Last Modified: 11-29-2007 1.6 J
Service Category: Vehicle Exterior Section: Lighting (ext)
Model Year: 2008 Model: Sequoia Doc ID: RM000002ZP2005X
Title: LIGHTING (EXT): LIGHTING SYSTEM: DESCRIPTION (2008 Sequoia)

Turn Signal Light Circuit

DESCRIPTION

The turn signal flasher receives a turn signal switch signal from the headlight dimmer switch, and illuminates the front turn signal light, outer rear view mirror and rear combination light.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1.

CHECK TURN SIGNAL LIGHT

(a) Check that the turn signal lights blink.

Result

Result

Proceed to

All turn signal lights do not blink

A

Only front turn signal light does not blink

B

Only rear combination light does not blink

C

Only door mirror foot light does not blink*

D

*: w/ Side turn signal light.

A

2.

INSPECT FUSE (LH-IG, TURN-HAZ)

(a) Remove the LH-IG fuse from the main body ECU.

(b) Remove the TURN-HAZ fuse from the engine room junction block.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

LH-IG fuse

Always

Below 1 Ω

TURN-HAZ fuse

Always

Below 1 Ω

(d) Reinstall the LH-IG and TURN-HAZ fuses.

OK

3.

CHECK HARNESS AND CONNECTOR (TURN SIGNAL FLASHER - BATTERY, IGNITION SWITCH, BODY GROUND)

(a) Disconnect the H39 turn signal flasher assembly connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

H39-3 (IG) - Body ground

Ignition switch ON

11 to 14 V

Ignition switch off

Below 1 V

H39-1 (B) - Body ground

Always

11 to 14 V

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

J29-4 (E) - Body ground

Always

Below 1 Ω

(d) Reconnect the turn signal flasher assembly connector.

OK

4.

INSPECT FRONT TURN SIGNAL LIGHT BULB

(a) Temporarily replace the front turn signal light bulb with a new or normally functioning one LIGHTING (EXT): HEADLIGHT ASSEMBLY: DISASSEMBLY (2008 Sequoia)+ .

(b) Check that the front turn signal light turn on.

OK:

Front turn signal light turn on

OK

5.

CHECK HARNESS AND CONNECTOR (FRONT TURN SIGNAL LIGHT - TURN SIGNAL FLASHER, BODY GROUND)


(a) for LH:

(1) Disconnect the A15 Front turn signal light LH connector.

(2) Disconnect the H39 turn signal flasher assembly connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A15-3 (B) - H39-10 (LTRN)

Always

Below 1 Ω

A15-2 (E) - Body ground

Always

Below 1 Ω

A15-3 (B) - Body ground

Always

10 kΩ or higher

(4) Reconnect the turn signal flasher assembly connector.

(5) Reconnect the Front turn signal light LH connector.

(b) for RH:

(1) Disconnect the A16 Front turn signal light RH connector.

(2) Disconnect the H39 turn signal flasher assembly connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A16-3 (B) - H39-17 (RTRN)

Always

Below 1 Ω

A16-2 (E) - Body ground

Always

Below 1 Ω

A16-3 (B) - Body ground

Always

10 kΩ or higher

(4) Reconnect the turn signal flasher assembly connector.

(5) Reconnect the Front turn signal light RH connector.

OK

6.

INSPECT REAR TURN SIGNAL LIGHT BULB

(a) Temporarily replace the rear turn signal light bulb with a new or normally functioning one LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY: DISASSEMBLY (2008 Sequoia)+ .

(b) Check that the rear turn signal light turn on.

OK:

Rear turn signal light turn on.

OK

7.

CHECK HARNESS AND CONNECTOR (REAR COMBINATION LIGHT - TURN SIGNAL FLASHER, BODY GROUND)


(a) for LH:

(1) Disconnect the O23 rear combination light assembly LH connector.

(2) Disconnect the H39 turn signal flasher assembly connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

O23-1 (TRN) - H39-2 (LL)

Always

Below 1 Ω

O23-2 (E) - Body ground

Always

Below 1 Ω

O23-1 (TRN) - Body ground

Always

10 kΩ or higher

(4) Reconnect the turn signal flasher assembly connector.

(5) Reconnect the rear combination light assembly LH connector.

(b) for RH:

(1) Disconnect the O22 rear combination light assembly RH connector.

(2) Disconnect the H39 turn signal flasher assembly connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

O22-1 (TRN) - H39-8 (LR)

Always

Below 1 Ω

O22-2 (E) - Body ground

Always

Below 1 Ω

O22-1 (TRN) - Body ground

Always

10 kΩ or higher

(4) Reconnect the turn signal flasher assembly connector.

(5) Reconnect the rear combination light assembly RH connector.

OK

8.

INSPECT OUTER REAR VIEW MIRROR ASSEMBLY


(a) Remove the outer rear view mirror assembly LIGHTING (EXT): SIDE TURN SIGNAL LIGHT ASSEMBLY: REMOVAL (2008 Sequoia) .

(b) Apply battery voltage to the terminals and check that the side turn signal light turn on.

OK:

Tester Connection

Specified Condition

Positive battery (+) → 4 (B)

Negative battery (-) → 3 (E)

Side turn signal light turn on.

(c) Reinstall the outer rear view mirror assembly.

OK

9.

CHECK HARNESS AND CONNECTOR (OUTER REAR VIEW MIRROR - TURN SIGNAL FLASHER, BODY GROUND)


(a) for LH:

(1) Disconnect the M5 outer rear view mirror assembly LH connector.

(2) Disconnect the H39 turn signal flasher assembly connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

M5-4 (B) - H39-2 (LL)

Always

Below 1 Ω

M5-3 (E) - Body ground

Always

Below 1 Ω

M5-4 (B) - Body ground

Always

10 kΩ or higher

(4) Reconnect the turn signal flasher assembly connector.

(5) Reconnect the outer rear view mirror assembly LH connector.

(b) for RH:

(1) Disconnect the L6 outer rear view mirror assembly RH connector.

(2) Disconnect the H39 turn signal flasher assembly connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

L6-4 (B) - H39-8 (LR)

Always

Below 1 Ω

L6-3 (E) - Body ground

Always

Below 1 Ω

L6-4 (B) - Body ground

Always

10 kΩ or higher

(4) Reconnect the turn signal flasher assembly connector.

(5) Reconnect the outer rear view mirror assembly RH connector.

OK

10.

INSPECT OUTER REAR VIEW MIRROR SUB-ASSEMBLY

(a) Temporarily replace the outer rear view mirror sub assembly with a new or normally functioning one MIRROR (EXT): OUTER REAR VIEW MIRROR: REMOVAL (2008 Sequoia) .

(b) Check that the side turn signal light turn on.

OK:

Side turn signal light turn on.

OK