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A professional car diagnostic tool does more than just read and clear trouble codes. It also comes with many special functions that can significantly improve repair efficiency. These functions save time, increase accuracy, and allow you to perform tasks that are difficult or impossible without the right tool.
This guide will walk you through 20+ common special functions, explaining their purpose and when to use them so you can get the most out of your diagnostic tool.
Brake & Chassis Functions
ABS Bleeding (Anti-lock Braking System Bleeding)
🔹 Function: When air gets into the brake system, it can cause soft or ineffective braking. The ABS Bleeding function activates the ABS pump and solenoid valves to help remove air from the brake lines, ensuring stable and responsive braking.
🔹 When to Use: After replacing brake fluid, brake calipers, brake lines, or performing ABS system repairs.
🔹 Function: When air gets into the brake system, it can cause soft or ineffective braking. The ABS Bleeding function activates the ABS pump and solenoid valves to help remove air from the brake lines, ensuring stable and responsive braking.
🔹 When to Use: After replacing brake fluid, brake calipers, brake lines, or performing ABS system repairs.
EPB Reset (Electronic Parking Brake Reset)🔹 Function: The EPB system requires special tools to release or reset, making it easier to replace brake pads or repair the parking brake system.
🔹 When to Use: After replacing brake pads, fixing parking brake issues, or when the parking brake warning light is on.
🔹 When to Use: After replacing brake pads, fixing parking brake issues, or when the parking brake warning light is on.
SAS Calibration (Steering Angle Sensor Calibration) 🔹 Function: Misalignment between the steering wheel and wheels can cause drifting or a crooked steering wheel. This function recalibrates the steering angle for precise control.
🔹 When to Use: After wheel alignment, steering system repairs, or when the steering wheel is misaligned.
🔹 When to Use: After wheel alignment, steering system repairs, or when the steering wheel is misaligned.
Suspension Adjustment 🔹 Function: Vehicles with air suspension can adjust ride height for better comfort or handling.
🔹 When to Use: When modifying ride height or troubleshooting suspension issues.
🔹 When to Use: When modifying ride height or troubleshooting suspension issues.
Engine & Emission Control Functions
DPF Regeneration (Diesel Particulate Filter Regeneration) 🔹 Function: The DPF traps carbon particles in diesel exhaust. Over time, it gets clogged. The DPF Regeneration function heats up and burns off carbon deposits, restoring normal exhaust flow.
🔹 When to Use: When there are abnormal exhaust emissions, reduced engine power, or the DPF warning light is on.
🔹 When to Use: When there are abnormal exhaust emissions, reduced engine power, or the DPF warning light is on.
Injector Coding 🔹 Function: Fuel injectors control fuel delivery, and their characteristics vary. After replacing or cleaning injectors, they must be recalibrated to ensure precise fuel injection, reducing fuel consumption and improving performance.
🔹 When to Use: After replacing injectors, when experiencing engine vibration, or increased fuel consumption.
🔹 When to Use: After replacing injectors, when experiencing engine vibration, or increased fuel consumption.
A/F Set (Air-Fuel Ratio Adjustment) 🔹 Function: Optimizes the fuel and air mixture for better fuel efficiency and performance.
🔹 When to Use: When dealing with excessive carbon buildup or increased fuel consumption.
🔹 When to Use: When dealing with excessive carbon buildup or increased fuel consumption.
Urea Set (DEF System Reset) 🔹 Function: Diesel vehicles use DEF (Diesel Exhaust Fluid) to reduce emissions. This function clears system errors and recalibrates DEF injection parameters.
🔹 When to Use: When the DEF warning light is on.
🔹 When to Use: When the DEF warning light is on.
NOX Set (NOx Sensor Setting) 🔹 Function: Adjusts the nitrogen oxide emission control system to meet environmental standards.
🔹 When to Use: After emission system repairs or when exhaust emissions are excessive.
🔹 When to Use: After emission system repairs or when exhaust emissions are excessive.
Pump Start (Fuel Pump Activation) 🔹 Function: Controls fuel pump operation to ensure proper fuel delivery during engine startup.
🔹 When to Use: After replacing the fuel pump or fixing fuel system issues.
🔹 When to Use: After replacing the fuel pump or fixing fuel system issues.
Key & Security Functions
IMMO Keys (Immobilizer Key Programming)🔹 Function:Modern car keys contain anti-theft chips. A new key must be programmed to match the immobilizer system, or the car won’t start.
🔹 When to Use: When adding a new key or replacing lost keys.
🔹 When to Use: When adding a new key or replacing lost keys.
Door & Window Control 🔹 Function: Fixes window operation issues and adjusts door lock settings.
🔹 When to Use: When windows or doors are not functioning properly.
🔹 When to Use: When windows or doors are not functioning properly.
Start & Stop 🔹 Function: Allows you to disable the auto start-stop system or set it to remember the last used state.
🔹 When to Use: When you want to turn off the start-stop function or retain the previous setting.
🔹 When to Use: When you want to turn off the start-stop function or retain the previous setting.
Transmission & Tire Functions
AT Setting (Automatic Transmission Setting) 🔹 Function: Adjusts shift logic in automatic transmissions to suit different driving habits or repair needs, enhancing smooth shifting.
🔹 When to Use: When experiencing harsh shifting or gear hesitation.
🔹 When to Use: When experiencing harsh shifting or gear hesitation.
Gear (Transmission Control) 🔹 Function: Reads or adjusts transmission settings to optimize shift timing, acceleration, and fuel efficiency.
🔹 When to Use: After transmission repairs or fluid changes.
🔹 When to Use: After transmission repairs or fluid changes.
Tire Set ( Tire Setup)
🔹 Function: When replacing tires with a different size, this function adjusts vehicle parameters to ensure accurate speedometer readings and maintain driving stability.
🔹 When to Use: When installing tires of a different size.
🔹 Function: When replacing tires with a different size, this function adjusts vehicle parameters to ensure accurate speedometer readings and maintain driving stability.
🔹 When to Use: When installing tires of a different size.
Transport Mode 🔹 Function: New vehicles are shipped with some electrical functions disabled to preserve battery life. This mode must be turned off upon delivery.
🔹 When to Use: Before or after new vehicle delivery.
🔹 When to Use: Before or after new vehicle delivery.
Electronic & Comfort Functions
Headlight Adjustment 🔹 Function: Adjusts headlight height, brightness, or enables automatic headlight functions for safer night driving.
🔹 When to Use: After replacing headlights or adjusting beam angles.
🔹 When to Use: After replacing headlights or adjusting beam angles.
Sunroof Initialization 🔹 Function: Reinitializes the sunroof to ensure proper operation.
🔹 When to Use: When the sunroof won’t open/close properly or after replacing the motor.
🔹 When to Use: When the sunroof won’t open/close properly or after replacing the motor.
TPMS Reset (Tire Pressure Monitoring System Reset)🔹 Function: Resets TPMS sensors to ensure accurate tire pressure readings after maintenance or changes.
🔹 When to Use: After installing new sensors, changing tire positions, or switching between seasonal tires.
🔹 When to Use: After installing new sensors, changing tire positions, or switching between seasonal tires.
Throttle Reset (Throttle Position Reset) 🔹 Function: The throttle controls airflow into the engine. Over time, carbon buildup can cause sluggish throttle response. This function recalibrates throttle position, improving acceleration response.
🔹 When to Use: When experiencing delayed throttle response, unstable idle, or after cleaning the throttle body.
🔹 When to Use: When experiencing delayed throttle response, unstable idle, or after cleaning the throttle body.
Oil Reset🔹 Function: After an oil change, the system needs to be reset; otherwise, the dashboard may continue displaying the “Change Oil” warning.
🔹 When to Use: After an oil change.
🔹 When to Use: After an oil change.
Conclusion & Tool Recommendation
Mastering these special functions allows you to work more efficiently and accurately when it comes to vehicle maintenance, troubleshooting, and repair. Whether you are a professional mechanic or a DIY car enthusiast, a diagnostic tool with these advanced functions can make your job much easier.
If you’re looking for a diagnostic tool that supports most of these special functions, check out our ANCEL professional diagnostic tool series. These tools not only provide full OBDII capabilities but also integrate powerful special functions to handle a wide range of repair scenarios.
👉 Click here to explore the full ANCEL diagnostic tool lineup.
