Technical 26 November 2026 ǁǁǁ͘ ĂŌĞƌŵĂƌŬĞƚŽŶůŝŶĞ͘ ŶĞƚ addressed, water will continue entering, and the fault is likely to return. The five whys isn’t about asking exactly five questions every time. It’s about continuing the investigation until the underlying cause is understood and supported by evidence. Look beyond the failed component Root cause analysis often requires looking beyond the system where the symptom appears. A failed alternator might be the result of oil contamination from a leaking engine seal. Repeated wiring failures could be caused by an incorrectly routed harness rubbing against a bracket. In both cases, replacing the failed component alone may only provide a temporary solution. This is where the evidence gathered during the earlier FIXDIT stages becomes particularly valuable. Vehicle history, previous repairs, environmental conditions and the results of the full function test may all help explain why the failure occurred. Sometimes the most important evidence isn’t found in the failed component itself, but in the conditions surrounding it. Don’t assume every failure has a hidden cause There is also an important balance to maintain. Not every component failure is the result of another fault. Components wear out, materials deteriorate, and electronic devices can fail internally. The objective isn’t to invent an elaborate explanation for every failure. It’s to establish whether the failure was caused by an external influence, normal deterioration, incorrect operation or another underlying problem. For example, a motor with worn brushes may simply have reached the end of its service life. However, a motor repeatedly failing shortly after replacement deserves a much deeper investigation. Good root cause analysis is evidenceled, not assumption-led. Learning from our own mistakes Sometimes the underlying cause can be traced back to a previous workshop repair. A connector left unsecured, a wiring harness routed incorrectly, or a missed calibration procedure can all create future problems. These situations aren’t always comfortable to investigate, but they provide valuable opportunities for improvement. If the root cause was an incorrect repair procedure, perhaps technical information wasn’t consulted. If contamination caused a failure, perhaps cleanliness procedures need reviewing. The objective shouldn’t be to assign blame. It should be to understand what happened and prevent it happening again. A workshop that learns from its failures becomes more efficient, more consistent and ultimately more profitable. Diagnostic insight When you identify a failed component, ask yourself: “Is this component the cause of the problem, or is it another symptom?” That question can be the difference between a successful first-time repair and a vehicle returning with exactly the same complaint. FIXDIT Takeaway Don’t just identify what failed. Understand why it failed. By the end of the Determine the Cause stage, you should understand the failure mechanism and have enough evidence to decide what needs repairing, replacing or correcting. In the next article, we’ll explore the ‘Implement repair ’ stage, where we turn that understanding into a professional, reliable repair. Because diagnosing the fault correctly is only part of the job. Making sure it doesn’t return is what completes the solution. tinyurl.com/FIXDIT
RkJQdWJsaXNoZXIy MjQ0NzM=