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: 846 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.

P0812-24: Diagnostic Fault Check for Reverse Gear Position Signal– Signal Stuck High

Overview:

ISO Code

P0812-24

Customer Symptom

In Clutster always observe reverse gear info before error gets registered

and no information of reverse gear on cluster once the error gets

confirmed.

Fault Effects (On Vehicle)

1. No effect on engine starting.

2. No effect on Drivability.

3. There will be no information of reverse gear on cluster.

Lamp Status (If Any)

No Lamp Indication switch

Fault Detection Condition

This fault gets logged if the reverse gear signal/ switch is stuck closed to

high voltage continuously.

Normal Operating Condition

Proper signal from Reverse gear switch to EMS ECU

Probable Trouble Area

Reverse Gear Switch, Wiring Harness Connections

Healing Condition

Engine Running and after 1 Driving 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:

The gear lever engages in reverse gear within the transmission, permitting the vehicle to be driven backward, and

operates a switch to turn on the white lights in tail lamp for improved visibility. Same reverse gear indication signals

goes to EMS ECU to know the vehicle isdriven in reverse direction. Reverse gear digital switch is connected to EMS

ECU by hardware pin.

Preliminary Checks:

1) Loose/ Damaged Connections between Reverse Gear Switch and EMS ECU.

2) Check for back out of pins at both Reverse Gear Switch and ECU connector.

3) Check for damage of pins at both Reverse Gear Switch and ECU connector.

4) Check the continuity from Reverse Gear Switch connector pins to the ECU pins.