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: 1161 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. P1557-2: Cruise Control System-Vehicle Speed Too Low – General Signal Failure Overview: ISO Code P1557-2 Customer Symptom Vehicle speed decrease too low as compare to set speed and eventually come out of cruise mode. Fault Effects (On Vehicle) Vehicle will come out of Cruise mode & Vehicle speed will be too low (uphill scenario). Lamp Status (If Any) No lamp indication Fault Detection Condition This fault gets logged when vehicle speed is decreases rapidly so that cruise will be deactivated as vehicle speed can’t be controlled by throttle. Normal Operating Condition Vehicle will be in cruise mode. Probable Trouble Area Cruise Control switches 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: N.A Trouble Shooting:- No need for any trouble shooting procedure as there is no problem with vehicle or cruise control software. Actually it’s a limitation in cruise control strategy not a fault. But customer can look it as a fault that’s why such DTC is defined. The reason for this DTC detection is that vehicle speed was too low as compare to driver set speed target, such scenario mostly occur while travelling in uphill where due to gravity the vehicle speed decrease rapidly and automatically vehicle will come out of cruise mode. DTC’s confirmation:- N.A DTC’s Healing Confirmation: - After rectification, ensure the following points by referring engine parameters using TML diagnostic tool before handing over to customer. Circuit Schematic Diagram: