Newsletter June 2016

BMW ABS Case Study

Steve Smith investigates a BMW 1 Series with a customer complaint of juddering at low speeds.

Customer's description Driving at low speed the vehicle appears to judder, with a yellow warning light illuminated within the instrument panel. The symptom was evident on every drive regardless of temperature and road condition, and had been evident for over a week. Technical description and road test The customer's description of the symptoms was correct and certainly evident during the test drive. The fault proved to be with the traction control operating at low road speed (the yellow warning light reported by the customer was the traction control indicator).

An extended road test at higher speed confirmed that the juddering stopped, but an additional "DTC" warning illuminated within the instrument panel.

Diagnosis

The customer interview confirmed that the vehicle had full service history, no additional accessories installed and no recent repairs. The customer complaint was verified and the vehicle's identification and specification were confirmed.

The basic inspection confirmed visible ABS connections to be secure and the wheel and tire combination to be the correct specification for the vehicle. Tire wear, brand, orientation, condition and pressure were also inspected and confirmed to be correct. This is an overlooked fundamental inspection when diagnosing ABS and traction control faults. The ABS controller monitors the rate of acceleration and deceleration of wheel speed signals to determine if brake pressure intervention is required. Wheel speed signals vary depending upon tire circumference, and in scenarios where tire tread depths, styles and manufacturer differ, there is potential for tire circumferences to vary by 15 mm or more, resulting in differing wheel speeds during straight-line driving. Such a variation in wheel speed signals will have an adverse effect on brake control intervention.

In a perfect world all installed tires should be the same make and specification (and within the same construction date (stamped on the tire wall)) but in reality this is near impossible. We can, however, physically measure tire circumference and tread depths to confirm whether the deviation between tires is within manufacturer specification and eliminate these variables from our diagnosis.

A vehicle scan confirmed ABS fault codes, indicating signal plausibility and a possible concern surrounding the condition of the sensor pick-up (see code 5DC2 below "increment gear")...

To read on and see how Steve was able to correctly diagnose this fault, please see the BMW 1 Series case study on our website.

New videos: Frank Massey's top ten tests

Pico and Frank Massey of ADS Limited have joined forces to bring you Frank's top ten tests with PicoScope.

In video #1, Frank discusses using PicoScope to observe voltage drop against load, measured as current by the consumer. Frank discusses the theory of the test, what is being tested and the simplicity of using a scope for this test. Timebases, voltage ranges, and of course the physical connections required are all covered.

New Master and Maxi kits released

		WPS500X Maxi Kit Our WPS500X Maxi Kit allows you to purchase the WPS500X Automotive Pressure Transducer together with our full set of hoses and adapters, giving you the maximum possible flexibility we can offer. More information on the WPS500X Maxi Kit and its extensive list of parts can be found on our website.
		Master Kit Our Automotive Master Kit contains everything a new user could ever wish for in a PicoScope diagnostics kit. With everything from the Advanced Kit included, and the addition of our new WPS500X Maxi Kit and additional accessories too! Our Master Kit will be available later this month and will appear on our product kits page.

Pico Technology celebrates its 25th Anniversary

On the 1st July 2016, Pico Technology celebrates its 25th year of business.

Pico data loggers, oscilloscopes and signal generators are used by engineers, scientists and technicians around the globe to bring their products to market. Pico automotive diagnostics products help keep the wheels turning for vehicle manufacturers and service organizations on every continent.

1991 was an interesting year. Intel introduced the low-cost 486SX microprocessor, priced at $258. It was implemented on PCs running MS-DOS 5.0 and Windows 3.0. The World Wide Web Consortium was founded by Tim Berners-Lee at CERN, and the GSM mobile network was launched in Europe.

On 1st July Alan Tong and Mike Green co-founded Pico Technology. The company was originally set up as a software consultancy to develop data acquisition solutions using plug-in expansion cards, mostly for customers in the medical industry.

Pico, operating from Hardwick near Cambridge, introduced its first product, the ADC-10, so called because it was an analog to digital converter and sampled at 10 kS/s. It connected to the PC via the parallel port. The first order for ADC-10s was received in August that year, with two units sold for £49 each.

The ADC-10 was the world's first PC Oscilloscope, and in the years that followed Pico notched up several more industry firsts, including the first oscilloscope with digital triggering and the first high-resolution scope.

Today, Pico has over one hundred employees at its head office in St Neots, UK and its subsidiaries in the USA and Lithuania. The company has three divisions producing Test & Measurement, Automotive Diagnostics and Radio Frequency test products that are sold worldwide.

To read on, please visit the news section of our website.

Careers at Pico Technology

Pico Technology is an exciting and innovative leader in the design of PC-based oscilloscopes and data acquisition technology. Our products include PC oscilloscopes, data loggers and automotive diagnostic equipment.

At Pico we believe that employing the right people is more important than fulfilling any specific vacancy, so if the right people are interested in working for us we will consider applications. We are particularly interested in applicants with a technical software background or experience of test equipment design.

If you want to be part of a growing company at the leading edge of test equipment design, why not take a look at our pico.jobs web page and see what we have to offer? We look forward to hearing from you.

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