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Q501 4 Cylinder MT Application
DTC Troubleshooting Data
Version: 0.1
Date: 21-Sep-2018
Prepared By: Mithi Prasad, Sarang Kulkarni, Manish Gupta
Checked By: Yogesh Jadhav
Approved By: Satish Kumar P
Page: 845 of 1052
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.
P0409-78: EGR Sensor “A” Circuit – EGR high pressure valve position sensor (functional test, alignment or
adjustment incorrect)
Overview:
DTC Description (User Friendly)
EGR high pressure valve position sensor (functional test,
alignment or adjustment incorrect)
ECU Pin Number
A067, A088, A040, A079, A078
Customer Symptom
MIL ON, CEL OFF. Increased fuel consumption
Fault Effects (On Vehicle)
Slight rough Idle.
Lamp Status (If Any)
MIL ON, CEL OFF
Fault Detection Condition (Root cause)
Long term drift value is above than 8.39 or below -16.69
Normal Operating Condition
No fault
Probable Trouble Area
EGR Valve
Healing Condition
Rectify the error
Clear through diagnostic tool
Ignition OFF & ON
Component Details:
An incomplete burnt gas in exhaust is return to the cylinder. EGR works by recalculating a portion of an engine's
exhaust gas back to the engine cylinder. Intermixing the incoming air with recalculated exhaust gas dilutes the mix with
inert gas and in turn reduce the combustion temperatures for reducing NOx emissions.
Preliminary Checks:
1. Check whether the customer voice / view about the issue is matching with the fault effects mentioned in above
Table. If yes, go ahead with next steps. If not, check for other DTC’s presence.
2. Check whether other customers report similar complaints earlier. If yes, perform the preliminary checks with
respect to earlier issue closure.
3. Check for mechanical damage of EGR valve
Trouble Shooting:
Step Checks
IF YES
IF NO
1
Run the EGR High Pressure DC Motor Test Routine. Is the
Routine Result – OK?
Go to Next Step
Rectify the wiring
Harness
connections
between EGR
Valve and EMS
ECU. Repeat the
Routine Test again.
If the Routine result
is negative, then
call hotline for
confirmation to
replace EGR valve.