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: 781 of 1052
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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.
P0266-2B: Cylinder 2 Injector Circuit High – Short circuit between high side and low side of the power stage
cylinder 2
Overview:
DTC Description (User Friendly)
Short circuit between high side and low side of the power
stage cylinder 2
ECU Pin Number
A43, A22
Customer Symptom
Torque Limited, Cruise Control Off, MIL ON, Abnormal Engine
noise
Fault Effects (On Vehicle)
Reduced torque mode activated, Cruise control off, Abnormal
Engine noise
Lamp Status (If Any)
MIL ON
Fault Detection Condition (Root cause)
Short Circuit btw EMS ECU pins A43 and A22.
Normal Operating Condition
From fault, normal operating condition will be achieved in the
next driving cycle if fault condition is no more present.
Probable Trouble Area
Wiring Harness connections between EMS ECU and Injector
cylinder 2
Injector Cylinder 2
EMS ECU
Healing Condition
Rectify the error
Clear through diagnostic tool
Ignition OFF & ON
Component Details:
Injector is used for, Metering and spray preparation of the diesel fuel, which is needed by the engine
according to the engine map.Realization of pilot and main injection, also post injection, if needed Controlling of injected
quantity and injection timing, determined by system pressure and energizing time, actuated by the ECU (Electronic
Control Unit).
Preliminary Checks:
1. Check whether the customer voice / view about the issue is matching with the fault effects mentioned in above
Table. If yes, go ahead with next steps. If not, check for other DTC’s presence.
2. Check whether other customers report similar complaints earlier. If yes, perform the preliminary checks with
respect to earlier issue closure.\
3. Check the wiring harness connections between EMS ECU and Cylinder 2 Injector as per the circuit Schematic.
4. Loose/ Damaged Connections between Cylinder 2 Injector and EMS ECU.
5. Check for damage of pins at EMS ECU connector and Injector Cylinder 2 connector.
Trouble Shooting:
Step Checks
IF YES
IF NO
1
Check for any mechanical damage in Cylinder 2 injector
Call Hotline
Go to next step
2
Is there wiring harness electrical continuity between ECU
pin A43 & Cylinder 2 Injector connector pin 2, ECU
pin A22 & Cylinder 2 Injector connector pin 1.
Go to next step
Rectify the wiring
harness
connections as per
the circuit
schematic.
3
Check whether the EMS pin A43 is short-circuited to EMS
ECU pin A22.
Rectify the wiring
harness connections
Go to next step




