Taillight Circuit

LIGHTING: LIGHTING SYSTEM: Taillight Circuit

Taillight Circuit

DESCRIPTION

Front light:
The front light ECU receives taillight switch information from the combination switch, and turns on the clearance light.
Rear light:
The rear multiplex network ECU receives taillight switch information from the combination switch, and turns on the taillights and license plate light.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. CHECK OPERATION OF FRONT LIGHT OR REAR LIGHT
(a) When the taillight switch is operated, check that the following lights illuminate.

Result

B -- PERFORM ACTIVE TEST USING TECHSTREAM (TAILLIGHT AND LICENSE LIGHT)
A -- Continue to next step.
2. PERFORM ACTIVE TEST USING TECHSTREAM (CLEARANCE LIGHT)
(a) Select the ACTIVE TEST, use the Techstream to generate a control command, and then check that the clearance light illuminates.

Body No. 5 (Front light ECU)

OK:
Light illuminates.
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
NG -- Continue to next step.
3. INSPECT FUSE (FR TAIL, FR CTRL-AM)
(a) Remove the FR CTRL-AM and FR CTRL-AM fuses from the engine room No. 1 relay block.
(b) Measure the resistance of the fuses.
Standard resistance:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
4. REPLACE CLEARANCE LIGHT BULB
(a) Temporarily replace the clearance light bulb with a new or normally functioning one.
(b) Check that the bulb illuminates.
OK:
Clearance light bulb illuminates.
OK -- END
NG -- Continue to next step.
5. CHECK WIRE HARNESS (ECU - BATTERY)

(a) Disconnect the 1Y ECU connector.
(b) Measure the voltage of the wire harness side connector.
Standard voltage:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
6. CHECK WIRE HARNESS (ECU - HEADLIGHT AND BODY GROUND)

(a) Check the wire harness between the headlight (clearance LH) and front light ECU, and the headlight (clearance LH) and body ground.
(1) Disconnect the 1Z ECU connector.
(2) Disconnect the B11 headlight connector.
(3) Measure the resistance of the wire harness side connectors.
Standard resistance:

(b) Check the wire harness between the headlight (clearance RH) and front light ECU, and the headlight (clearance RH) and body ground.
(1) Disconnect the 1Z junction block connector.
(2) Disconnect the B2 headlight connector.
(3) Measure the resistance of the wire harness side connectors.
Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
7. PERFORM ACTIVE TEST USING TECHSTREAM (TAILLIGHT AND LICENSE LIGHT)
(a) Select the ACTIVE TEST, use the Techstream to generate a control command, and then check that the taillight and license light illuminates.

Body No. 4 (Rear multiplex network ECU)

OK:
Light illuminates.

Result

E -- CHECK WIRE HARNESS (REAR MULTIPLEX NETWORK ECU - LICENSE PLATE LIGHT AND BODY GROUND)
D -- CHECK WIRE HARNESS (REAR MULTIPLEX NETWORK ECU - COMBINATION LIGHT AND BODY GROUND)
C -- CHECK WIRE HARNESS (REAR MULTIPLEX NETWORK ECU - REAR COMBINATION LIGHT AND BODY GROUND)
B -- INSPECT FUSE (RR TAIL)
A -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
8. INSPECT FUSE (RR TAIL)
(a) Remove the RR TAIL fuse from the rear multiplex network ECU.
(b) Measure the resistance of the fuse.
Standard resistance:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
9. CHECK WIRE HARNESS (REAR MULTIPLEX NETWORK ECU - BATTERY AND BODY GROUND)

(a) Disconnect the LB and LF ECU connectors.
(b) Measure the voltage of the wire harness side connectors.
Standard voltage:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
10. CHECK WIRE HARNESS (REAR MULTIPLEX NETWORK ECU - REAR COMBINATION LIGHT AND BODY GROUND)

(a) Check the wire harness between the rear combination light (tail inner LH) and rear multiplex network ECU, and the rear combination light (tail inner LH) and body ground.
(1) Disconnect the LA ECU connector.
(2) Disconnect the Y2 combination light connector.
(3) Measure the resistance of the wire harness side connectors.
Standard resistance:

(4) Connect the LA ECU connector.
(5) Measure the resistance of the wire harness side connector.
Standard resistance:

(b) Check the wire harness between the rear combination light (tail inner RH) and rear multiplex network ECU, and the rear combination light (tail inner RH) and body ground.
(1) Disconnect the LA ECU connector.
(2) Disconnect the Y9 combination light connector.
(3) Measure the resistance of the wire harness side connectors.
Standard resistance:

(4) Connect the LA ECU connector.
(5) Measure the resistance of the wire harness side connector.
Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
11. REPLACE REAR COMBINATION LIGHT (TAIL INNER LH OR TAIL INNER RH)
(a) Temporarily replace the rear combination light (tail inner LH or tail inner RH) with a new or normally functioning one.
(b) Check that the rear combination light illuminates.
OK:
Light illuminates.
OK -- END
NG -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
12. CHECK WIRE HARNESS (REAR MULTIPLEX NETWORK ECU - COMBINATION LIGHT AND BODY GROUND)

(a) Check the wire harness between the rear combination light (tail outer LH) and rear multiplex network ECU, and the rear combination light (tail outer LH) and body ground.
(1) Disconnect the LG ECU connector.
(2) Disconnect the X1 combination light connector.
(3) Measure the resistance of the wire harness side connectors.
Standard resistance:

(4) Connect the LG ECU connector.
(5) Measure the resistance of the wire harness side connector.
Standard resistance:

(b) Check the wire harness between the rear combination light (tail outer RH) and rear multiplex network ECU, and the rear combination light (tail outer RH) and body ground.
(1) Disconnect the LG ECU connector.
(2) Disconnect the X3 combination light connector.
(3) Measure the resistance of the wire harness side connectors.
Standard resistance:

(4) Connect the LG ECU connector.
(5) Measure the resistance of the wire harness side connector.
Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
13. REPLACE REAR COMBINATION LIGHT (TAIL OUTER LH OR TAIL OUTER RH)
(a) Temporarily replace the rear combination light (tail outer LH or tail outer RH) with a new or normally functioning one.
(b) Check that the rear combination light illuminates.
OK:
Light illuminates.
OK -- END
NG -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
14. CHECK WIRE HARNESS (REAR MULTIPLEX NETWORK ECU - LICENSE PLATE LIGHT AND BODY GROUND)

(a) Disconnect the LA ECU connector.
(b) Disconnect the Y4 license light connector.
(c) Measure the resistance of the wire harness side connectors.
Standard resistance:

(d) Connect the LA ECU connector.
(e) Measure the resistance of the wire harness side connector.
Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
15. REPLACE LICENSE PLATE LIGHT
(a) Temporarily replace the license plate light with a new or normally functioning one.
(b) Check that the light illuminates.
OK:
Light illuminates.
OK -- END
NG -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE