Q501 4 Cylinder MT Application DTC Troubleshooting Data Version: 0.1 Date: 21-Sep-2018 Prepared By: Mithi Prasad, Sarang Kulkarni, Manish Gupta Checked By: Yogesh Jadhav Approved By: Satish Kumar P Page: 873 of 1052 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. P0571-94: Brake Switch “A” Circuit – Brake pedal switch signal incorrect after event (0/1 error) Overview: DTC Description (User Friendly) Brake pedal switch signal incorrect after event (0/1 error) ECU Pin Number K035, K010 Customer Symptom CEL ON, Cruise Control will be disabled Fault Effects (On Vehicle) Cruise Control will be disabled Lamp Status (If Any) MIL OFF, CEL ON Fault Detection Condition (Root cause) EMS ECU receives 0V at pin K010 and 12 V at Pin K035 when Brake Pedal is pressed or released. Normal Operating Condition No Fault Code Probable Trouble Area WH connections between EMS ECU and Brake Pedal switch connector. Brake pedal stuck in grey Zone between two switches. Healing Condition Rectify the error Clear through diagnostic tool Ignition OFF & ON Component Details: For safety reasons, Brake pedal is equipped with two Switches. These switches transition their states when the brake pedal is pressed. EMS ecu uses the brake press information in its control strategies like Torque demand calculation, Gear Shift indication, Accelerator pedal stuck detection, vehicle start function when clutch sensor fails etc. Preliminary Checks: 1. Check whether the customer voice / view about the issue is matching with the fault effects mentioned above. If yes, go ahead with next steps. If not, check for other DTC’s presence. 2. Check whether similar complaints are earlier reported. If yes, perform the preliminary checks with respect to earlier issue closure. 3. Check for any other faults presence related to ECU Internal power supplies; Follow rectification process for those faults, before proceeding further. 4. Check whether the Brake Pedals is moving freely. Else look for Mechanical issues and correct them. 5. Check for Wiring Dis-continuity between Brake Pedal Switch & EMS ECU. If found, fix them 6. Check whether the Main Brake switch is stuck open 7. Check whether the redundant brake switch is stuck open. Trouble Shooting: Step Checks IF YES IF NO 1. Check for any other faults presence related to ECU Internal power supplies / Accelerator pedal sensor / Brake Pedal Sensor. Follow rectification process for the faults, before proceeding further Go to Step 2 2 Check for electrical continuity between ECU to Brake Pedal sensor connector as per the circuit schematic. Continuity exists? Go to next step Establish continuity by rectifying harness
RkJQdWJsaXNoZXIy MTIwNTUz