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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: 187 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
ECUpins 215,205 &Coolant Temperature Sensor connector
pins 1,2.
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 Signal Pin 215 Short Circuited to GND/Battery
Repair the harness
as per the schematic Go to Step 6
6
Is Sensor physically Damaged
Replace Sensor
Go to Step 7
7
Check the resistance between the pins 215 & 205.
Compare this resistance value with the Sensor
Temperature – Resistance characteristics and check
whether the Temperature corresponding to the Resistance
value found is matching the Engine Parameter displayed on
tool – Coolant Temperature.
Go to Step 8
Replace Sensor
8
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.
Method A:
Soak the vehicle for more than 12 hrs (preferably over night)
Then check if all the system temperature values (coolant, fuel, inlet air) are close to each other.
Method B:
Check the resistance between the pins 215 & 205. Compare this resistance value with the Sensor Temperature –
Resistance characteristics and check whether the Temperature corresponding to the Resistance value found is
matching the Engine Parameter displayed on tool – Coolant Temperature.