Stop Light Switch Circuit

LIGHTING: LIGHTING SYSTEM: Stop Light Switch Circuit
- Stop Light Switch Circuit

DESCRIPTION

When the stop light switch is turned on, current flows to the stop lights to illuminate them.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. INSPECT FUSE (STOP)

(a) Remove the STOP fuse from the instrument panel junction block.

(b) Measure the resistance of the fuse.

Standard resistance:

Below 1 Ohms

NG -- REPLACE FUSE
OK -- Continue to next step.

2. INSPECT STOP LIGHT SWITCH

(a) Remove the stop light switch.

(b) Measure the resistance of the switch.

Standard resistance:

NG -- REPLACE STOP LIGHT SWITCH
OK -- Continue to next step.

3. CHECK WIRE HARNESS (STOP LIGHT SWITCH - BATTERY)

(a) Disconnect the A3 stop light switch connector.

(b) Measure the voltage of the wire harness side connector.

Standard voltage:

NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

4. CHECK STOP LIGHT CONTROL RELAY

(a) Measure the voltage of the stop light control relay.

Standard voltage:

NG -- CHECK WIRE HARNESS (STOP LIGHT CONTROL RELAY - BATTERY AND BODY GROUND)
OK -- Continue to next step.

5. INSPECT STOP LIGHT (REAR COMBINATION LIGHT)

(a) Remove the rear combination light.

(b) Connect the positive (+) lead from the battery to terminal 4 and the negative (-) lead to terminal 1, then check that the light comes on.

OK:

Light comes on.

NG -- REPLACE REAR COMBINATION LIGHT
OK -- Continue to next step.

6. INSPECT REAR STOP LIGHT (HIGH MOUNT STOP LIGHT)

(a) Remove the high mount stop light assembly.

(b) Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1, then check that the light comes on.

OK:

Light comes on

NG -- REPLACE HIGH MOUNT STOP LIGHT ASSEMBLY
OK -- Continue to next step.

7. INSPECT BRK RELAY

(a) Remove the BRK relay from the engine room No. 1 relay block.

(b) Measure the resistance of the relay.

Standard resistance:

NG -- REPLACE BRK RELAY
OK -- Continue to next step.

8. CHECK WIRE HARNESS (STOP LIGHT CONTROL RELAY - REAR STOP LIGHT)

(a) Disconnect the A43 stop light control relay connector.

(b) Disconnect the K12 and K14 rear combination light connectors.

(c) Disconnect the Q1 high mount stop light connector.

(d) Measure the resistance of the wire harness side connectors.

Standard resistance:

NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR

OK -- REPAIR OR REPLACE HARNESS AND CONNECTOR (REAR STOP LIGHT - BODY GROUND)

9. CHECK WIRE HARNESS (STOP LIGHT CONTROL RELAY - BATTERY AND BODY GROUND)

(a) Disconnect the A43 stop light control relay connector.

(b) Measure the voltage of the wire harness side connectors.

Standard voltage:

NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

10. CHECK WIRE HARNESS (STOP LIGHT SWITCH - STOP LIGHT CONTROL RELAY)

(a) Disconnect the A3 stop light switch connector.

(b) Disconnect the A43 stop light control relay connector.

(c) Measure the resistance of the wire harness side connectors.

Standard resistance:

NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR

OK -- REPLACE STOP LIGHT CONTROL RELAY