Vehicle Diagnostics and Troubleshooting with OBDII

1. AN
ORAL PRESENTATION
ON
STUDENTS’ INDUSTRIAL WORK EXPERIENCE
SCHEME
UNDERTAKEN AT
HEPHZIBAH AUTOCARE LIMITED.
AT AKAD FILLING STATION,ALONG FUTA NORTH
GATE AKURE,ONDO STATE.
COMPILED BY : IBIRONKE DOTUN S.
MATRIC NUMBER : MEE/17/3349.

2. OUTLINE
 ABOUT THE ORGANIZATION
 EXPERIENCES GAINED
 SCANNING OF VEHICLES USING OBD-II SCANNER
 DIAGNOSTIC TROUBLE CODES (DTC CODES)
 INTERPRETATION OF DTC CODES
 PRACTICAL EXPLANATION OF A DIAGNOSTIC CODE
 REASONS WHY A VEHICLE MIGHT FAIL TO START
 CONCLUSION AND REOMMENDATION

3. ABOUT THE ORGANISATION
HEPHZIBAH AUTOCARE LIMITED
 Hephzibah Autocare, located at Akad filling station, along FUTA North Gate,
Akure, Ondo State, specializes in servicing various brands and models of passenger
and light goods vehicles, including SUVs, sedans, trucks, and more.
 Established in 2018 by Engr. Opeyemi, Hephzibah Autocare has a dedicated team
of around 5 staff members. Some of their trained personnel have successfully
started their own mechanical firms.
 Hephzibah Autocare is known for its advanced computerized diagnostics, tuning
and programming of Engine Control Units (ECUs) and Powertrain Control
Modules (PCMs), as well as offering services like key programming, alarm
installation, and Transmission Control Module (TCM) expertise.

4. ORGANOGRAM OF THE COMPANY

5. EXPERIENCE GAINED
 VEHICLE SCANNING.
 VEHICLE DIAGNOSIS.
 VEHICLE MAINTENANCE.
 VEHICLE ELECTRICAL REPAIRS.

6. SCANNING OF VEHICLES USING
OBD-II SCANNER
 OBD-II scanners follow a universal system implemented in vehicles since
1996, ensuring consistent and reliable diagnostic capabilities across various
vehicle brands and models.
 OBD-II scanners offer features like clearing codes from the vehicle's memory
and displaying real-time sensor data, aiding in effective troubleshooting and
monitoring.
 OBD-II scanners retrieve and interpret Diagnostic Trouble Codes (DTCs),
which are alphanumeric codes indicating vehicle malfunctions.

7. DIAGNOSTIC TROUBLE CODES
(DTC CODES)
 DTC codes are alphanumeric codes generated by a vehicle's onboard
computer systems to indicate malfunctions or issues within specific systems
or components.
 A typical DTC has five characters in total, and each one of those characters
gives a specific description.
 DTC codes help streamline the troubleshooting process by providing a
starting point for technicians to investigate and resolve the underlying issues
affecting the vehicle's performance.

8. INTERPRETATION OF DTC CODES
The First Character (Letter)
 "P" codes refer to Powertrain issues, including engine, transmission, and emissions-
related problems.
 "C" codes relate to Chassis or body-related issues.
 "B" codes pertain to Body-related issues such as airbags, climate control, or lighting
systems.
 "U" codes indicate network communication problems within the vehicle's systems.
The Second Character (Number)
The first letter is usually followed by a number. This number can only be ‘0’ or ‘1’.
0 – If it’s a ‘0’ then the code is a standardized (SAE) code; also known as generic code
1 – If it’s a ‘1’ then it is a manufacturer-specific code

9. INTERPRETATION OF DTC CODES
The Third Character (Number)
The third character is another number hat ranges from 0-7
0 – Fuel and air metering and auxiliary emission controls
1 – Fuel and air metering
2 – Fuel and air metering (injector circuit)
3 – Ignition systems or misfires
4 – Auxiliary emission controls
5 – Vehicle speed control and idle control systems
6 – Computer and output circuit
7 – Transmission.
The Fourth And Fifth Characters (Number)
The fourth and fifth characters are read together as a two-digit number between 0-99 known as the specific
fault index. These characters identify the exact issue of the vehicle

10. PRACTICAL EXPLANATION OF A
DIAGNOSTIC CODE
Diagnostic Code: P0420
 Letter: P (Powertrain): Indicates the fault is related to the engine or emissions control system of the vehicle.
 First Digit: 0 (Generic): Denotes that the code is a generic OBD-II code applicable to various vehicle makes
and models.
 Second Digit: 4: Indicates that the fault is related to the emissions control system.
 Last Two Digits: 20: Specifies the specific issue within the emissions control system.
 Issue: The code signifies a potential problem with the catalytic converter's efficiency. It suggests that the
catalytic converter may not be functioning optimally, potentially due to a failing catalytic converter, an oxygen
sensor malfunction, or an issue with the exhaust system.
WHAT REPAIRS CAN FIX THIS FAULT?
 Oxygen Sensor Replacement
 Catalytic Converter Replacement
 Exhaust System Repair Engine Tune-Up

11. REASONS WHY A VEHICLE MIGHT
FAIL TO START
 AIR
 SPARK
 FUEL

12. CONCLUSION AND REOMMENDATION
CONCLUSION
My attachment at Hephzibah Autocare has been an invaluable experience, providing extensive
knowledge and practical exposure in automobile diagnostics and repairs. Working alongside skilled
experts, I conducted experiments, gained fresh perspectives, and enhanced my practical skills.
RECOMMENDATION
I recommend stricter supervision of trainees, partnerships between ITF and companies, government
encouragement of the training scheme, assistance from educational institutions in securing placements,
and advocating for remuneration for students to cover transportation expenses

14. THANK YOU FOR LISTENING!!