seat illumination comes on Below 1 V R5-13 (ILL) - Body ground BR - Body ground Interior light circuit Interior lights go off 11 to 14 V R5-13 (ILL) - Body ground BR - Body ground Interior light circuit Interior lights come on Below 1 V R5-14 (SHFT) - Body ground Y - Body ground Shift illumination circuit Shift illumination goes off 11 to 14 V R5-14 (SHFT) - Body ground Y - Body ground Shift illumination circuit Shift illumination comes on Below 1 V R5-18 (GND3) - Body ground W-B - Body ground Ground Always Below 1 V R5-19 (RGND) - R5-18 (GND3) W-B - W-B Interior light ground Always Below 1 V R5-32 (LILL) - R5-12 (CTY) B - W Seat illumination circuit Always Below 1 ohms R5-33 (RILL) - R5-13 (ILL) P - BR Interior light circuit Always Below 1 ohms R5-34 (CILL) - R5-18 (GND3) P - W-B Interior light switch (ON/OFF) circuit Interior light switch off 11 to 14 V R5-34 (CILL) - R5-18 (GND3) P - W-B Interior light switch (ON/OFF) circuit Interior light switch on Below 1 V R5-35 (DOOR) - R5-18 (GND3) G - W-B Interior light switch (DOOR) circuit Interior light switch off 11 to 14 V R5-35 (DOOR) - R5-18 (GND3) G - W-B Interior light switch (DOOR) circuit Interior light switch on Below 1 V R5-36 (MPX) - Body ground GR - Body ground Multiplex communication signal circuit Engine switch on (IG) Signal waveform

DIAGNOSIS SYSTEM

1. DESCRIPTION Lighting system data can be read from the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the Techstream to check for malfunctions and perform repairs.
2. CHECK DLC3 Check the DLC3. Refer to «GENERAL INFORMATION»(/lexus/is-f/i-2007-2014/remont/hoistjack/#introduction) .
3. INSPECT BATTERY VOLTAGE Standard Voltage 11 to 14 V If the voltage is below 11 V, recharge or replace the battery before proceeding.

DATA LIST / ACTIVE TEST

1. READ DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time. NOTE: In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / (desired system) / Data List. Read the Data List according to the display on the Techstream. BODY (MAIN BODY ECU RH) Tester Display Measurement Item/Range Normal Condition Diagnostic Note ACC SW Engine switch / ON (ACC) or OFF ON: Engine switch on (ACC or IG) OFF: Engine switch off - IG SW Engine switch / ON (IG) or OFF ON: Engine switch on (IG) OFF: Engine switch off - Luggage Courtesy SW Luggage door courtesy switch / ON or OFF ON: Luggage door is open OFF: Luggage door is closed D Door Courtesy SW Driver side courtesy switch / ON or OFF ON: Driver side door is open OFF: Driver side door is closed - P Door Courtesy SW Passenger side courtesy switch / ON or OFF ON: Passenger side door is open OFF: Passenger side door is closed - Rear Door Courtesy SW Rear (LH or RH) courtesy switch / ON or OFF ON: Rear door (LH or RH) is open OFF: Rear door (LH and RH) is closed - Illumination SW Front interior light switch (marked ON / OFF) signal / ON or OFF ON: Front interior light switch (marked ON / OFF) is pushed in OFF: Front interior light switch (marked ON / OFF) is not pushed in - BODY NO. 3 (MAIN BODY ECU LH) Tester Display Measurement Item/Range Normal Condition Diagnostic Note Interior Light Front interior light switch (marked DOOR) signal / ON or OFF ON: Front interior light switch (marked DOOR) is pushed in OFF: Front interior light switch (marked DOOR) is not pushed in - Shift Light Control Shift illumination control / AVAIL or NOT AVL Customized value is displayed - IG SW Engine switch / ON or OFF ON: Engine switch on (IG) OFF: Engine switch off
2. PERFORM ACTIVE TEST HINT: Using the Techstream to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / (desired system) / Active Test. Perform the Active Test according to the display on the Techstream. BODY (MAIN BODY ECU RH) Tester Display Test Part Control Range Diagnostic Note Step Light Operation Footwell lights ON/OFF - BODY NO. 3 (MAIN BODY ECU LH) Tester Display Test Part Control Range Diagnostic Note Shift Light Operation Shift light ON/OFF - Interior Light Operation Interior lights ON/OFF - Interior Light (Dim) Operation Seat lights ON/OFF

DESCRIPTION

The main body ECU RH detects the condition of each door courtesy switch and sends a signal to each ECU via the multiplex communication circuit.

Scheme 10

INSPECTION PROCEDURE

HINT

The procedure is the same for each door courtesy switch circuit. First, inspect the suspected door courtesy switch circuit.

Scheme 11

Scheme 12

Scheme 13

Scheme 14

1. READ VALUE USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Body / Data List. Read the display on the Techstream. BODY (MAIN BODY ECU RH) Tester Display Measurement Item/Range Normal Condition Diagnostic Note D door Courtesy SW Driver side door courtesy switch signal / ON or OFF ON: Driver side door is open OFF: Driver side door is closed - P door Courtesy SW Passenger side door courtesy switch signal / ON or OFF ON: Passenger side door is open OFF: Passenger side door is closed - Rear door Courtesy SW Rear (LH and RH) door courtesy switch / ON or OFF ON: Rear door (LH or RH) is open OFF: Rear door (LH and RH) is closed - OK Condition sign can be displayed. Result Result Proceed to OK A Driver side door courtesy switch does not operate B Front passenger side door courtesy switch does not operate C Both rear door courtesy switches do not operate D D --> See step 7 C --> See step 5 B --> See step 3 A --> See step 2
2. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-diagnostics-circuit-testing__problem-symptoms-table)
3. INSPECT FRONT DOOR COURTESY SWITCH LH Inspect the front door courtesy switch LH. Refer to «INSPECTION»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information) . OK Door courtesy switch is normal. NG --> See step 9 OK: Go to next step
4. CHECK HARNESS AND CONNECTOR (FRONT DOOR COURTESY SWITCH LH - MAIN BODY ECU RH) Disconnect the P1 ECU connector. Disconnect the Q11 switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition P1-14 (DCTY) - Q11-1 Always Below 1 ohms P1-14 (DCTY) or Q11-1 - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH)
5. INSPECT FRONT DOOR COURTESY SWITCH RH Inspect the front door courtesy switch RH. Refer to «INSPECTION»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information) . OK Door courtesy switch is normal. NG --> See step 10 OK: Go to next step
6. CHECK HARNESS AND CONNECTOR (FRONT DOOR COURTESY SWITCH RH - MAIN BODY ECU RH) Disconnect the J75 ECU connector. Disconnect the P9 switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition J75-23 (PCTY) - P9-1 Always Below 1 ohms J75-23 (PCTY) or P9-1 - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH)
7. INSPECT DOOR COURTESY SWITCH (REAR LH AND REAR RH) Inspect the rear door courtesy switches LH and RH. Refer to «INSPECTION»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information) . OK Door courtesy switches are normal. NG --> See step 11 OK: Go to next step
8. CHECK HARNESS AND CONNECTOR (DOOR COURTESY SWITCH (REAR LH OR REAR RH) - MAIN BODY ECU RH) Check the wire harness between the cowl side junction block RH and rear door courtesy switch LH. Disconnect the RA junction block connector. Disconnect the Q17 switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition RA-11 (LCTY) - Q17-1 Always Below 1 ohms RA-11 (LCTY) or Q17-1 - Body ground Always 10 kohms or higher Check the wire harness between the main body ECU RH and rear door courtesy switch RH. Disconnect the P1 ECU connector. Disconnect the P16 switch connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition P1-16 (RCTY) - P16-1 Always Below 1 ohms P1-16 (RCTY) or P16-1 - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH)
9. REPLACE FRONT DOOR COURTESY SWITCH LH. Refer to «COMPONENTS»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information)
10. REPLACE FRONT DOOR COURTESY SWITCH RH. Refer to «COMPONENTS»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information)
11. REPLACE DOOR COURTESY SWITCH (REAR LH OR REAR RH). Refer to «COMPONENTS»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information)

The seat illumination can be canceled using the overhead junction block switch.

The seat illumination is controlled by the main body ECU LH based on various signals received through BEAN communication.

The main body ECU LH includes a MOS-FET (Metal Oxide Semiconductor - Field Effect Transistor) circuit that fades the seat illumination in and out by duty control.

This MOS-FET circuit has an overheat protection function as a fail-safe. If the main body ECU LH becomes excessively hot, the seat illumination turns off and remains off.

Normal operation will resume when the conditions required to turn on the seat illumination are met again.

Scheme 15

Scheme 16

Scheme 17

Scheme 18

Scheme 19

Scheme 20

1. CHECK PERSONAL LIGHT (OPERATION) HINT: The personal lights and seat illumination share the same power source circuit. Therefore, if none of them come on, inspect the power source circuit first. Push the personal light switches. Check that the personal lights come on. OK Personal lights come on. NG --> See step 7 OK: Go to next step
2. PERFORM ACTIVE TEST USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Body No. 3 / Active Test. Check the operation. BODY NO. 3 (MAIN BODY ECU LH) Tester Display Test Part Control Range Diagnostic Note Interior Light (Dim) Operation Front and rear seat illumination ON/OFF - OK Front and rear seat illumination comes on. Result Result Proceed to Front seat illumination does not come on A Rear seat illumination does not come on B Neither front nor rear seat illumination comes on C OK D HINT: If the rear seat illumination comes on normally, but the front seat illumination does not come on, there is an open circuit in the overhead junction block. C --> See step 5 B --> See step 3 A --> See step 8 D --> See step 9
3. INSPECT SPOT LIGHT ASSEMBLY (REAR SEAT ILLUMINATION) Remove the spot light assembly. Connect a positive (+) lead from the battery to terminal 2 and a negative (-) lead to terminal 5, and then check that the seat illumination comes on. OK Seat illumination comes on. NG --> See step 10 OK: Go to next step
4. CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - SPOT LIGHT ASSEMBLY) Disconnect the R8 spot light assembly connector. Disconnect the R5 overhead junction block connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition R8-2 (ILLB) - R5-4 (ILLB) Always Below 1 ohms R8-5 (LILL)- R5-32 (LILL) Always Below 1 ohms R8-2 (ILLB) - Body ground Always 10 kohms or higher R8-5 (LILL) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 8
5. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD JUNCTION BLOCK) Disconnect the Q3 main body ECU LH connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition Q3-3 (LGCY) - Body ground Always 11 to 14 V NG --> See step 6 OK --> REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH)
6. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD JUNCTION BLOCK) Disconnect the Q3 main body ECU LH connector. Disconnect the R5 overhead junction block connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition Q3-3 (LGCY) - R5-12 (CTY) Always Below 1 ohms Q3-3 (LGCY) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 8
7. CHECK HARNESS AND CONNECTOR (POWER SOURCE) Disconnect the R5 overhead junction block connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition R5-1 (+B1) - Body ground Always 11 to 14 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 8
8. REPLACE OVERHEAD JUNCTION BLOCK. Refer to «INSPECTION»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information)
9. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-diagnostics-circuit-testing__problem-symptoms-table)
10. REPLACE SPOT LIGHT ASSEMBLY. Refer to «COMPONENTS»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information)

The shift illumination is controlled by the main body ECU LH based on various signals received through BEAN communication.

The main body ECU LH includes a MOS-FET (Metal Oxide Semiconductor - Field Effect Transistor) circuit that fades the shift illumination in and out by duty control.

This MOS-FET circuit has an overheat protection function as a fail-safe. If the main body ECU LH becomes excessively hot, the shift illumination turns off and remains off.

Normal operation will resume when the conditions required to turn on the shift illumination are met again.

Scheme 21

Scheme 22

Scheme 23

1. CHECK PERSONAL LIGHT (OPERATION) HINT: The personal lights and shift illumination share the same power source circuit. Therefore, if none of them come on, inspect the power source circuit first. Push the switches for the personal lights. Check that the personal lights come on. OK Personal lights come on. NG --> See step 5 OK: Go to next step
2. PERFORM ACTIVE TEST USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Body No. 3 / Active Test. Check the operation. BODY NO. 3 (MAIN BODY ECU LH) Tester Display Test Part Control Range Diagnostic Note Shift Light Operation Shift illumination ON/OFF - OK The shift illumination comes on. NG --> See step 3 OK --> See step 7
3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD JUNCTION BLOCK) Disconnect the Q1 main body ECU LH connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition Q1-3 (RCTY) - Body ground Always 11 to 14 V NG --> See step 4 OK --> REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH)
4. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD JUNCTION BLOCK) Disconnect the Q1 main body ECU LH connector. Disconnect the R5 overhead junction block connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition Q1-3 (RCTY) - R5-14 (SHFT) Always Below 1 ohms Q1-3 (RCTY) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 6
5. CHECK HARNESS AND CONNECTOR (POWER SOURCE) Disconnect the R5 overhead junction block connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition R5-1 (+B1) - Body ground Always 11 to 14 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 6
6. REPLACE OVERHEAD JUNCTION BLOCK. Refer to «COMPONENTS»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information)
7. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-diagnostics-circuit-testing__problem-symptoms-table)

The interior lights turn on when a door is opened, and turn off when the door is closed. This illumination setting can be canceled using the overhead junction block switch.

In addition, the interior lights blink while the theft deterrent system is sounding an alarm.

The interior lights is controlled by the main body ECU LH based on various signals received through BEAN communication.

The main body ECU LH includes a MOS-FET (Metal Oxide Semiconductor - Field Effect Transistor) circuit that fades the interior lights in and out by duty control.

This MOS-FET circuit has an overheat protection function as a fail-safe. If the main body ECU LH becomes excessively hot, the interior lights turn off and remain off.

Normal operation will resume when the conditions required to turn on the interior lights are met again.

If the vehicle is equipped with scuff plate lights, their operation timing is the same as that of the interior lights.

Scheme 24

Scheme 25

Scheme 26

Scheme 27

Scheme 28

1. CHECK SEAT ILLUMINATION (OPERATION) HINT: The personal lights and interior lights share the same power source. Therefore, if none of them come on, inspect the power source circuit first. Push the switches for the personal lights. Check that the personal lights come on. OK Personal lights come on. NG --> See step 7 OK: Go to next step
2. PERFORM ACTIVE TEST USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Body No. 3 / Active Test. Check the operation. BODY NO. 3 (MAIN BODY ECU LH) Tester Display Test Part Control Range Diagnostic Note Interior Light Operation Interior lights ON/OFF - OK The front and rear interior lights come on. Result Result Proceed to Front interior light does not come on A Rear interior light does not come on B Neither front nor rear interior light comes on C OK D C --> See step 5 B --> See step 3 A --> REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH) D --> See step 8
3. INSPECT SPOT LIGHT ASSEMBLY (REAR INTERIOR LIGHT) Remove the spot light assembly. Connect a positive (+) lead from the battery to terminal 2 and a negative (-) lead to terminal 4, and then check that the interior light comes on. OK The interior light comes on. NG --> See step 9 OK: Go to next step
4. CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - SPOT LIGHT ASSEMBLY) Disconnect the R8 rear dome light assembly connector. Disconnect the R5 overhead junction block connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition R8-2 (ILLB) - R5-4 (ILLB) Always Below 1 ohms R8-4 (RILL) - R5-33 (RILL) Always Below 1 ohms R8-2 (ILLB) - Body ground Always 10 kohms or higher R8-4 (RILL) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH)
5. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD JUNCTION BLOCK) Disconnect the Q1 main body ECU LH connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition Q1-2 (ILE) - Body ground Always 11 to 14 V NG --> See step 6 OK --> REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH)
6. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD JUNCTION BLOCK) Disconnect the Q1 main body ECU LH connector. Disconnect the R5 overhead junction block connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition Q1-2 (ILE) - R5-13 (ILL) Always Below 1 ohms Q1-2 (ILE) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH)
7. CHECK HARNESS AND CONNECTOR (POWER SOURCE) Disconnect the R5 overhead junction block connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition R5-1 (+B1) - Body ground Always 11 to 14 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH)
8. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-diagnostics-circuit-testing__problem-symptoms-table)
9. REPLACE SPOT LIGHT ASSEMBLY. Refer to «COMPONENTS»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information)

The main body ECU RH receives information on the front interior light switch (marked ON/OFF).

The main body ECU LH receives information on the front interior light switch (marked DOOR).

According to the position of each switch, the main body ECU RH controls the interior lights, and the main body ECU LH controls the illuminated entry system.

Scheme 29

Scheme 30

Scheme 31

Scheme 32

Scheme 33

Scheme 34

1. READ VALUE USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / (desired system) / Data List. Read the display on the Techstream. BODY (MAIN BODY ECU RH) Tester Display Measurement Item/Range Normal Condition Diagnostic Note Illumination SW Front interior light switch (marked ON/OFF) signal / ON or OFF ON: Front interior light switch (marked ON/OFF) is pushed in OFF: Front interior light switch (marked ON/OFF) is not pushed in - BODY NO. 3 (MAIN BODY ECU LH) Tester Display Measurement Item/Range Normal Condition Diagnostic Note Interior Light Front interior light switch (marked DOOR) signal / ON or OFF ON: Front interior light switch (marked ON/OFF) is pushed in OFF: Front interior light switch (marked ON/OFF) is not pushed in - OK Switch condition can be displayed. Result Result Proceed to Indication for "Illumination SW" does not change A Indication for "Interior Light" does not change B Indications for both "Illumination SW" and "Interior Light" do not change C OK D C --> See step 6 B --> See step 4 A --> See step 2 D --> See step 7
2. INSPECT OVERHEAD JUNCTION BLOCK Remove the overhead junction block. Measure the resistance according to the value(s) in the table. Standard Resistance Tester Connection Condition Specified Condition R5-34 (CILL) - R5-18 (GND3) Front interior light switch (marked ON/OFF) is not pushed in 10 kohms or higher R5-34 (CILL) - R5-18 (GND3) Front interior light switch (marked ON/OFF) is pushed in Approx. 10 ohms NG --> See step 8 OK: Go to next step
3. CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - MAIN BODY ECU RH) Disconnect the R5 overhead junction block connector. Disconnect the J75 main body ECU RH connector. Measure the resistance according to the value(s) in the table. Standard Resistance Tester Connection Condition Specified Condition R5-34 (CILL) - J75-4 (UL2) Always Below 1 ohms R5-34 (CILL) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH)
4. INSPECT OVERHEAD JUNCTION BLOCK Remove the overhead junction block. Measure the resistance according to the value(s) in the table. Standard Resistance Tester Connection Condition Specified Condition R5-35 (DOOR) - R5-18 (GND3) Front interior light switch (marked DOOR) is not pushed in 10 kohms or higher R5-35 (DOOR) - R5-18 (GND3) Front interior light switch (marked DOOR) is pushed in Approx. 10 ohms NG --> See step 8 OK: Go to next step
5. CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - MAIN BODY ECU LH) Disconnect the R5 overhead junction block connector. Disconnect the Q3 main body ECU LH connector. Measure the resistance according to the value(s) in the table. Standard Resistance Tester Connection Condition Specified Condition R5-35 (DOOR) - Q3-11 (BDCY) Always Below 1 ohms R5-35 (DOOR) - Body ground Always 10 kohms or higher NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH)
6. INSPECT OVERHEAD JUNCTION BLOCK Remove the overhead junction block. Measure the resistance according to the value(s) in the table. Standard Resistance Tester Connection Switch Condition Specified Condition R5-35 (DOOR) - R5-18 (GND3) Front interior light switch (marked DOOR) is not pushed in 10 kohms or higher R5-35 (DOOR) - R5-18 (GND3) Front interior light switch (marked DOOR) is pushed in Approx. 10 ohms R5-34 (CILL) - R5-18 (GND3) Front interior light switch (marked ON/OFF) is not pushed in 10 kohms or higher R5-34 (CILL) - R5-18 (GND3) Front interior light switch (marked ON/OFF) is pushed in Approx. 10 ohms NG --> See step 8 OK --> REPAIR OR REPLACE HARNESS OR CONNECTOR (OVERHEAD JUNCTION BLOCK GROUND CIRCUIT)
7. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-diagnostics-circuit-testing__problem-symptoms-table)
8. REPLACE OVERHEAD JUNCTION BLOCK. Refer to «COMPONENTS»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-service-information)

The main body ECU RH receives information regarding the door lock position switches, door courtesy switches, and engine switch, and turns on each footwell light.

This illumination setting can be canceled using the light control rheostat.

Scheme 35

Scheme 36

1. PERFORM ACTIVE TEST USING TECHSTREAM Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Body / Active Test. Check the operation. BODY (MAIN BODY ECU RH) Tester Display Test Part Control Range Diagnostic Note Step Light Operation Footwell lights ON/OFF - OK Footwell lights come on. HINT: The footwell lights RH and LH share the same power source. If either of the lights does not come on, there may be a problem in the part of the circuit that relates to that light. Therefore, inspect that part of the circuit. NG --> See step 2 OK --> See step 3
2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU RH - BATTERY) Disconnect the J75 main body ECU RH connector. Measure the voltage according to the value(s) in the table. Standard Voltage Tester Connection Condition Specified Condition J75-15 (FSPT) - Body ground Always 11 to 14 V NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> REPLACE MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH)
3. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(/lexus/is-f/i-2007-2014/remont/interiorillumination-lights/#lighting-interior-diagnostics-circuit-testing__problem-symptoms-table)

See also:
• INSPECTION
• GENERAL INFORMATION
• DATA LIST / ACTIVE TEST
• TERMINALS OF ECU
• PROBLEM SYMPTOMS TABLE