Stop Light Switch Circuit

CRUISE CONTROL: CRUISE CONTROL SYSTEM: Stop Light Switch Circuit; 2013 MY FR-S [03/2012 -]
- Stop Light Switch Circuit

DESCRIPTION

When the brake pedal is released, terminal STP of the ECM receives positive (+) battery voltage through the ECU IG2 fuse. While depressing the brake pedal, the stop light switch sends a signal to terminals STP and ST1- of the ECM. The ECM cancels cruise control drive when terminal STP receives the signal.

WIRING DIAGRAM





INSPECTION PROCEDURE

HINT
Stop light switch assembly conditions can be checked using the Techstream.

(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Cruise Control / Data List / Stop Light Switch 1 and Stop Light Switch 2.

Cruise Control





PROCEDURE

1. CHECK ECM (TERMINAL VOLTAGE)

(a) Turn the ignition switch to ON.









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

Standard voltage:





NG -- CHECK TERMINAL VOLTAGE (POWER SOURCE OF STOP LIGHT SWITCH ASSEMBLY)
OK -- Continue to next step.

2. CHECK ECM (TERMINAL VOLTAGE)

(a) Turn the ignition switch to ON.









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

Standard voltage:





NG -- CHECK TERMINAL VOLTAGE (POWER SOURCE OF STOP LIGHT SWITCH ASSEMBLY)

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures

3. CHECK TERMINAL VOLTAGE (POWER SOURCE OF STOP LIGHT SWITCH ASSEMBLY)

(a) Disconnect the stop light switch assembly connector.









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

Standard voltage:





NG -- INSPECT ECM POWER SOURCE CIRCUIT ECM Power Source Circuit
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (ECM - STOP LIGHT SWITCH ASSEMBLY)

(a) Disconnect the ECM connector.

(b) Disconnect the stop light switch assembly connector.

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

Standard resistance (Check for open):





Standard resistance (Check for short):





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

5. INSPECT STOP LIGHT SWITCH ASSEMBLY

(a) Inspect the stop light switch assembly Testing and Inspection.

NG -- REPLACE STOP LIGHT SWITCH ASSEMBLY Removal

OK -- REPLACE ECM Removal

6. CHECK TERMINAL VOLTAGE (POWER SOURCE OF STOP LIGHT SWITCH ASSEMBLY)

(a) Disconnect the stop light switch assembly connector.









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

Standard voltage:





NG -- CHECK HARNESS AND CONNECTOR (NOISE FILTER - STOP LIGHT SWITCH ASSEMBLY)
OK -- Continue to next step.

7. CHECK HARNESS AND CONNECTOR (ECM - STOP LIGHT SWITCH ASSEMBLY)

(a) Disconnect the ECM connector.

(b) Disconnect the stop light switch assembly connector.

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

Standard resistance (Check for open):





Standard resistance (Check for short):





NG -- CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - NOISE FILTER)
OK -- Continue to next step.

8. INSPECT STOP LIGHT SWITCH ASSEMBLY

(a) Inspect the stop light switch assembly Testing and Inspection.

NG -- REPLACE STOP LIGHT SWITCH ASSEMBLY Removal

OK -- REPLACE ECM Removal

9. CHECK HARNESS AND CONNECTOR (NOISE FILTER - STOP LIGHT SWITCH ASSEMBLY)

(a) Disconnect the stop light switch assembly connector.

(b) Disconnect the noise filter connector.

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

Standard resistance (Check for open):





Standard resistance (Check for short):





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

10. INSPECT NOISE FILTER

(a) Inspect the noise filter Testing and Inspection.

NG -- REPLACE NOISE FILTER Removal

OK -- REPAIR OR REPLACE HARNESS AND CONNECTOR (NOISE FILTER - BATTERY)

11. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - NOISE FILTER)

(a) Disconnect the stop light switch assembly connector.

(b) Disconnect the noise filter connector.

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

Standard resistance (Check for open):





Standard resistance (Check for short):





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

12. INSPECT NOISE FILTER

(a) Inspect the noise filter Testing and Inspection.

NG -- REPLACE NOISE FILTER Removal
OK -- Continue to next step.

13. CHECK HARNESS AND CONNECTOR (ECM - NOISE FILTER)

(a) Disconnect the ECM connector.

(b) Disconnect the noise filter connector.

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

Standard resistance (Check for open):





Standard resistance (Check for short):





NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR

OK -- REPLACE ECM Removal