TIAGO TIGOR BSVI - SERVICE MANUAL - DTC 24-12-2021

TATA BSVI Gasoline Program – EMS ECU Bosch DTC Troubleshooting Service Manual Version: 1.2 Date: 18-12-2019 Prepared By: Sunita Mandlik Checked By: Yeshwant Jadhav Approved By: Satish Kumar Document Part No: 2921 02 xxx xxxx Page: 1151 of 1498 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. P0579-11: Cruise Control Multi-Function Input “A” Circuit Range/ Performance – Circuit Short to Ground Overview: ISO Code P0579 – 11 Customer Symptom 1.Vehicle will come out of Cruise control. 2. Cruise Control Function will not work. Fault Effects (On Vehicle) 1.Vehicle will come out of Cruise control. 2. Cruise Control Function will not work. Lamp Status (If Any) CE lamp ON after 3 drive cycle Fault Detection Condition This fault gets logged when the Cruise control switches pin of EMS ECU is short circuited to Ground. Normal Operating Condition Cruise Control switches function as per the design intention. Probable Trouble Area Faulty cruise control switches button, Wiring Harness Connections, EMS ECU Healing Condition After 1 Drive cycles and ignition ON Fault permanent deletion 1. Scan tool Service 14 2. Stack Over Flow. 3. 40 warm up cycles. 4. ECU flashing 5. ECU power fail Component Details: Cruise control switches are open non latchable switches. Whose electrical contacts will be closed when the switches is pressed. Cruise control (sometimes known as Speed Control or Autocruise) is a system that automatically controls th e speed o f a motor vehicle . The system is a servomechanism t hat takes over th e throttle o f the car to maintain a steady speed as set by the driver. Preliminary Checks: 1. Loose / Damaged connection between Cruise control switch and EMS ECU. 2. Check for any damage of pins at EMS ecu connector / Cruise control switches connector. 3. Check whether the EMS ecu connector / Cruise control switches connector are damaged. 4. Check the continuity from the cruise control switches connector pins to the ECU pin. Trouble Shooting:- Step Checks IF YES IF NO 1. Is there any rust/oxidation observed on switches terminals. Clean the rust or repair or replace Go to step 2 2. Check the continuity between the EMS ECU pin 123 and Cruise control switches pin1. Also check the continuity between the Cruise control switches pin 2 and Ground. Is Continuity proper? Go to step 3 Establish continuity as per the circuit schematic. 3. Check whether the EMS ECU pin 123 is short circuited to GND. Repair the harness as per the schematic Go to step 4 4. Check whether Cruise control switch pin 2 is short circuited to GND. Go to step 5 Repair the harness as per the schematic