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Nexon Gasoline – EMS ECU Bosch
DTC Troubleshooting Manual
Version: 0.1
Date: 26-08-2017
Prepared By: Sunu S Babu/Yogesh Jadhav
Checked By: Yeshwant Jadhav
Approved By: Satish Kumar
Document Part No: 2921 02 224 A1736
Page: 647 of 1203
Copyright ©
TATA MOTORS Ltd.
This document must not be used in any way, such as copying and redistributing to third parties, without the consent of author.
P0504-2F: Brake switch “A/B” Correlation – Signal Erratic
Overview:
ISO Code
P0504-2F
Customer Symptom
1) Break light switch will not switch on, when breaks pressed,
2) BOA function will not work.
Fault Effects (On Vehicle)
Brake Light Lamp / Stop lamp function might get effected Break light switch
will not switch on, when breaks pressed
Lamp Status (If Any)
CE Lamp ON after 3 drive cycle
Fault Detection Condition
This fault gets logged only when Brake pedal is pressed and EMS finds no
correlation between the brake main and Redundant switches input after
calibrated threshold.
Normal Operating Condition
EMS ECU finds plausibility between Brake Switches input
Probable Trouble Area
Wiring harness Connections between Brake Switches and EMS ECU,
Improper Brake Switch Setting
Healing Condition
After 1 Drive cycle
Fault permanent deletion
1. Clear DTC Command form Scan tool
2. Stack Over Flow.
3. 40 warm up cycles.
4. ECU Flashing.
5. ECU Power-Fail
Component Details:
For safety reasons, Brake pedal is equipped with two Switches. These switches transition their states when the brake
pedal is pressed.
Preliminary Checks:
1) Loose/ Damaged Connections between Brake Switch pins and EMS ECU.
2) Check for back out of pins at ECU connector.
3) Check for damage of pins at ECU connector.
4) Check for damage of Brake switch connector.