Random Thoughts... [Automotive Edition]

My Acura is at 140k miles and it's about to turn 14. No CELs ever.
Solution: buy a Corolla or a Civic.

Thanks for coming to my TED Talk.

To quote you right back at you:

Thanks for that useless contribution instead of just answering the question :rolleyes:

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I think you guys are confused by what Kat is saying, she isn’t saying she gets a ton of random CELs but rather that she got one for a working external temp sensor. Her contention is that something that minor and insignificant shouldn’t cause a scary CEL but have some sort of a less scary notification.

That depends on what the car is using the temp sensor for; I'm not entirely certain that it's all that minor or insignificant. I don't know if the Fail-at 500 does this, but I have seen several cars that use what you'd think are 'independent' exterior temp sensors (only feeding internal temperature displays) to run the climate control system and some even use them as a second/fallback sort of air temp sensor for the fuel injection system. If the latter case, that's fully justified in tripping the light. If the former, that's a bit marginal but understandable.

And the following yellow telltales:
  • Generic Warning Indicator Light

The fact that they thought it was necessary to add a generic warning indicator light on top of the myriad of specific ones and the CEL speaks volumes about how many problems they expected to have.

Also Google is your friend. About 15 more seconds of Googling, I was able to find the whole Fiat 500 repair manual. ALL 8558 PAGES OF THE DAMN THING IN ONE GIANT 101MB PDF. Yes, thats not a typo, the thing is eight thousand five hundred fifty eight pages long and freely available on the internet. It actually takes the record for longest repair manual I've ever seen, the previous record was somewhere around 2000ish pages. There are quite a bit of relevant mirror instructions starting on page 56, temp sensor info on page 529 and more mirror info on page 773, followed by dozens if not hundreds of pages of DTC troubleshooting procedures.

The XJ40's final full factory service manual including electrical troubleshooting and wiring diagrams is something like thirteen thousand pages IIRC. This is the 1991 edition - the final 1994 edition adds a couple volumes but those are hard to find:
s-l1600.jpg



My complaint was that FCA designed the mirror to be unfixable and expensive to replace, and if you are unwilling to buy a new one potentially give you a permanent check engine light.

Sans the check engine light issue - mirrors haven't generally been a serviceable part for decades, starting in the 70s. My fleet is a pretty good example; there aren't any service parts for the mirrors on my 87 XJ6, only the glass is replaceable on my 2000 4Runner, none of the motorcycles have serviceable parts in their mirrors, etc. I don't think I've had any cars with 'repairable' mirrors in the last... fifteen plus years? Your Fail-at is also really too small to have space in the nose for a more 'conventional' external temp sensor placement.

As for the CEL, it sounds like your cars are perfect candidates for this as a permanent install. I bought one to display temperature parameters (among other things), but you can use it to read CEL's underlying codes in real time and clear them as needed.




 
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and some even use them as a second/fallback sort of air temp sensor for the fuel injection system.
I was wondering if any cars do that, though it's rather strange why it would since MAF does that already.
mirrors haven't generally been a serviceable part for decades, starting in the 70s.
Yeah when I destroyed the plastic cover on the X's mirror the only thing I could do was order a whole new one. Did make the repair rather simple, some clips to take off door card, three screws and a plug for the electrical.
 
Re: serviceable mirrors: It's especially annoying when they are poorly designed...so the impala! In their infinite cheapness, GM decided to use the same mechanism for the power and non-power mirrors when designing the ones on my car.

This means they saved about three dollars a mirror, it also means that the mirror is a mass of extremely delicate cables (calling them wires would be a misnomer without electricity I think) that break if you so much as look them wrong, are impossible to fix, break during shipping for replacement, and because they are designed with veeery slow whirry electrical motors in mind the movement of the lever has little bearing on the motion of the mirror itself.
 
Ah if they use the sensor for other things i guess that is understandable for a CEL. I think the mirror would be less infuriating if they just made the sensor a seperate part the way the mirror itself seems to be sold as it's own seperate part so the cheesy unfixable plastic dying doesn't take thw expwnsive bit with it.

The beetle hasn't had a CEL in so long I worry somewhat it might be itself broken, but yeah the permanent scanner thing is probably a good idea for the fiat if Chrysler is gonna have so many ridiculous CEL triggers.
 
Regarding your prior comments, no one is attacking you or being aggressive. You've brought up some questions or complaints and I tried to provide insight as to why things may have been done as they were as someone who works in the industry. There was a conversation going, and thats about it.

Regarding your most recent comment about the sensor doing other things, it does. The ambient temp signal from the mirror is sent to the powertrain control module by way of the body control module. Your engine relies on the signal for a bunch of things, including fuel injection calculations, engine temperature parameter cross referencing, air conditioner compressor duty cycle, and a bunch of automated on-board self diagnostic routines.

I guess in theory dealers and warehouses could stock just the sensor, however the logic there is that if you already need to replace the sensor, chances are more likely than not that you've damaged the mirror and need to replace it too. By only selling the complete mirror assembly, they can cut down on complexity of part storage, and commonize the shipping methods from the 3rd party supplier that makes the part. This way they only need to send identical boxes out to either the factory or the repair part depot, and they don't need to worry about accidentally sending the wrong box to the wrong recipient (believe it or not, that already happens, so they're all about keeping complexity low).

I'm not going to continue discussing this topic here anymore.
 
Clearly this is the answer. Video is in Russian, but you don't need to know the language to understand whats going on.

 
In a surprise to no one, cheap brake pads suck
Those test are interesting because they show HOW MUCH.
The fact they suck shouldn't be a surprise.
 
Ah if they use the sensor for other things i guess that is understandable for a CEL. I think the mirror would be less infuriating if they just made the sensor a seperate part the way the mirror itself seems to be sold as it's own seperate part so the cheesy unfixable plastic dying doesn't take thw expwnsive bit with it.

Air temperature sensors are cheap. Thermistors of the appropriate type can be bought at retail for less than $20 sometimes as a ready-to-install part for a car; the volume price for a finished thermistor in housing may well be under $1. The custom molded plastic of the mirror housing will probably cost more than the sensor. The motor assembly that pans and tilts the mirror in power mirrors will almost certainly cost more.

Car manufacturers sometimes don't make the mirrors themselves anyway. They often have a supplier provide them to order and as such they are delivered to the manufacturer as a sealed unit ready for installation. In such cases, the manufacturer has to treat the entire mirror as a single part and therefore does not have the ability to provide parts even if they wanted to.

Should also be mentioned that a lot of these mirrors are actually put together using things like sonic welding and the like - if the mirror comes apart because you bashed it into something, you generally can't put it back together the way it was. In such a case, you're supposed to just replace the mirror anyway.

That said, most people usually don't bash their mirrors anywhere near as often or as badly as you report doing. This is partially why people don't have huge problems with the way things are and why the rest of us are rather looking askance at you.
 
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Right. I didn't watch the full video, but hopefully the guy mentioned that price doesn't ALWAYS correspond to quality. Cheaper pads from a reputable brand likely will be better than expensive pads from a sketchy brand. But for the most part the conclusion is accurate.
 
Clearly this is the answer. Video is in Russian, but you don't need to know the language to understand whats going on.


 
Right. I didn't watch the full video, but hopefully the guy mentioned that price doesn't ALWAYS correspond to quality. Cheaper pads from a reputable brand likely will be better than expensive pads from a sketchy brand. But for the most part the conclusion is accurate.

The data made that reasonably clear - for most metrics, the mid priced pads actually did quite a bit better than the top priced 'store' pads. I suspect those 'top' pads were Thermoquiets from the look of them and their lack of performance - a known issue with some applications in that line.

One thing that wasn't mentioned was that sometimes the OEM pads are garbage too. Pre-2000-ish USDM maker standard non-sport-vehicle pads were often pretty awful. The application can be important.
 
I suspect those 'top' pads were Thermoquiets from the look of them and their lack of performance - a known issue with some applications in that line.

While I've never had a car with Thermoquiets, I have multiple friends who have nothing but good things to say about them. From all anecdotal evidence I have regarding them, they seem like pretty good for the money. Though I wouldn't consider them 'top' tier by any means, I'd put them at the lower end of the mid tier.

Also regarding Thermoquiets, there are different variants out there compounds under the same brand name, so that's another factor to consider.

Pre-2000-ish USDM maker standard non-sport-vehicle pads were often pretty awful.

Not just Pre-2000ish. Even some modern pads are terrible because there are regulatory requirements that aftermarket pads sometimes don't have to meet. Like you said, its all about application.

I once met a guy at a local car show who had GT350 calipers, rotors and pads on his otherwise stock 2.3L Mustang because he though that since they were designed for a higher performance application, they were automatically safer for his daily commuter. That's just a clear case of stupid.
 
The front end looks like a tall Taurus to me.
 
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