Thursday, 31 May 2012 09:33

Diagnosis - The method

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As a Porsche owner, even though you drive one of the worlds most reliable cars, from time to time, a fault may occur. The fault could be just a simple annoyance such as an annoying squeek, or it could be more worrying such as clouds of smoke emitting from your exhaust. In any case, the cause will been to be found and rectified and for that, often you will need to use a garage.

But then there comes a problem on top of a problem, a garage. You already have an issue with your Porsche, and then you have the worry of how much might it cost? Will the garage be honest, or will they take advantage of me? This combination of problems can focus together to make you feel worried, stressed and perhaps even a touch of synicism about what the garage may say before you even get to the garage.

At JMG Porsche we see this kind of problem very often. A customer arrives and seems very annoyed and perhaps combative, even before we have had a chance to diagnose their fault, sometimes a customer may even be reluctant to authorise diagnostic proceedures, feeling that somehow we are proposing a diagnosis which is more lengthy than it needs to be.

From our side, the cars arrive as an unknown, experience tells us that we will find the cause of the problem, but we do not know how much time to set aside to diagnose the issue within our schedule, sometimes the fault can be intermittent, which causes us to worry if we will even see the fault first hand, and sometimes the customers description of the fault can be vague and needs interpretation, it is amazing how often we find the cause of a fault and explain to a customer, only to be told "Oh, maybe I should have said that it only started since driving through a flooded road...", But this is all part of the job at JMG Porsche.

As a Porsche owner, you can rely on your Porsche to stop without skidding in an emergency, you have computerised climate controls to keep you at a constant comfortable temperature, your seats electronically move for your comfort, the engine is controlled by a computer to make it efficient and powerful, there are hundreds of sensors, motors, actuators and switches, connected together with miles of wiring and connectors, all hidden to keep them safe and your car beautiful. Your Porsche is much more electrically complicated than most of the vehicles NASA use to put people into outer space and your climate control has more computational power than Appolo 13!!!

Your engine has evolved to such a point that in complexity that a thousanths of an inch of wear in the wrong part, could cause what seem to be completely unrelated symptoms in another part, can cause vibrations, hesitation, loss of power, noises, poor fuel consumption or even complete destruction of the engine.

Now so far I have used two key words "Symptom" and "Cause". These are very different. Obviously when you bring your car to a garage it is the symptom which you want to go away. The symptom may be smoke from the exhaust, the smoke may be caused by a damaged component and we may find that damaged component very quickly, perhaps within an hour or two. We could just replace that component, which should make the symptom go away and the car seem as if it is fixed, but the same symptom may return, with the same or other part damaged again in very short order, because there was a cause of the damaged component which made the symptom that you witnessed, this could happen time and time again until someone bothers to go looking for the cause.

When JMG Diagnose a fault we fully understand the difference between causes and symtpoms, and as such we may tell you that we would like to perform a collection of tests. This is not our way of trying to make work for ourselves, instead it is our way of making sure we are not just being fooled into rectifying symptoms, which would cause your blood to boil if you only went a few miles and the problem came back.

Once our tests are complete, the technician will review all the results to see if a conclusive picture of cause and symptoms has formed, or if there are more tests which would make our diagnosis certain. Again, we are just trying to make sure that your money will not be wasted.

With some electrical faults, sometimes the diagnosis can be lengthy

When diagnosing an electrical fault, sometimes we will need to spend an unknown amount of time checking the cars wiring, sensors, control units and proceeding through both the Porsche factory and our own test plans. This can sometimes be lengthy, but we will always try to make sure it takes the minimum amount of time. So please believe us when we say we are unsure how long it will take to find a problem and we need authorisation to just go ahead and diagnose the problem and only charge for the time it takes to find the issue.

Sometimes you may search Google or Porsche forums for help with understanding the fault on your car. If you find some symptoms which are like yours, please beware that this is not a methodical diagnosis, if we do not perform a full diagnosis, we can not be held responsible for the fault not being rectified or for the fault coming back.

The good news is that JMG Invest heavily in diagnostic equipment to streamline the diagnostic proceedure, we have many items of equipment that Porsche main dealers and other specialists do not have at their disposal and our training is second to none, every technician is trained on Porsche cars to the highest level of qualification available over a five year apprenticship (where as most technicians are only trained to a basic level of competance) and of course we have three generations of Porsche technician's knowledge that has been handed down to every technician here.

Before I finish up, I would also like to bring your attention to something which would avoid your annoyance with having to pay a variable sum for diagnosis, the JMG Maintenance Plan. Under this plan you just pay a monthly fee for subscription to the plan, which covers the total cost every year of:-

  • One full service (parts and labour)
  • One interim service (Parts and labour)
  • One MOT test
  • One MOT
  • Unlimited labour for repairs
  • Unlimited labour for diagnosis

All you would pay for is any parts, consumables or any outsouced work (remanufacture or repair of a part rather than a new one). No complicated terms and conditions, no exclusions and no fuss. Whats more, never again will you worry about how much a repair might cost!


Read 4341 times Last modified on Tuesday, 19 March 2013 08:54

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