TIAGO

TIAGO AMT Gasoline

DTC Troubleshooting Guide

Version: 2.0

Date: 06-06-2016

Author: Sathi/Anupama

Page: 104 of 424

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.

31.

P2900 -01: Sport Switch input circuit Switch Stuck

Overview:

ISO Code

P2900-01

Customer Symptom

Vehicle not shifting in sport mode or economy mode

Fault Effects (On Vehicle)

Vehicle not shifting in sport mode or economy mode

Lamp Status (If Any)

Transmission Fault Lamp OFF

Fault Detection Condition

This fault gets detected after Ignition On if TCU detects that

timeout.

Normal Operating Condition

It is expected that the Sport switch input will not always be in

Probable Trouble Area

Wiring Harness Connections / Gear Lever/TCU

Healing Condition

1000 milliseconds after valid sensor signal

Component Details:

Sport switch is a digital input from the Gear lever to the TCU. If the input is active, TCU changes the gear shift points to

introduce more sportiness in the drive.

Preliminary Checks:

1) Loose/ Damaged Gear Lever Connections.

2) Check for damage or back out of pins at TCU connector.

3) Check correct fitment of ground cable connections on vehicle chassis.

Trouble Shooting:-

Step Checks

IF YES

IF NO

Is there any Pin backout/rust/oxidation

observed on TCU connectors?

Clean the Rust or repair or

replace

Go to Step 2

Check for correct mechanical operation of

the sport switch, ensure it properly returns

to its original position after being pressed

and released. Is it getting stuck sometimes?

Repair/Replace the Gear

lever

Go to Step 3

Check for continuity from TCU pin 7(28 pin

vehicle connector) to Gear lever pin 5, is

continuity OK?

Go to step 4

Ensure correct connection

as per schematic

Check for proper ground connection on

Gear lever Pin 4, is ground OK?

Go to step 5

Check and rectify

Check for any short circuit to ground/battery

with switch unpressed on Gear lever Pin 5,

is there any short?

Check and rectify/Replace

the lever if internal short

Go to step 6

Check for any short circuit to ground/battery

with switch unpressed on TCU Pin 7, is

there any short?

Check and rectify the

harness

Go to step 7

Is TCU power proper on TCU connector

pins 5, 1 and 3? Specifically check Ignition

supply toggling with key on/off.

Go to Step 8

Check and rectify harness

power connections.

With the lever connected and TCU

connector disconnected, check continuity of

TCU pin 77 with ground toggling with switch

press/release. Is continuity observed when

switch is pressed and not continuous when

released?

Replace the TCU

Replace the gear lever