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Q501 4 Cylinder MT Application
DTC Troubleshooting Data
Version: 0.1
Date: 21-Sep-2018
Prepared By: Mithi Prasad, Sarang Kulkarni, Manish Gupta
Checked By: Yogesh Jadhav
Approved By: Satish Kumar P
Page: 710 of 1052
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.
P0120-13: Throttle / Pedal Position Sensor / Switch “A” Circuit– Diagnostic fault check to detect unplugged error
for accelerator pedal sensors
Overview:
DTC Description (User Friendly)
Diagnostic fault check to detect unplugged error for
accelerator pedal sensors
ECU Pin Number
K041, K025, K024, K07, K027, K026
Customer Symptom
MIL ON, No Acc. Pedal Response
Fault Effects (On Vehicle)
No Pedal Response, Engine Idle RPM raise, Cruise Control
Off
Lamp Status (If Any)
MIL ON, CEL OFF
Fault Detection Condition (Root cause)
Accelerator Pedal sensor dis-connection.
Normal Operating Condition
No Fault Code
Probable Trouble Area
Accelerator pedal Sensor Connector, Wh connections btw
ACc Ped sensor and EMS ECU, Accelerator Pedal Sensor,
EMS ECU
Healing Condition
Rectify the error
Clear through diagnostic tool
Ignition OFF & ON
Component Details:
For safety reasons, the accelerator pedal sensor is equipped with 2 resistors (potentiometers) with varying operating
ranges (~2.23 – ~ 4.45 V and ~ 0.38 – ~ 2.23 V) and separate circuits. A potentiometer informally a pot, is a three-
terminal resistor with a sliding contact that forms an adjustable voltage divider. If only two terminals are used, one end and
the wiper, it acts as a variable resistor or rheostat. Based on the Accelerator pedal position, Engine will produce the driver
demanded torque based on the accelerator pedal position.
Preliminary Checks:
1. Check whether the customer voice / view about the issue is matching with the fault effects mentioned above. If
yes, go ahead with next steps. If not, check for other DTC’s presence.
2. Check whether similar complaints are earlier reported. If yes, perform the preliminary checks with respect to
earlier issue closure.
3. Check for any other faults presence related to ECU Internal power supplies; Follow rectification process for those
faults, before proceeding further.
4.
Check whether the Accelerator pedal sensor connector is broken / dis-connected.
5. Check for Wiring Dis-continuity between Accelerator Pedal Sensor & EMS ECU. If found, fix them
Trouble Shooting:
Step Checks
IF YES
IF NO
1.
Check for any other faults presence related to ECU Internal
power supplies / Accelerator pedal sensor / Brake Pedal
Sensor.
Follow rectification
process for the
faults, before
proceeding further
Go to Step 2
2
Check for electrical continuity between ECU to Accelerator
Pedal sensor connector as per the circuit schematic.
Continuity exists?
Go to Step 3
Establish continuity
by rectifying
harness