C1246
BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1246; Master Cylinder Pressure Sensor Malfunction; 2013 MY FR-S [03/2012 -]
C1246 - Master Cylinder Pressure Sensor Malfunction
DESCRIPTION
The master cylinder pressure sensor is connected to the skid control ECU in the brake actuator assembly.
WIRING DIAGRAM
Refer to DTCs C1249 C1249.
INSPECTION PROCEDURE
NOTICE:
* When replacing the skid control ECU (brake actuator assembly), perform VSC sensor neutral memorization Programming and Relearning.
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
1. CHECK STOP LIGHT OPERATION
(a) Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.
OK:
NG -- INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) Exterior Lighting System
OK -- Continue to next step.
2. READ VALUE USING TECHSTREAM (MASTER CYLINDER PRESSURE SENSOR)
(a) Connect the Techstream to the DLC3.
(b) Start the engine.
(c) Select the Data List using the Techstream Data List / Active Test.
ABS/VSC/TRAC
(d) Check that the brake fluid pressure value of the master cylinder pressure sensor observed on the Techstream changes when the brake pedal is depressed.
OK:
When the pedal is depressed, the voltage displayed on the Techstream increases.
NG -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
OK -- Continue to next step.
3. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH)
(a) Select the Data List using the Techstream Data List / Active Test.
ABS/VSC/TRAC
(b) Check that the stop light switch display observed on the Techstream change according to brake pedal operation.
OK:
The Techstream displays on or off according to brake pedal operation.
NG -- CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)
OK -- Continue to next step.
4. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the ignition switch off.
(c) Start the engine.
(d) Drive the vehicle and depress the brake pedal several times to test the stop light circuit.
(e) Check if the same DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
A -- CHECK FOR INTERMITTENT PROBLEMS
5. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)
(a) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(b) Disconnect the noise filter connector.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK -- Continue to next step.
6. INSPECT NOISE FILTER
(a) Remove the noise filter Removal.
(b) Inspect the noise filter Testing and Inspection.
NG -- REPLACE NOISE FILTER Removal
OK -- Continue to next step.
7. CHECK HARNESS AND CONNECTOR (NOISE FILTER - STOP LIGHT SWITCH ASSEMBLY)
(a) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(b) Disconnect the stop light switch assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
8. INSPECT STOP LIGHT SWITCH ASSEMBLY
(a) Remove the stop light switch assembly Removal.
(b) Inspect the stop light switch assembly Testing and Inspection.
NG -- REPLACE STOP LIGHT SWITCH ASSEMBLY Removal
OK -- Continue to next step.
9. CHECK HARNESS AND CONNECTOR (STP TERMINAL)
(a) Turn the ignition switch off.
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(c) Disconnect the skid control ECU (brake actuator assembly) connector.
(d) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
HINT
*: The standard voltage value varies depending on the +BS terminal voltage value. The standard voltage is 85% of the +BS terminal voltage.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT)
OK -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal