Diagnosing and fixing the aircon on a 2003 Honda Civic FINDING THE FAULT IS NICE BUT FINDING OUT HOW TO FIX THE FAULT IS EVEN BETTER ried and tested techniques provide comfort but in this article Brendan Steckler shows how more sophisticated tools and testing techniques can raise the game. This quest started with a customer calling to complain that his Honda’s aircon system was not performing well. Apparently it ran wonderfully when it was working but at other times it wouldn’t work at all, which puts it in a different category from the usual weak performance. Joe drives an immaculately maintained 2003 Honda Civic. It had an astonishing 400,000-plus km on the odometer, and the vehicle was still going strong. Joe was keen to keep the vehicle on the road and the aircon working properly, so I agreed to check it out. According to Joe, the aircon blows ice cold at times but at some point each day, it simply fails. A few hours later, it will be working again. This process seems to repeat itself each day. Imagine for a moment a list of 30 potential failures that could cause a specific symptom. Now imagine having to test every one of those components to prove their functionality. Obviously this would take a long time. Now, what can we ask the customer that could cut that list of 30 in half? What if we could then ask a subsequent question that could reduce that list of remaining potential failures by half again? How much more effective would our actual applied diagnostic time be? It all starts with having enough knowledge about the functionality of a particular system (and the components that make up that system) to create a bird’s-eye view or mental image of that system. If we have that in-depth knowledge, we can visualise what the symptoms may be if each key component was not functioning properly. All of this leads to effectively applied analyses and rapid, accurate diagnostics. Here are a few of the questions I asked Joe and his answers: Q: So the aircon does blow cold air at times? A: Yes, it blows cold every morning, at my lunch break, and every evening leaving work. Q: Does the blower stop at all? A: No, air always comes from the vent — it’s just warm air. Q: During the failure, do you get any warning lights? A: No, nothing unusual seems to occur — just the hot air blowing from the vents. Q: Are there any notable noises/squealing heard during the failure? A: No, the car seems to operate the same with no strange sounds. Q: Is there a specific time/place the symptom is exhibited? A: Yes, it always seems to fail after I stop for coffee in the morning.
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Auto Channel Issue #39 September 2021
A 2003 Honda Civic
Building a mental picture of the main components and their functions
A mental picture of Ohm’s law
