What Your Dashboard Isn’t Telling You

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Televangelists promise to heeea-uhl you if you put your hand up against the TV – but that (usually) doesn’t work with your car. The “check engine” light won’t go out no matter how hard you holler for deliverance.

All you can do is pray you make it home.

Part of the problem is the absence of forewarning that is built into many modern cars. You’ve got more blinking lights and flat-screen displays than the bridge of the Battlestar Galactica – but often not much in the way of useful, real time info about the operating condition of your car’s engine and driveline.

The “check engine” or “service engine soon” light can mean anything from minor stuff you can put off for awhile (time to get an oil change or tune-up) to something potentially serious that requires right-now attention. As a general rule, if the warning light is yellow, you can wait. If it’s red, it’s probably more important – and immediate.

But more specific info would be nice, eh?

On the main dashboard display of most new cars, the automakers usually give you at least a coolant temperature gauge which – if you’re paying attention – will warn you of overheating before you actually boil over. But people often don’t pay attention – not noticing that the needle is creeping toward the red zone until it’s obvious there’s a problem. By which time, of course, it’s too late. A back-up light along with a warning buzzer to get the driver’s attention seems like it’d be a good idea, but not many (if any) cars have such a redundant warning system.

It’s usually either an idiot light that comes on when it’s already too late – or a gauge that’s just as useless if no one’s paying attention.

Why not combine the two – and have a gauge that’s idiot-proofed by an accompanying warning light and chime that prompts the driver to look at the thing and see what’s up? This is the layout in airplanes and it makes just as much sense to equip cars similarly.

And how about more gauges – especially useful ones such as a transmission temperature gauge , which could save motorists a fortune if they notice a running-hot unit before the unit cooks itself. Only a handful of new vehicles – most of them trucks – come with a transmission temperature gauge. It ought to be standard equipment on every car or truck with an automatic transmission. Especially vehicles that might be used to pull a trailer , etc.

Another bit of strangeness: Just about every new car and truck – including boozy highway cruisers driven by AARP snoozers – comes equipped with a large tachometer to keep track of engine RPMs, but the vast majority of new cars and trucks sold in the United States have automatic transmissions, rendering the tachometer a bauble of no particular practical use that eats up real estate on the dashboard – real estate that could probably be put to better use.

Even in cars with manual transmissions, tachs are almost superfluous – since all modern cars have electronic rev limiters to avoid the former potentially catastrophic mistake of over-speeding the engine.

Ford doesn’t even paint redlines on the tachs of its new cars anymore.

In an automatic-equipped car – especially a luxury sedan or family car with an automatic – a tachometer is as functionally relevant to the driver as a Mussolini-like Fez. Maybe it makes the driver feel sporty, but it doesn’t really do much for him.

A transmission temperature gauge, on the other hand, just might save him a wad of cash.

Throw it in the Woods?





  1. Info should already be readily downloadable via a USB interface or even Bluetooth. A diagram can be easily included in a PDF file, which most SmartPhones will readily process.
    So WHY, pray tell, isn’t this done? Well the answer is self-evident. Make vehicle on-board diagnostics easy to understand, and the dealer’s own service department, especially their “Service Writers” (the late Bea Arthur in “History of the World, Part I, had it pegged…”Oh! A BULLSHIT ARTIST! Did you bullshit last week? Did you try to bullshit last week?…”) couldn’t so easy engage in their daily flim-flammery. It might be easier to (1) understand how to keep the wee beasties alive longer, and (2) demand simpler, more easily maintained vehicles on the showroom floor.
    If you can’t dazzel with footwork, baffle with bullshit…and the clueless dumbfux in Detroit and in Washington wonder why the American Auto Industry, once the king, is now a toothless old lion and a laughingstock.

    • The OBD2 interface is mandated by the US federal government. The US government doesn’t allow for other options. However some makes do have the car dump info via cell phone interfaces.

      The story of OBD2 I heard is that the automakers wanted the car to communicate the code or be more detailed than the check engine light. The regulators in the government decided that if the car told people it was a minor fault that the owners would not bring the cars in for service. The result is that everything lights the check engine lamp (MIL).

      Blame the government, not the automakers. The automakers didn’t want their cars looking bad for minor things like a loose gas cap.

      Look around the web for the pdfs. Some manufacturers have published pdf’s that describe the logic behind various codes. I have them for my fords, found them on the motorcraft website. With a simple code reader and the pdf it works out pretty much as you’d like.

    • Hi Doug,

      For about $100 you can buy a code reader – a good one that will give you more than just the code (as the cheap ones do). This will let you – usually – pinpoint the problem pretty quickly, and also clear the code (so the light goes out) once the problem has been fixed. Owning a code reader is pretty much essential if you don’t like being at the mercy of the “service writer” (some of these guys actually work on commission, just like a salesman – which is just exactly what they are).

      I, too, prefer simpler stuff. If you’re handy, adjusting a carburetor, setting timing and so on is something that can usually be done in a few minutes with the most basic hand tools. And with a pre-computer car, diagnosing problems is usually much easier because there’s only so much that can go wrong. With a modern car, the problem can be much harder to isolate (one example, an intermittent fault with the electronics), as well as much more difficult (and expensive) to repair. Each – old vs. new – has its relative pros and cons.

      I’m not opposed to functionally useful modern technology – for instance, basic fuel injection and overdrive transmissions. But I do think we have already passed the event horizon of reasonableness, with regard to vehicle complexity and cost. It is absurd, for example, to fit twin sequential turbos to an economy-compact (Cruze) and I personally do not need or want 4-6 air bags, stability control or ABS – both of which add several layers of cost/complexity to any car.

  2. My aunt had a 1974 Chrysler Imperial LeBaron which had BOTH gauges and warning lights (the light was a tiny red LED on the gauge face) and a warning light that said “CHECK GAUGES” if anything was amiss. So the technology is there…but we won’t use it.

      • IIRC, that setup was available from 1969 on in Imperials…from 1969 to 1973, there were gauges and separate warning lights, and the Check Gauges light. In ’74, they went to little LEDs in the gauges to economize.

  3. The reason OBD2 has just a “check engine” light is due to our wise rulers. Our rulers decided that specific information about the car’s condition wouldn’t scare drivers into bringing their cars in for minor emission related faults. Thus serious faults and minor ones look the same on the dashboard.

    On this particular subject automakers went to bat for their customers. They wanted to have some sort of specific readout that would either give drivers a clue of what was wrong or produce a code that could be referenced in the owners manual. Our rulers said no.

    With OBD2 not only can there be all sorts of code info for when something goes wrong, an entire set of virtual gauges could be created on a screen. It’s nothing new, it’s how labview has worked for ages and how OBD2 software is often set up to display real time information. Like most brilliant ideas I think of, this one is already available on the aftermarket either communicating to the engine management system via OBD2 or using senders for old fashioned gauges.

    Factory gauges are dumbed down in part because of warranty costs. In particular ford switched the oil pressure gauge to binary indicator it is rumored because people kept bringing their cars in under warranty because oil pressure fluctuated normally.

    I do wish there was some kind of additional indicator for the oil pressure and coolant temp. I scan them but not very often while driving. Just a red LED in the gauge would do the trick.

  4. I suspect that there’s at least two reasons contributing to this. First, most people today don’t pay attention to any of the gauges anyway and have lost any sense of what the normal operating range should be for any given measure. In reality, the only ones that most people watch consistently are speedometer and fuel level. I suspect part of this is due to the overall improvement in mechanical reliability compared to cars of thirty years ago. It’s not a common concern for most drivers. The cars just work out of the box. It’s why a lot of people don’t know how to change tires, how often to change oil, etc. It’s good that cars are so improved but not good that we’ve become so isolated. It’s one more reason why I tend to recommend older cars to parents asking what they should get for junior who just got his or her drivers license. At least they’ll have to get familiar with the idea of a car as a machine that can break rather than a magical box that always responds on demand.

    Second, I have noticed that it is very much a style thing. My truck has a factory transmission cooler and can tow about 10,000 lbs yet does not have a trans temp gauge. The temp is monitored by the computer, and can be displayed on a device plugged into the ODB-II port, but it’s not built into the display on the dash. There’s no excuse for that. Similarly, none of the pitiful gauges I do have, except tach, give any indication of what normal range is or even provide actual numbers on most of them. None even have a red zone on them. However, they are all arranged symmetrically, similarly sized, and have nicely stylized scripts and designs to be pleasing to the eye.

    As cars get more complex, it gets harder to do things under the shadetree and it’s expected that they’ll be maintained by professional mechanics anyway. I guess they figure why bother showing anything to the owner, especially as most owners are not interested in knowing or paying attention anyway.


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