Initially, venturing into the realm of automotive diagnostics, a budget-friendly $50 Harbor Freight OBDII scanner proved to be a surprisingly effective tool for basic shop tasks. Its utility sparked a desire for a more continuous monitoring solution while driving. This led to the acquisition of a generic ELM327 Bluetooth OBDII dongle, a cost-effective option priced under $20, which seamlessly paired with a Nexus 7 and Android phone using freely available software.
However, it’s worth noting that Bluetooth ELM327 dongles encounter compatibility issues with Apple products due to iOS Bluetooth restrictions. For iPhone or iPad users seeking similar functionality, a Wifi OBDII dongle becomes necessary. Experimenting further, a Wifi OBDII dongle was also procured and successfully tested with both an iPhone and iPad, utilizing various complimentary applications. These initial experiences highlight the accessibility and affordability of basic OBDII scan tools like the Cen-Tech Deluxe Scan Tool, often found at Harbor Freight. While perhaps not as feature-rich as more advanced options, these tools provide an entry point for DIY car diagnostics.
For a more permanent in-car OBDII monitoring setup, the UltraGauge wired unit was selected, priced at $80 (though recalled as being slightly cheaper previously). Although a wireless version for smartphone integration is available from UltraGauge, the preference was to avoid dedicating a phone solely for this purpose during trips. The UltraGauge was configured to display essential real-time data such as digital speed, instantaneous MPG, trip MPG, remaining fuel in gallons, miles to empty, and coolant temperature. While some of this information is accessible via the instrument cluster and onboard computer, the UltraGauge offers the advantage of simultaneous viewing of multiple parameters. Its customizable display can be configured with up to 8 readings per page and supports up to 7 pages, with a preferred layout being the 6-reading display which balances two larger and four smaller readouts for optimal readability.
A significant benefit of digital coolant temperature monitoring, as provided by tools like the UltraGauge and even basic scan tools, is its precision compared to traditional analog gauges. The coolant temperature dial on many instrument clusters often exhibits non-linearity and compression within the typical operating temperature range. With a digital readout, the precise temperature fluctuations become apparent, allowing for observation of thermostat operation and overall cooling system performance.
Beyond real-time monitoring, OBDII scan tools, including entry-level options and more advanced devices, also provide diagnostic capabilities. They enable reading and clearing diagnostic trouble codes (DTCs). While basic tools may display codes numerically, requiring smartphone lookup for text descriptions, this functionality proved invaluable in a real-world scenario. When facing a transmission failure in a relatively new Nissan Altima, the UltraGauge quickly revealed a P0750 code. A swift online search identified it as a transmission solenoid issue, enabling a call to the dealership with specific information. The dealership, familiar with this problem, promptly arranged towing, a rental car, and expedited service, demonstrating the practical benefit of even basic DTC reading capabilities in diagnosing car problems and facilitating efficient communication with repair services.
