the automaker, runs on your shop PC or laptop, and can either be web-based or CD- based. The subscription fees are charged differently for each automaker. Some automakers such as GM charge an annual fee for full access, while others have options for paying: per-vehicle, daily, weekly, monthly, or annually. Many of these services also include bonus features beyond flash reprogramming. FMP from Ford lets repair shops reprogram transponder keys, and other automakers are beginning to support diagnostic functionality. Figure 1 shows the website for each automaker’s service and fees.
Hardware The second part of the system is a J2534-1 compliant PassThru vehicle interface. This box or cable acts as a gateway between the vehicle’s onboard computers and the technician’s personal computer. It translates messages from the PC into the protocols used by the automobile and vice versa. A Drew Tech J2534 tool is pictured in Figure 2 to give you an idea of what a PassThru interface looks like.
Common PassThru devices connect your PC to the vehicle using USB, serial, Ethernet, or wireless. The easiest to configure is probably USB, but Ethernet has the longest range and highest performance. You can double the distances on USB connections by adding a hub between your PC and PassThru tool. Wireless has also become popular with both Bluetooth and 802.11 options being offered by different tool vendors. The 802.11 technology offers a higher bandwidth and distance range, but typically costs more than a Bluetooth option. Figure 3 illustrates the benefits of each connection type and highlights the option best for each characteristic. The CarDAQ-Plus from Drew Technologies (www.drewtech.com) and the E-Flash from ATS (www.automotivetestsolutions.com) are currently the only PassThru tools offer Ethernet, USB, and an upgrade path to 802.11 wireless all from one device.
There are a number of PassThru tools for sale in the market, all at different prices with different features, performance, and customer support. The primary function of a PassThru device is to support the automaker’s subscription service for reprogramming. Picking a device that is fully compliant to J2534-1 is important, but many bonus features may make certain brands more attractive. Some offer additional features such as generic scan tool software, enhanced diagnostics software, and analog scope inputs.
Performing J2534 reprogramming requires computer knowledge and experience. The technician will need to operate a laptop or desktop, the PassThru device, and the reprogramming software. Operation will also require a good high-speed connection to the Internet such as DSL, Cable, or T1.
Non-compliant Devices Because J2534-1 is an SAE standard, all PassThru tools should be the same; but in reality not all devices are fully compliant to J2534-1 or work with all vehicles. You should shop carefully when picking a device, and look at functionality and compliance before shopping on price alone. Be sure to get one that is guaranteed by the manufacturer to be fully compliant and that has been validated by the automakers you plan to service. None
Drew Technologies, Copyright 2009