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: 884 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.
Preliminary Checks:
1) Loose/ Damaged Connections between Sensor and EMS ECU.
2) Check for back out of pins at both Sensor connector and ECU connector.
3) Check for damage of pins at both Sensor connector and ECU connector.
4) Check the continuity from Sensor connector pins to the ECU pins.
Trouble Shooting:
Step Checks
IF YES
IF NO
1.
Is there any rust/oxidization observed on VVT actuator
Terminals
Clean the Rust or
repair or replace
Go to Step 2
2. Is there wiring harness electrical continuity between ECU
pin 240 & VVT IN actuator pin 1.
Go to Step 3
Establish continuity
by rectifying
harness
connections as per
the Circuit
schematic
3. Are there any pins damaged at VVT actuator /EMS ecu
Connector
Replace the
connector or wiring
harness
Go to step 4
4
Are there any pins backed out from the VVT Actuator/EMS
ecu Connector
Rectify/Replace
Connectors
Go to Step 5
5
Is VVT Actuator pin 240 short Circuited to GND/Battery
Go to Step 6
Repair the harness
as per the
schematic
6
Is VVT Actuator physically Damaged
Replace VVT
Go to Step 7
7.
Are there any metallic particles/Burr in VVT actuators Tip?
Clean those
burr/metallic
particles
Go to step 8
8
Are there any faults related to VVT Actuators power supply
voltages
Replace these faults
by following their
rectification
procedure
Go to step 9
9
Fault Still Persists?
Replace VVT
Actuator 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, fault shall not reappear.




