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TIAGO/TIGOR AMT Gasoline
DTC Troubleshooting Guide
Version: 4.0
Date: 18-04-2017
Author: Sathi/Anupama
Page: 116 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.
35.
P0505 -02: Idle Engine Speed Input– Signal Implausible / Signal Wrong
Overview:
ISO Code
P0505-02
Customer Symptom
Malfunction in manual upshift/downshift,
earlier/late up shifts/downshifts,
Jerky / sluggish gear shifting.
Fault Effects (On Vehicle)
Malfunction in manual up shift/downshift, earlier/late up
shifts/downshifts, jerky/ sluggish gear shifting.
Lamp Status (If Any)
Transmission Fault Lamp OFF
Fault Detection Condition
This fault gets detected after Ignition On if EMS signals the
TCU that Engine idle speed information on CAN is invalid OR
the idle Engine speed is outside allowable limits.
Normal Operating Condition
EMS signals the TCU that Engine idle speed information on
CAN is valid.
Engine Idle speed lies in a valid band.
Probable Trouble Area
Wiring Harness Connections / EMS / TCU
Healing Condition
100 milliseconds after valid sensor signal
Component Details:
Idle engine Speed 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: