Tools to survive and thrive

John Batten takes a look at the art of diagnosis and the one tool to rule them all

Published:  11 June, 2018

My life as a business owner, trainer and technician is an interesting one. I was recently spending some time with a client after a course just shooting the breeze. You know the kind of thing, a cuppa, a cake and an hour just putting the world
to rights.
Part way through our conversation Matt proclaimed that I must be “living the dream!” This made me stop and think (something I’ve been told not to do by my wife) about how I am indeed very fortunate to have a career doing something I truly love.

Wading through treacle
Spending my days with like-minded business owners and technicians, helping them drive their careers and businesses forward. What’s not to like about that? Not much, but has my work life always been like skipping through meadow on a sunny day?
Quite frankly… No! Don’t get me wrong –  I’m a glass half full sort of chap and regardless of the task ahead I’ll give it my best and persevere until success emerges. However, on many occasions in my diagnostic career it was just like wading through treacle, and therein lies my point. To get to a place where you’re ‘living the dream’ you need wellies! Show me a successful technician and I’ll show you someone who’s great at wading. They’ve just waded long enough to build a versatile skill set along
the way.

The recipe for success
As with most things in life there are essential ingredients. With the right ingredients you’ll successfully avoid the diagnostic treacle swamp and swap this for a faster and more enjoyable repair experience.
“What’s this recipe?” I hear you cry. It has six elements that when bought together produce truly remarkable results. They are;

  •  The right technician
  •  The right tools
  •  The right information
  •  The right training
  •  The right practice
  •  The right process

The focus of this month's article being the right tools for your diagnostic survival.
I could turn this entire magazine into ‘Johnny’s must-have tool guide.’ However, instead I’ll focus on the
one tool that plays a huge part in troubleshooting success; Enter the oscilloscope.
Why am I so fond of this tool? When used skillfully it will quite simply change the way you look at diagnosis forever. I was speaking with Kris Gordon of Pier Garage (one of our training delegates) about this recently. He’s been making some great progress with his fault-finding career and mentioned that use of a scope and some practice has enabled him to “be able to mentally visualise what he should be seeing and the state of the circuit.” This is a sure-fire route to a successful and timely diagnosis. It just so happens that I made a similar discovery in my own career many years ago. Perhaps we’re onto something? But which scope should I buy?

Getting ready to dodge the Bullet
If there was ever a contentious subject it is “which is the best scope to buy?” Wars have been fought over less and in some parts of the world that battle still continues between the diehards in the red camp and the blue camp. I take a slightly more pragmatic approach. Let me ask you a question; How many ways do you have of undoing a 15mm nut? Take a look in your toolbox you’ll find dozens of ways to achieve that task. Why so many options? Different tools for different jobs and in many ways scope choice is no different.

The Search for the Grail
Like Indiana Jones I’ve been searching for the Holy Grail of scopes my whole career and I’m yet to find ‘The One’. What does my Grail scope look like?

  1. Minimum of four channels. Eight would be very cool
  2. The capability to easily build a waveform database
  3. Sufficient hardware specification; bandwidth, record length, samples, waveform update rate etc to accurately display fast frequencies over longer time bases
  4. Great software; A range of triggers, math channels, cursors, ignition analysis etc which will enable me to be creative with my test techniques
  5. Highly portable so I can move quickly and freely around the vehicle without the need to carry a laptop or push a trolley

If by chance you’ve found this illusive tool then I’d be grateful if you’d let me know, until then I’ll continue to use two scopes. A PC based scope for points one through four and a handheld for when portability is key or I need to invert myself in a footwell.

It’s worth bearing in mind that as the “one scope to rule them all” is yet to be discovered then you may need more than one to cover all bases.

I own a Scope – What next?
This is where the magic happens. They key here is to find a little time to practice and look at good waveforms. This, along with the most important questions you’ll ever ask;  “Why does that waveform look that that?" Followed up with a little training or research to discover the answer will propel your career to another level.
Take a look at the following example and I’ll talk you through the salient diagnostic points. Waveform 1 is a primary ignition waveform from a BMW 3 series. I’ve made a single connection to switched side of the coil with a full range voltage scale of 500 volts with 10ms across the screen. Let’s take a look at all the diagnostic information we can see from just one connection.

  1. Battery voltage. This confirms fundamental continuity of the positive supply. It is worth noting that as the circuit isn’t loaded at this point, a high resistance in this part of the circuit may not be visible. Another channel testing the coil supply would fix that though

  2. Coil turn on. The ECU has grounded the primary winding and current will start to flow in the primary. Dwell starts here

  3. Dwell time. This is the duration that the primary winding is held to ground. A magnetic field will be building, enveloping the primary and secondary windings. It’s useful to compare dwell across all coils. Discrepancies can indicate primary circuit faults and even ECU output stage issues

  4. End of Dwell. The control unit no longer holds the primary circuit to ground. The magnetic field produced in the dwell phase collapses inducing a voltage in both primary and secondary windings. This can reach many hundreds of volts. Discrepancies here are indicative of primary circuit faults

  5. Ignition burn time. I know you shouldn’t have a favourite, but this is my favourite part of the waveform. Here you can see the effect of mutual induction between the primary and secondary windings. The shape (for want of a better word) in this part of the waveform is indicative of so many variables within the cylinder. Items like plug gap, compression, mixture, cylinder sealing to name but a few

  6. Coil oscillations. At this point we no longer have enough energy to maintain the spark, the event ending with oscillations. This can be indicative of secondary issues

All of that and form just one connection. What’s more, I’m not finished yet. For waveform 2 I’ve changed the voltage scale to two volts full range. This enables me to gain additional diagnostic information from the same waveform.
Points 7 and 8 are the start and end of dwell, the ramp between them caused by the increase in current within the primary winding (I do love ohms law). Discrepancies here indicate faults within the primary circuit.
In summary, one quick connection and eight points of diagnosis that will increase not only the speed of fault identification, but will give additional certainty when it comes to root cause analysis. All this and I’ve only used one channel. Wait until you see what we can do with a few more!
If you’d like to know more about how to develop your technical team then call John at Auto iQ on 01604 328500. Alternatively why not attend one of our free online training events. To find out more visit.

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  • Would you like to diagnose more vehicles first time? 

    As we reach March, 2019 is well and truly underway. In fact by the time you read this one third of the year will have whizzed by never to be seen again. Now, I’m not one for New Year’s Resolutions (they’re so last year), but I am the type of chap that likes constant progress when it comes to developing a technician’s career.
    There’s so much to be said for small steps taken everyday that on first look appear don’t appear to make a difference, but when gazed back upon over a 12 month period have a staggering affect on your capability to diagnose a vehicle first time, in a timely manner.

    Pitter-patter of tiny feet
    Small steps are all well and good but where do you start? After all, you don’t know what you don’t know, and you’d like to start your journey to diagnostic success off on the right foot. In this instance I’d start with the end in mind and reverse engineer the outcome you desire. It’s a logical process that works, and can be replicated time and time again in your diagnostic routine.
    Your ‘end in mind’ in this instance is a vehicle where the fault no longer exists, that won’t appear back across the threshold of your workshop anytime soon. But how do you guarantee that?

    One test to rule them all
    I love nothing more than when the delegates working through our training programs have a technical epiphany. This happens at many points on their path of learning, but none more than with bypass testing.
    Bypass testing is step nine in Johnny’s diagnostic circle of love (our 15 step routine), and often the key element in the first time fix. The good news for you is that it doesn’t require mythical creatures to forge their magical powers into an object that only one technician can possess. It’s something that every tech can learn, and become a diagnostic wizard.

    What is bypass testing?
    Quite simply it’s fixing the vehicle before you fix the vehicle. Let me explain.
    Wouldn’t it be great if you suspected that a Mass Air Flow sensor was at fault and you could prove that you were right before you fitted a new part, or spoke to the owner of the vehicle. If you could do that then the positive effect it would have on you and the business you work for would blow you away.
    Picture this: Your customer has reported that the vehicle is low on power. You’ve diligently questioned them, experienced the problem with them on a road test, and the bought the vehicle into the workshop.
    You’ve pulled codes and found none present, followed by taking a look through serial data to hunt for diagnostic clues. It doesn’t take you long to identify that the MAF sensor frequency looks a little low at 1.5 Khz and your fuel trim data is incorrect and making a positive corrections. You’ve seen a bunch of these before and know that 1.85 Khz is a suitable value for this vehicle.
    You’re keen to prove that the serial data is leading you in the right direction so confirm the sensor output with your oscilloscope. The oscilloscope frequency mirrors that of the serial tool and your starting to get that warm fuzzy feeling that an you’re onto something.

    Steady the buffs
    You’ve been close to success before though, only to be thwarted in the final moments so you’re keen not to be caught out twice. You know that documenting the reasons that the MAF output could be incorrect is the way to go, and duly make a list of tests required to confirm your theories.

  • part ONE: ‘You owe me!’ 

    As an employer, have you ever found yourself in a situation where you need to make a deduction from an employee’s wages? Are you confident that you know the legal rules in this area? Andrew Rayment, a Partner in the employment department of law firm Walker Morris, has seen this question arise many times with employers who have made the wrong decision.
    He offers an example to illustrate the point. A worker has had to take three weeks off work because of a bad back. He is paid statutory sick pay but there is no company sick pay scheme to top this up. He has three young children to support and the employer knew he was going to struggle to make ends meet. The employer ‘topped him up’ to his full wages for the three weeks as a ‘loan’ to help him out. It was agreed, however, that the loan was to be repaid when the worker was in a better situation. The payment was through payroll so the money was received as ‘wages’.
     “The problem in this case was that everything was done on trust, so nothing was written down or confirmed in writing,” and as Andrew continued, “a year later the worker resigned after a disagreement. During the interregnum, the period between handing in his notice and his departure, he didn’t repay the money, so it was simply deducted from his final wages payment.” The agreement for the loan was verbal and there was nothing written into his employment contract for the employer to make deductions from his wages.
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    What does the law say?
    Section 13 of the Employment Rights Act 1996 sets out the provisions that protect workers from unauthorised deductions (known as unlawful deductions) being made from their wages.
     “Quite simply,” says Andrew, “the law says it is unlawful for an employer to make a deduction from a worker's wages unless the deduction is required or authorised by statute or a provision in the worker's contract; or the worker has given their prior written consent to the deduction.”
    Worse still for employers, he says that unlike breach of contract claims which can only be brought after the employment has ended, employees can bring unlawful deductions claims in the Employment Tribunal while their employment is ongoing.

    Who is protected?
    The law applies to all workers and includes not only an employee, but an individual who has entered into ‘any other contract... to do or perform personally any work or services’, unless the individual is carrying on a ‘profession or business undertaking’ and the other party to the contract is ‘a client or customer’ of that undertaking. In practice, anyone who is on the payroll regardless of whether they are full-time, part-time, casual, direct agency hire or zero-hours will be protected.
    Andrew cautions employers that following a raft of recent cases on worker status many self-employed contractors may be deemed in law to be workers regardless of the parties’ intentions or the contractual paperwork.
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    Techs wanting to take part in Top Technician 2019 have until 23.59 tomorrow (Friday 4 January) to take the round one quiz, or risk missing out on the competition this year.

  • Do you have a business or a profitable job? 

    It’s a favourite of mine, and one we ask of all garage owners that join the Auto iQ business development programme...
    “Do you have a business or a profitable job?” Not sure which one you’ve got? Carry on reading.
    That question is a doozie and is often met with a few seconds of silence followed by a mixed range of answers whilst the questionee arranges their thoughts. The question is designed to be thought-provoking and entice the garage owner to work through the differences between the options.

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    What’s the difference between a profitable job and a business? It’s a fine line with a BIG difference.
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    I can feel the tension elevating as some of you may be rising from you chair ready to give me a good talking-to. Hang fire though and hear me out. In no way am I saying that having a profitable job is wrong. Quite to the contrary. If that’s what you set out to achieve then who am I to say any different? Here’s the deal though. Most garage owners don’t embark on this amazing journey to be ‘self employed,’ they do it to build a bigger and better future for their families. They did it to have more time with their loved ones, the funds to allow this and probably have early retirement thrown in with the business providing the income. Can a profitable job do this or do you need a business that’ll run without you? I think you know the answer.

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    Our business owner also has a laser-like focus, his target is a little different though. His gaze is firmly fixed on a vision of the business he’s building and knows that long term success requires not only focus but patience. He’s acutely aware of the one thing that will bring freedom and the time with his family (the reason he started this venture) is the team he builds and trains.
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    Dominant thoughts
    It’s a proven fact that we all move through our day in the direction of most dominant thoughts. What does your typical business owner ponder?. Now I can’t read minds (how cool would that be?) but I do know that these are the questions that need to be answered:

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