Stories from the Job Site

	Check the calibration values of the scale, hydraulic boom pressure sensors, and boom position sensor.

When you hear the word troubleshooting, what image immediately springs to mind? Probably a technician spending hours crawling around on a machine with wrenches, screwdrivers, and voltmeters, right? That perception is about to change thanks to the next generation of machine servicing -- onboard diagnostics.

Available on John Deere backhoes, loaders, motor graders, and crawlers, onboard diagnostics eliminate hours of traditional troubleshooting. A wealth of diagnostic information is available right from the machine's monitor, so operators and technicians can frequently tell immediately what system requires attention without a wrench, laptop, or special diagnostic tool.

The major advantage of onboard diagnostics is uptime. "The system pinpoints the problem not only by displaying service codes, but by giving a written description in plain English," explains Bob Tyler, John Deere product marketing manager, backhoes. "Even a novice operator can precisely describe the fault without needing to get the help of a technician."

How it works
Onboard computers continuously check machine systems, including the engine, transmission, cooling, and hydraulics. Temperature-, pressure-, and speed-sensor information is available for the various systems through the machine's monitor. The easy-to-navigate LCD monitor on the K-Series Loader, for example, provides easy, pushbutton access to 11 different parameters for the engine and cooling system alone.

When one of the parameters exceeds limits, a diagnostic trouble code and description are sent to the monitor. In the past when a problem occurred, only a numeric code was generated, requiring the technician to refer to a phone-book-sized technical manual. Not anymore.

The system is also available in Spanish, French, and Russian.

The trouble code identifies the circuit or component where the fault occurred, the type of fault, the computer connected to the component, wire color and number, connectors, and number of occurrences. There's even a reference to the corresponding section in the technical manual, but it's rarely needed because of the thorough diagnostic information displayed right in the monitor.

"Customers love onboard diagnostics because, when they call the dealer with a problem, they can describe it so the technician knows what is wrong before he even comes out," says Bill Loch, instructor, John Deere. "He can bring the right tools and parts with him on the first call without having to diagnose it and then go back for the part. The machine is up and running a lot quicker."

Other advantages
Once repairs have been made, system calibrations can be performed using the monitor. On the J and K-Series Loaders, for example, you can recalibrate the transmission by performing a simple 10-minute procedure. On competitor equipment, a technician must connect to the machine with a laptop and cable to perform a similar task.

Onboard diagnostics can also protect the machine from catastrophic failures. When the engine coolant reaches extremely high temperatures, warning lights and messaging on the monitor alert the operator to the situation, saving the engine from major repairs.

Back to Stories from the Job Site