256 / 561
TIAGO/TIGOR AMT Gasoline
DTC Troubleshooting Guide
Version: 4.0
Date: 18-04-2017
Author: Sathi/Anupama
Page: 122 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.
37.
P2906 -02: Generated Engine Torque– Signal not valid
Overview:
ISO Code
P2906-02
Customer Symptom
Jerky or sluggish gearshifts
Fault Effects (On Vehicle)
Jerky or sluggish gearshifts
Lamp Status (If Any)
Transmission Fault Lamp OFF
Fault Detection Condition
This fault gets detected after Ignition On if EMS signals the
TCU that generated torque information on CAN is invalid.
Normal Operating Condition
EMS signals the TCU that generated torque information on
CAN is valid
Probable Trouble Area
Wiring Harness Connections / EMS / TCU
Healing Condition
200 milliseconds after valid sensor signal
Component Details:
Generated torque signal is transmitted via CAN bus to the TCU. In case of this particular DTC being set, it is expected that an
EMS component is at fault.
Preliminary Checks:
1) Loose/ Damaged EMS sensor/actuator Connections.
2) Check for damage or back out of pins at EMS connector and TCU connector.
3) Check correct fitment of ground cable connections on vehicle chassis.
Trouble Shooting:-
Step Checks
IF YES
IF NO
1.
Is there any rust/oxidation observed on EMS or
TCU connectors?
Clean the Rust or repair
or replace
Go to Step 2
2
Check with the EMS diagnostic tool, are there
EMS related DTC’s present?
Rectify all DTC’s related
to EMS (Refer EMS
service manual)
Go to step 3
3
Is TCU power connections on TCU connector pins
5, 1, 3? Specifically check Ignition supply toggling
with key on/off.
Go to Step 4
Check and rectify
harness power
connections.
4
Fault Still Persists?
Recheck the above steps
Follow the steps again
for reconfirmation
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.
After key and engine ON with TML TCU diagnostic tool connected, monitor the engine torque and confirm that it
changes with accelerator pedal press.
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: