NEXON DIAGNOSTIC MANUAL

Nexon Gasoline – EMS ECU Bosch

DTC Troubleshooting Manual

Version: 0.1

Date: 26-08-2017

Prepared By: Sunu S Babu/Yogesh Jadhav

Checked By: Yeshwant Jadhav

Approved By: Satish Kumar

Document Part No: 2921 02 224 A1736

Page: 354 of 1203

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.

Trouble Shooting:-

Step Checks

IF YES

IF NO

Check the bypass valve Connector for any damage

Replace connector

Go to step 2

Is there any dirt or Rust on Connector

Remove the

connector and clean

it and refit it tightly

Go to Step 3

Perform the bypass valve actuator test. Is the test

successful

Go to step 4

Some problem in

Wiring harness

connections

Check the continuity between the EMS ECU pin 241 and

connector pin 2. Check the continuity between the bypass

valve connector pin 1 and EMS main relay supply. Is

continuity test successful

Go to step 5

Establish continuity

by rectifying wiring

harness

connections as per

the schematic.

Is the by pass connector pin 1 short Circuited to

battery/Ground. Perform this test by keeping Ignition Off.

Go to Step 6

Rectify Wiring

Harness

connections as per

the schematic

Check whether the bypass valve control pin 241 is Short

Circuited to battery

Rectify Wiring

Harness

connections as per

the schematic

Go to step 7

7. Is the resistance across the bypass valve terminals less

than

ohms?

Go to Step 8

Replace the

Injector of cylinder

Check whether any bypass pins are backed out at ECU

Connector or Injector connector

Rectify the

connections

Go to Step 9

Is there any physical damage to bypass valve connector /

ECU Connector

Replace the

respective

connectors

Go to step 10

10 If the fault still persists

Replace the EMS

ECU

Repeat the above

procedure for

reconfirmation

DTC’s confirmation:-

After rectification, ensure the following points by referring engine parameters using TML diagnostic tool before

handing over to customer.

Perform the actuator test for bypass valve. Test result should be successful.