TIGOR AMT

TIAGO/TIGOR AMT Gasoline DTC Troubleshooting Guide Version: 4.0 Date: 18-04-2017 Author: Sathi/Anupama Page: 29 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. 8. P0904-02: Shift Position Sensor Circuit– Fixed Signal High Level Overview: ISO Code P0904-02 Customer Symptom Transmission Fault Lamp ON, Creeping inactive, Transmission going automatically to neutral while driving. No gearshift Fault Effects (On Vehicle) Creeping inactive, Transmission going automatically to neutral while driving. No gearshift No EOL self-tuning. Lamp Status (If Any) Transmission Fault Lamp ON Fault Detection Condition This fault gets detected after Ignition On when the Engine is not cranking and Sensor & battery Supply voltage is in proper range and a high value (no edges) of the signal is detected for a timeout. Normal Operating Condition Shift Position signal will be in a valid range corresponding to the total travel of the shift actuator between 1/2 and 5/R ranks. Signal has valid period and duty cycle. Probable Trouble Area Loose mechanical fitment of TCU/ Sensor loose/damage/short (internal)/ TCU internal damage Healing Condition 1000 milliseconds after valid sensor signal Component Details: The Shift Position sensor is PWM type sensor which outputs a signal duty cycle in proportion to the Shift actuator position. Preliminary Checks: 1) If this DTC occurs in combination with DTC P1853, refer remedy for P1853. 2) Loose/ Damaged mechanical fitments of TCU (TCU to kit mounting). 3) Check for any visible damage to TCU. 4) Check correct fitment of ground cable connections on vehicle chassis. Trouble Shooting:- On first occurrence, clear the DTC and drive the vehicle for 2-3 kms, read the DTC again. On fault confirmed again, follow below steps. Step Checks IF YES IF NO 1. Unmount and remove the TCU from the valve body. Inspect the condition of the Shift position sensor (refer fig below). Is the sensor visibly undamaged? Go to Step 2 Replace the sensor/TCU. 2. Inspect the sensor connection to TCU main board for loose fit/disconnection/pin damage. Is the sensor connected properly? Go to Step 3 Fit the sensor back properly. If sensor connector damage then replace the TCU. 3. Replace the 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.