After replacing a failed lower radiator hose and filling the cooling system I wanted to make sure the electric radiator cooling fan was working properly.
The complaint was that sometimes after braking and then attempting to accelerate, it would not accelerate. I drove this around all morning and it did do that once and no more. After looking at scan data and memory codes recorded later and never again seeing the problem I parked it outside and was about to call the customer to update her. I happened to look outside at the car and the brake lights were on. I traced the brake light problem to the brake light relay being stuck on. I took the relay apart and the first 3 times I pressed it closed with my fingers, it stuck in closed position. After that, worked fine again. I replaced the relay and case closed because the car is drive by wire and because the relay was sometimes sticking on the ecm was trying to prevent engine run away and not allowing proper acceleration, due to thinking brake was on.
I have since learned that Nissan has a TSB concerning the problem and is deleting the relay all together,
Kenny@ggauto.repair
Not sure the date this was published in Counterman Magazine but probably in 2006.
Kenny@ggauto.repair
This was a very comprehensive and useful series. It is old now but I'd hate to see it lost and Motor magazine has a great archive. Let's use it.
You get some good tips and better understand the EVAP system.
Kenny@GGAuto.Repair
One of the most common falsehoods you'll hear concerning car repair is that trouble codes will tell you what is bad on your car. Just read the code and know what the problem is. There is no truth in that statement and, for some reason many people believe it anyway. I imagine it gets tossed out there most often by misleading ads from makers of code readers. I can tell you this, if a code reader would diagnose a car problem I wouldn't spend any time learning how systems work, how to test operation or definitely wouldn't spend so much money on testing equipment.
If you were driving a car and noticed a problem that you felt should be checked out, you would bring the car in and describe what you are noticing. Coming in and saying something is looking like a problem on my car, with no more information, then I'd have a really hard time determining what you are seeing that you are worried about. A warning light coming on in your car is the equivalent of that. The light is just saying hey I noticed something. If it stopped there I would have an extremely hard time determining the problem. If you said I noticed a problem with the engine sometimes being hard to start, idling rough and black smoke, then I would know what sort of things to start checking to determine the problem. Trouble codes are the way the car tells you more about what it is seeing that looks like a problem. It is giving you a place to start testing to determine the problem.
If I need more information from you about the problem, I ask for it. If I need more from the car computer, I use a scan tool to look a bit further. So, I ask for it.
Let's walk through one. 2012 Ford Edge Limited 3.5 Because the Malfunction Indicator Light is on and because that just means there is a problem, I need codes. I don't need codes to tell me what is wrong, because they don't. But I do need codes to know what sort of concerns the computer has noticed.
