Overview

The OBDLink® app can log vehicle data to a CSV file automatically. If logging is enabled, the logged data can be viewed on the Files screen of the Logs menu, and it can be exported for use by an external program of your choice. 

By default, logging is enabled and a CSV file is automatically created when the app is connected to the vehicle. However, you will most likely want to change the logging settings to capture the data that you want.

TABLE OF CONTENTS

• Overview
• Set up log preferences
  • Logging Enabled
  • Logging Trigger
  • Logging Control
  • Select Items to Log
  • CSV File Options
    • Time Format
    • Number of Decimals
• View information while driving
• View log data
  • Graphs
  • Trip Stats
  • Trips
  • Files
  • Messages  
• Need more help?

Set up log preferences

To configure logging, open the Settings > Preferences > Logging page. This screen may look different depending upon the device that you use. Each setting on this screen is described below.

iOS	Android

Logging Enabled

This option enables or disables the logging feature. [Default setting is Enabled] 

When logging is enabled, a new CSV log file will be created automatically each time the app connects to your vehicle.

Logging Trigger

The logging trigger configures when a frame of data is recorded to a CSV file. A single frame of data contains one data point for each sensor being logged. The following options are available:

• Trigger on GPS frame [Default setting] - A frame of data is saved to file when a new GPS reading is captured from your phone or device. GPS readings are usually captured at a rate of one per second. This logging trigger is the most useful when you are using the CSV logs to view data on the Maps screen. If you are exporting the CSV files for use outside of OBDLink, then you might want to consider using one of the other logging triggers.
  Note: If GPS is disabled or your device is not receiving a GPS signal, then there will be nothing to trigger the data logger and a CSV file will not be created. 
• Trigger on PID frame – A frame of data is saved to file when the OBDLink app refreshes each sensor being logged. For example, if vehicle speed, engine RPM, and engine load are being logged to a file, the app will read one sample of each of the three items from the vehicle, then the data will be written to the log file. This logging trigger is useful if you want to export the log files and want to have data points at the same rate as they are read from the vehicle.
  Note: This option provides the fastest sampling rate. 
• Trigger at a fixed sample time – A frame of data is saved to file at a fixed sample time. The sample time is configurable on the Logging screen. In this trigger mode, the OBDLink app keeps track of the most up-to-date frame of data read from the vehicle. When the logging sample time expires, that frame of data is written to a CSV file. This logging trigger is most useful if you want to export the log files and want the data at a constant sample rate.
  Note: If the sample time is faster than the rate at which data is read from the vehicle, you will see multiple rows in the log file with the same data points. 

Logging Control

This option determines whether logging is Automatic or Manual. 

• Automatic [Default setting] - Logging starts when the app connects to the vehicle. 
• Manual - Logging must be started manually using one of these options: 
  • Navigate to Logs > Graphs and tap the Play icon. 
  • Set up a dashboard gauge using the push button style and the action to Start or Stop Logging.
    Refer to the Add and Edit dashboard gauges article for details on how to set up a gauge.

Select Items to Log

This option opens a sub-screen for you to select which PIDs (such as RPM or coolant temperature) you want to record to a CSV file. [Default PIDs are vehicle speed, latitude, and longitude]

If GPS is not turned on, you will be able to select GPS PIDs in this screen, however, no data will be returned.

To search for a particular PID:

• Android: Use the global search function at the top of the list. 
• iOS: Select the PID category (such as SAE PIDs) and search within it.

CSV File Options

Time Format

All CSV log files contain a column with the time at which the frame was captured. The time format option determines whether the time column is written as seconds (from the start of the log) or as a full date and time stamp. [Default is seconds] 

Number of Decimals

This setting determines the number of decimal places used to write data to the CSV file. [Default is Auto] 

By default, the OBDLink app enables trip logging for certain vehicle PIDs (vehicle speed, longitude, and latitude), so you can view log data even if you haven’t changed any of the options described above.

View information while driving

Note: The info presented in the Graphs view is a separate visual representation of PIDs that you select. It allows you to view up to four PIDs while the vehicle is in motion. It is not related to the CSV file PID selections.

Before you begin, be sure to: 

• Start your vehicle and connect your phone/tablet to your OBDLink adapter.
• Make sure your phone/tablet is not streaming to any other Bluetooth/BLE devices.

1. Confirm that your phone/tablet is Connected to the OBDLink adapter.
2. Tap Logs to open the Logs screen. Be sure the Graphs screen is displayed. Tap the Playicon (highlighted) to start logging.

   iOS	Android

   
   
3. The OBDLink app logs two items by default (vehicle speed and mass air flow rate). 

   Tap Menu (iOS) or the Gear icon (Android) to log different items.

   
   

    

We selected Transmission Fluid Temperature as a third item in the iOS example screenshots below.

Before logging started

After logging stopped

View log data

By default, the OBDLink app enables logging for certain vehicle PIDs (vehicle speed, longitude, and latitude), so you can view log data even if you haven’t configured any settings.

Tap Logs in the main screen to open the Logs screen. 

Graphs

This screen is used for live data logging. For details, see the View information while driving section. 

Trip Stats

This screen shows logged information in graph format. 

You can review the data captured on prior trips by swiping right or left (iOS) or by tapping the left or right arrow at the bottom of the screen (Android).

iOS	Android

Tap Item in the upper right corner to change the vertical (Y) axis.

Tap Time in the upper right corner to change the horizontal (X) axis.

You can choose from a predefined list of Item values and Time settings as shown below.

Trips

Every time the app connects to your OBDLink adapter, it captures information. This screen shows basic trip information, similar to a trip counter that your vehicle may have. Tap Reset to reset a trip counter back to zero.

iOS	Android

Files

You will see a list of data logs that were captured for your vehicle (if Logging is enabled).

• iOS: Tap the i icon (highlighted) to view log information for a particular trip. 
• Android: Tap the date and time of the trip you want to view.

iOS	Android

You will see the basic trip information, including start and end time, duration, distance, and file size.

Select one of these options:

• Tap Share to send the CSV file to another app, such as email or a spreadsheet app. 
• iOS only:
  • Tap Open in Maps to see a graphical view of the CSV file, as shown below. The green pin indicates the trip start and the red pin indicates the trip end. By default, the Vehicle speed in MPH is selected.
    Tap Menu > Map Mode in the upper right corner to switch between street map and satellite image views.
    If you selected other PIDs to be logged, tap Menu to view those items. We selected Transmission Fluid Temperature in the second screenshot.
    
    
    
    
  • Tap Open CSV File to see the actual data captured during the trip.
    
    
• Android only:
  • Tap Open to open the selection menu. 
  • Tap Open in Maps to see a graphical view of the CSV file, as shown below. The green pin indicates the trip start and the red pin indicates the trip end. By default, the Vehicle speed in MPH is selected.
    Tap 3 vertical dots > Map Mode in the upper right corner to switch between street map and satellite image views.
    If you selected other PIDs to be logged, you can choose them here.
    
    
    
    
  • Tap Open in Viewer to see the actual data captured during the trip.
    
    

Messages  

This screen is used to capture system log information. If you have issues connecting your adapter, the app should be recording data and it will be displayed here. If a debug log is activated, it will also be displayed here. Read more in the Create a Debug Log article.

Learn more

• The Maps function in the OBDLink app is linked to the Logs function. Read more in the Get Started with Maps article.
• For descriptions of terms used in this article, see the Glossary of Acronyms and Terms. 

Need more help?

OBDLink Support Forum 

Submit a Support Ticket 

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