NEXON DIAGNOSTIC MANUAL

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: 747 of 1203

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.

P0626-15: Alternator -Generator Field/F Terminal Circuit High– Circuit Short to Battery or Open

Overview:

ISO Code

P0626-15

Customer Symptom

Vehicle start and battery charging while driving may get

affected.No

Limphome-

switch ON the service lamp

Fault Effects (On Vehicle)

Vehicle start and battery Charging while driving may get affected

Lamp Status (If Any)

CE lamp ON after 3 drive cycle

Fault Detection Condition

This fault gets logged if the DF Signal pin of EMS ECU is Short circuited to

Battery or Open Circuited.

Normal Operating Condition

Plausible DF signal from Alternator / Healthy Wiring harness Connections

between EMS ECU and Alternator Terminal -

Probable Trouble Area

Alternator Faulty, Wiring Harness Connections

Healing Condition

At Engine Running and after 1 drive cycle of Fault rectification

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:

Alternator DF signal gives the Current Electrical loadon vehicle – information to EMS ECU. Based on which, EMS

ECU calculates, how much additional torque to be developed for Alternator to deliver the load.

Preliminary Checks:

1) Loose/ Damaged Connections between Alternator Terminal –

and EMS ECU.

2) Check for back out of pins at both Alternator Terminal –

and ECU connector.

3) Check for damage of pins at both Alternator Terminal -

and ECU connector.

4) Check the continuity from Alternator Terminal -

to the ECU pin.

5) Alternator Functional?