FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0703

DTC P0703 BRAKE S/W MALFUNCTION

Component Location:





GENERAL DESCRIPTION
The HIVEC Automatic Transmission's function, of intelligence control, is based on the Fuzzy Control System. The Fuzzy Control System determines optimal gear positions as related to driver's intention and current driving conditions. The Brake Switch provides important information by deciding whether the vehicle is decelerating by the depression of the brake pedal, or if the speed is decreasing because the vehicle is running on the uphill.

DTC DESCRIPTION
The TCM(PCM) sets this code if a Brake Switch signal is input continuously, for an extended period of time, when the vehicle is supposed to be running (moving).

DTC Detecting Condition:





MONITOR SCANTOOL DATA
1. Connect Scantool to data link connector(DLC).
2. Ignition "ON" & Engine "OFF".
3. Monitor the "BRAKE LAMP SWITCH" parameter on the Scantool.
4. Depress and release Foot Brake.





5. Does "STOP LAMP SWITCH" follow the reference data?

YES
^ Fault is intermittent caused by poor contact in the sensor's and/or TCM(PCM)'s connector or was repaired and TCM(PCM) memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure

NO
^ Go to "Terminal & Connector Inspection" procedure.

TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?

YES
^ Repair as necessary and go to "Verification of Vehicle Repair procedure.

NO
^ Go to "Signal Circuit Inspection" procedure.

SIGNAL CIRCUIT INSPECTION
1. Ignition "ON" & Engine "OFF".
2. Disconnect "BRAKE LAMP SWITCH" connector.
3. Measure voltage between terminal "1" of the sensor harness connector and chassis ground.

C84:





4. Is voltage within specifications?

YES
^ Go to "Component Inspection" procedure.

NO
^ Check for Short to power circuit in harness. Repair as necessary and Go to "Verification of Vehicle Repair" procedure.

COMPONENT INSPECTION
1. Check "STOP LAMP SWITCH"
1) Ignition "OFF" & Engine "OFF".
2) Disconnect "STOP LAMP SWITCH" connector and Remove "STOP LAMP SWITCH".
3) Measure resistance between terminal "1" and "2" of the STOP LAMP SWITCH when plunger of the STOP LAMP SWITCH is pushed in.

C84:





4) Is resistance within specifications?

YES
^ Go to "Adjust STOP LAMP SWITCH" as below.

NO
^ Replace "STOP LAMP SWITCH" as necessary and Go to "Verification of Vehicle Repair" procedure.

2. Adjust "STOP LAMP SWITCH" Clearance
1) Ignition "OFF" & Engine "OFF".
2) Reinstall "STOP LAMP SWITCH".
3) Adjust "STOP LAMP SWITCH" Clearance as below.





4) After Adjusting, has problem been solved?

YES
^ Go to "Verification of Vehicle Repair" procedure.

NO
^ Substitute with a known-good TCM/PCM and check for proper operation. If the problem is corrected, replace TCM/PCM and go to "Verification of Vehicle Repair" procedure.

VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.

1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Using a Scantool, Clear DTC.
3. Operate the vehicle within DTC Enable conditions in General information.
4. Are you DTCs present?

YES
^ Go to the applicable troubleshooting procedure.

NO
^ System performing to specification at this time.