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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: 253 of 1203
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.
Trouble Shooting:-
Step Checks
IF YES
IF NO
1.
Is there any rust/oxidization observed on Sensor Terminals Clean the Rust or
repair or replace
Go to Step 2
2.
Is there wiring harness electrical continuity between
ECUpins246, 204, 230 &Lambda Sensor connector pins 2,
3, 4. Also Check continuity between the Main Relay supply
and the Lambda Sensor Connector pin 1.
Go to Step 3
Establish continuity
by rectifying
harness
connections as per
the Circuit
schematic
3. Are there any pins damaged at Sensor/EMS ECU
Connector
Replace the
connector or wiring
harness
Go to step 4
4
Are there any pins backed out from the Sensor/EMS ECU
Connector
Rectify/Replace
Connectors
Go to Step 5
5
Is Sensor getting GND at pin 204.
Repair the harness
as per the schematic Go to Step 6
6
Is Sensor Signal Pin 230 or heater pin 246, Short Circuited
to Battery/Ground.
Repair the harness
as per the schematic Go to Step 7
7
Is Sensor physically Damaged
Replace Sensor
Go to Step 8
8
Is Sensor poisoned or contaminated
Replace Sensor
Go to Step 9
9. Is there any leakage in Exhaust system
Repair the
damage/leaks
Go to step 10
10 Fault Still Persists?
Replace Sensor and
then Fault still
persists then
Replace EMS ECU
Follow the steps
again for
reconfirmation
DTC’s confirmation:-
After rectification, ensure the following points by referring engine parameters using TML diagnostic tool before
handing over to customer.
Recheck the fault using TML Diagnostic tool, Fault shall not appear.