An insight into how we diagnose vehicles and the cost

The complex electrical systems of today's vehicles,  together with modern petrol and diesel engine management,  make diagnosing and rectifying faults a specialist job .

Nearly all garages offer "Diagnostic Scanning " as a service but owning a fault code scanner does not make them experienced Auto Electricians. The diagnostic systems are needed to help with the process of rectifying faults and many people assume that once you plug into the vehicle,  everything will be right again.

One example is a mechanic's torque wrench.  This is a precision tool in the right hands,  used to obtain accurate torque to a bolt or other fastening BUT, in inexperienced hands,  it could break the bolt off causing unnecessary expense.

Diagnostic equipment in inexperienced hands can cause the same expense . Take this example:

You book in your vehicle with an airbag light on.  The garage scans car airbag system to find fault code for "driver's airbag".  They tell you the fault and that it needs a new airbag.

You pay a couple of hundred pounds for the airbag to be replaced and the light is still on.  Due to lack of knowledge in auto electrics,  the garage assumed because the scanner had the fault code present for driver`s airbag,  that this was the problem.

The actual fault was the horn slip ring behind the steering wheel,  which was less than half the cost and would have  rectified your problem.

We have a vast amount of Dealer Level Diagnostic Computers for all different  makes of vehicle,  enabling the reading of trouble codes, data logging, immobilizer programming and much more.  More importantly however,  we have highly experienced Main Dealer trained technicians using this equipment .

How do we charge for diagnostic work ?

Due to the nature of electrical faults,  the only fixed price we can quote is the initial diagnostic, which is currently £45.00 + VAT.     

If you take the airbag example again and imagine you called us for a quote to fix your airbag light staying on,  we would advise the initial diagnostic and up to an hour's labour to investigate the result of the diagnostic scan.  We would then call you with the quote to rectify the problem.  In this instance the pricing would have worked as follows:- 

To find find fault

Diagnostic                                                     £45.00

Labour to trace fault to horn ring                  £25.00

 To repair vehicle

Labour to replace parts                               £25.00

Parts approx                                              £75.00

                                                                ______

Total Repair                                              £170.00

As you can see,  the price to have the vehicle's fault accurately diagnosed and repaired was a lot less than the cost of just the wrong part  if the car was in the hands of someone with little knowledge of electrics .

Obviously not all faults can be found in just half an hour's labour,  in which case we would call you after the first hour if more time was required to investigate. You could then decide if you wished to continue or not.  By working this way, there is no hidden labour charge at the end of the job .