It's diagnostics Jim, but not as we know it

First Contact or the Final Frontier?

Published:  19 April, 2017

By James Dillon

The implication in this description is very interesting. The garage chain has described fault codes as being 'baffling'. I'm sure that they'll be double baffled if the vehicle presents with a running fault which doesn't set a fault code. I guess that this bafflement may be caused by reading 'baffling fault codes' and replacing the components or parts mentioned in the fault code, only to realise that this didn't fix the problem. I would have to suggest that you'd only be baffled at this if your skill levels were on the low side.

Any vehicle technician involved in diagnostics and worth his salt, knows that in most cases he is unlikely to be able to solve a vehicle problem using fault codes alone. For instance, we could cite hundreds of fault codes which have no direct components related to the setting of the fault code. Take the fault code P0300 'Combustion Failure Detected Indeterminate Cylinder' as an example. Exactly which parts should be replaced to stop this fault code from being set? It's only baffling if you don't have the required equipment, skills or knowledge to investigate the customer's symptom to establish the root cause.

One particular customer came to book a 'Dinostic'. How much do you charge for a 'Dinostic?' - Was his opening gambit. I asked why they thought they needed a diagnostic and the story unfolded that the customer paid £120 for three previous diagnostics to be done, all at different garages, all of which failed to uncover the root cause of the issue which concerned a rear door locking problem. I asked the customer what exactly the previous diagnostic consisted of. 'They plugged their computer in' was the answer. I suggested that the customer should probably buy a different service than before, and I explained that our method of investigating the problem involved several distinct elements over and above plugging in. Our investigation of their symptom would cost around the same as they'd already paid, but it would be much more comprehensive and would likely lead to the problem being discovered.  They were surprised that I didn't want to do a diagnostic, but they accepted that they had to try something different to get to the bottom of their fault. The invoices from the other garages showed that they had heard the request for diagnostics and reached for their scan tool. Three 'no fault found' printouts were in the vehicle.

How can a customer possibly know, without consultation with you, the expert, the best course of action? The next time you hear a request for diagnostics, probe the customer a little and you'll end up better meeting their needs and selling the right service.

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