NEXON EV
X114H: DTC Troubleshooting Document for BMS
Version: 3.0
Date: 01
th
July 2020
Copyright © TATA MOTORS Ltd.
This document must not be used in anyway, such as copying and redistributing to third parties, without the consent of author.
P122A - 1A:- BMS insulation fault second level alarm - circuit resistance below threshold
Overview:
ISO Code
P122A - 1A
Customer Symptom
HV system shut off
Fault Effects (On Vehicle)
NA
Lamp Status (If Any)
HV Fault alarm on cluster
Fault occurrence scenario(In the order of
probability)
Water Ingress
Normal Operating Condition
NA
Probable Trouble Area
Insulation damage in HV system
Healing Condition
System Details:
Battery insulation is moniterd by the BMS through the insulation monitoring device. Pack insulation can
fail due water ingress.
Preliminary Checks:
Inspection Method:
Connect the tool and communicate to the battery pack as instructed through APPENDIX-C
Read DTC information of DTC ID –
P122A – 1A
Rectification Action:
4)
If DTC is appearing in real time, clear DTC information through service tool
5)
If DTC is not appearing in real-time but has only occurred before, store the snapshot data.
6)
Clear the DTC information on the respective DTC ID.
DTC’s confirmation:
After clearing, ensure the following points by referring to BMS DTC list.
5)
Read DTC ID –
P122A – 1A
for the existence of DTC information.
6)
If DTC still exists, reflash the battery pack using the service tool with the latest release SW available
in PLM database.
7)
Read DTC ID –
P122A – 1A
for the existence of DTC information post flashing.
8)
If DTC still exists, the HV battery pack component has to be replaced as instructed by the respective
ECU replacement guide
Component Location & Image;Connector Location; Connector View & Information: -
APPENDIX-A




