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TIAGO/TIGOR AMT Gasoline
DTC Troubleshooting Guide
Version: 4.0
Date: 18-04-2017
Author: Sathi/Anupama
Page: 353 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.
121.
P1844 -07: Grid Self tuning Procedure – Error
Overview:
ISO Code
P1844-07
Customer Symptom
Transmission Fault Lamp ON,
No gearshifts ,
Vehicle not picking up
Fault Effects (On Vehicle)
No gearshifts ,
Vehicle not picking up
Lamp Status (If Any)
Transmission Fault Lamp ON
Fault Detection Condition
This fault gets detected after Ignition On if TCU detects that
the Grid self tuning service procedure has not been done or
not successfully completed
Normal Operating Condition
Grid self tuning Procedure is successfully completed at End of
line or after service part replacements (refers service manual)
that require such procedure.
Probable Trouble Area
Wrong execution conditions/Wiring Harness Connections /
TCU
Healing Condition
Immediately after detection of valid Self tuning procedure
completion.
Component Details:
Grid Self tuning procedure is Run through a diagnostic or End of line tool, it is required by the TCU to learn the position of
each gear in the gearbox in terms of its gear and shift position sensor inputs. During this procedure, the TCU also learns the
clutch closed position and clutch stroke.
Preliminary Checks:
1) Before proceeding with rectification, ensure no other DTC in TCU except from a set of – P1844,P080A, and P185B. If
there are any other DTC’s they must be rectified first.
2) Before re-initiating the procedure check the following conditions:
a> Ignition key is ON
b> Transmission in neutral
c> Healthy battery
d> Engine speed is 0
e> Vehicle speed is 0
f> Check correct hydraulic pressure with diagnostic tool (38-51 bar)
g> Brake is not pressed
3) Check for damage or back out of pins at TCU connector.
4) Visibly check for any damage to electro valves/oil leakage/other kit components.
5) Check for loose fitting TCU/EMS and clutch position sensor connectors
6) Check correct fitment of ground cable connections on vehicle chassis.
Trouble Shooting:-
Step Checks
IF YES
IF NO
1.
Connect the TCU diagnostic tool and check for active DTC’s, are
there any active DTC’s other than the current one?
Rectify the other
DTC’s first. After
clearing DTC’s, run
the procedure
again.
Recheck from step
1
Go to Step 2
2
Initiate the Grid selftuning procedure with the diagnostic tool, wait
for ~ 2 minutes and ask for routine result.
Check for the below responses and steps to follow:
-
-