611 / 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: 607 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.
P0420-92: Catalyst System Efficiency below Threshold – Performance or Incorrect Operation
Overview:
ISO Code
P0420-92
Customer Symptom
1. Deactivation of Lambda regulation behind Catalyst.
2. Emission will
deteriorate.NoLimphome- switch ON the MIL
Fault Effects (On Vehicle)
1. Deactivation of Lambda regulation behind Catalyst.
2. Emission will deteriorate.
Lamp Status (If Any)
MIL ON after 3 drive cycles
Fault Detection Condition
This fault gets logged if the Catalyst efficiency is below a calibrated threshold.
Normal Operating Condition
Catalyst works Efficiently
Probable Trouble Area
Catalytic converter, LAMBDA Sensor and its wiring Harness connections
Healing Condition
Engine Running and after 3 Drive Cycles
Fault permanent deletion
1. Clear DTC Command form Scan tool
2. Stack Over Flow.
3. 40 warm up cycles.
4.ECU flashing
5. ECU Power-Fail
Component Details:
Catalyst in the catalytic converter.
Preliminary Checks:
1. Check the catalyst
2. Check for any LAMBDA Sensor related fault codes
Trouble Shooting:-
Step Checks
IF YES
IF NO
1
Is Catalyst OK?
Go to step 2
Replace Catalyst
2.
Any Faults related to LAMBDA Sensor?
Rectify them by
following their
rectification
procedure
Go to step 3
3
Fault Still Persists?
Replace Catalytic
converter and if fault
still persists then
replace EMS ecu.
Repeat the
procedure for
reconfirmation.