HARRIER BOOK 2

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: 752 of 1052

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.

P245B-4B: EGR Cooler bypass control circuit range / performance – EGR high pressure cooler bypass command

(over temperature)

Overview:

DTC Description (User Friendly)

EGR high pressure cooler bypass command (over

temperature)

ECU Pin Number

A069

Customer Symptom

Increased fuel consumption, Poor Engine performance, If

vehicle operated for long with fault, Engine components might

be damaged.

Fault Effects (On Vehicle)

Increased fuel consumption.

Lamp Status (If Any)

MIL OFF CEL OFF

Fault Detection Condition (Root cause)

The hardware detects an over temperature error on the digital

output power stage for the actuator (A069).

Normal Operating Condition

No Fault

Probable Trouble Area

Check, whether there is dis-continuity in wiring harness

between EGR bypass valve and EMS ECU.

Check for ECM pin A069 is SC to Battery

AC Relay faulty,

EMS ECU faulty

Healing Condition

Rectify the error

Clear through diagnostic tool

Ignition OFF & ON

Component Details:

EGR cooler bypass valve is a solenoid valve, which controls the flow of EGR air through EGR

cooler based on EGR cooler load and Exhaust gas temperature. EMS ECU controls the valve opening from 0% to 100%

through PWM command to valve.

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. Loose/ Damaged Connections between EGR cooler by pass valve and EMS ECU.

4. Loose/ Damaged Connections between EGR cooler by pass valve and Main relay supply.

5. Check for damage of pins or back out of pins at ECU connector / EGR cooler by pass valve connector.

Trouble Shooting:

Step Checks

IF YES

IF NO

Check for any mechanical damage in EGR cooler by pass

valve

Replace faulty valve Go to next step

Is there wiring harness electrical continuity between ECU

pin A069 & valve pin

. Also Check continuity between the

Main Relay supply and the Valve pin

Go to next step

Rectify the wiring

harness

connections as per

the circuit

schematic.

Are there any pins damaged at EMS ECU Connector

Replace the

Go to Next Step