TIGOR AMT

TIAGO/TIGOR AMT Gasoline DTC Troubleshooting Guide Version: 4.0 Date: 18-04-2017 Author: Sathi/Anupama Page: 191 of 427 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. 60. P1889-04: Shift electrovalve – Open Circuit Overview: ISO Code P1889-04 Customer Symptom Transmission Fault Lamp ON, No gearshifts, Vehicle not cranking, sudden shift to neutral while driving Fault Effects (On Vehicle) No gearshifts, Vehicle not cranking, sudden shift to neutral while driving, no EOL selftuning Lamp Status (If Any) Transmission Fault Lamp ON Fault Detection Condition This fault gets detected after Ignition On when shift electrovalve is commanded OFF and an open circuit is detected on the valve. Normal Operating Condition TCU does not detect open circuit Probable Trouble Area TCU mountings/ valve body damage / Electro valve / TCU Healing Condition 50 milliseconds after valid detection of healed condition Component Details: The Shift electro valve is a proportional flow control solenoid valve which drives linear motion of the hydraulic shift selection actuator. This component is mounted on the valve body and makes internal electrical contact with the TCU. Preliminary Checks: 1) Loose/ Damaged Connections between Electro valve and TCU. 2) Loose/ Damaged mechanical fitments of TCU (TCU to valve body mounting). 3) Check correct fitment of ground cable connections on vehicle chassis. Trouble Shooting:- Step Checks IF YES IF NO 1 Unmount and remove the TCU from the valve body. Inspect the condition of the Shift Electrovalve (EV3) (refer fig below). Is the Valve or valve pins visibly undamaged? Go to Step 2 Replace the electrovalve/Valve Body. 2 Inspect the Shift Electrovalve connector on TCU main board (refer fig below) for loose fit/disconnection/pin damage. Is the Electrovalve connected properly? Go to Step 3 Fit the TCU to valve body back ensuring proper contacts. If TCU side connector damage then replace the TCU. 3 If Problem persists, Replace the valve body and then if still persists, replace TCU DTC’s confirmation:- After rectification, clear all DTC’s and ensure the following points by referring TCU parameters using TML diagnostic tool before handing over to customer.  Drive the vehicle through all gears in both Automatic and Manual modes  Ensure no DTC is active and Transmission Fault Lamp is OFF. Circuit Schematic Diagram: