22 / 5157
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: 18 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
Check oil control valve
Clean the Rust or repair or
replace
Go to Step 2
2
Check leakage in the oil gallery
Fix the leakage
Go to Step 3
3
Check quantity of oil
Top up the oil
Go to Step 4
4
Check oil temperature
If more let the engine cool
down & oil temperature to
reduce
Go to Step 5
5
Check alignment of camshaft
Fix the alignment
Go to step 6
6
Is there any rust/oxidization observed on VVT
actuator Terminals
Clean the Rust or repair or
replace
Go to Step 7
7
Is there wiring harness electrical continuity
between ECU pin 249 & VVT IN actuator pin
1.
Go to Step 8
Establish continuity by rectifying
harness connections as per the
Circuit schematic
8
Are there any pins damaged at VVT actuator
/EMS ecu Connector
Replace the connector or
wiring harness
Go to step 9
9
Are there any pins backed out from the VVT
Actuator/EMS ecu Connector
Rectify/Replace
Connectors
Go to Step 10
10 Is VVT Actuator pin 249 short Circuited to
GND/Battery/Open
Go to Step 11
Repair the harness as per the
schematic
11 Is VVT Actuator physically Damaged
Replace VVT
Go to Step 12
12 Are there any metallic particles/Burr in VVT
actuators Tip?
Clean those burr/metallic
particles
Go to step 13
13 Are there any faults related to VVT Actuators
power supply voltages
Replace these faults by
following their rectification
procedure
Go to step 14
14 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.
1. Fuel system status
2. Engine load
3. Engine coolant temperature.
4. Long term fuel trim.
5. MAP Sensor.
6. Engine Speed.
7. Vehicle Speed.
8. Spark timing.
9. Absolute throttle position.
10. Distance Travelled after MIL ON.
11. Distance travelled since fault memory last cleared.
12. Battery voltage.
Recheck the fault, fault shall not reappear.