Times when the manual didn't help

I know the standard advice is “Read the manual!” But what if the manual is no help? Has anyone ever been in that situation? I have. Here’s my story:
Before I bought my Corolla, I owned a 2000 Chevrolet Cavalier. This was the car that restored my faith in GM after two consecutive lemons, a 1984 Pontiac Sunbird and a 1993 Chevrolet Corsica. One evening after work I started the car and an amber indicator shaped like an open end wrench lit up on the dash. I shut the car off, got out, walked around the car, checked the tires, looked underneath for leaked fluids, dangling parts, etc. I opened the hood and checked everything I could think of. No luck. I got out the manual and it said something like, “This indicator will light when there is a mechanical problem.” (Sorry, I don’t have the car or the manual any more.) Wow. That was helpful. A “mechanical problem” could be dozens of things. Apparently something wrong but not serious enough for the “Check engine” light. After about a day I discovered I had a headlight out and that was the cause of the indicator. Anyone else?

Well, you learned what that light meant from the owners manual. That was useful information although only marginally so. A 2000 model cheap Chevy didn’t have nearly the diagnostic capability nor the driver display to tell you a whole lot more. Hang around this site a bit and you see posts that read like this - My Check Engine light came on or Service Engine Soon is flashing… what does that REALLY mean?

Or people who don’t know what any of those lights mean so they ignore them because they won’t open the owners manual. It is the most widely circulated book that NO one reads. There will be un-helpful things printed in all of them. Many of which end in the instruction to “See your dealer.” I would be surprised that statement wasn’t the very next line printed after;


Sure but I wasn’t aiming at people who don’t read the manual or who don’t know what “Low Tire” means. The first time the “Service required” indicator came on in my Corolla I immediately reached for the manual, only to find it was simply time for an oil change. This is for people who do read the manual and still can’t make head or tail of what it says.

I find it funny when the owner’s manual tells you to go to the dealer to have bulbs replaced . . .

not very helpful


OTOH, there are times when it’s necessary for some folks because of the way the car is made. The Mrs. had a 1997 Nissan Altima at one time and the left headlight burned out. On this car you had to remove the battery to get to the headlight but even then I couldn’t get it out. I took it to our regular shop and the owner of the shop couldn’t get the stupid bulb out of the socket. We had to leave the car so they could work on it. Somehow it doesn’t seem like that should be necessary.


I consider the owners manual and state drivers manual as a tie for least read. My 2010 Kia Forte manual listed rear driveshaft inspect and lubricate if necessary. It is FWD. When I asked about this at the dealership the service consultant knew it was a misprint concerning the AWD Sorento and was amazed that I was possibly 1 in 1,000 who actually read the owners manual.

The car’s computer diagnostic software was telling you it discovered a problem that needed attention, and was using the dash warning light to alert you of this fact. However it had no output device to tell you what the problem it discovered was. Your point is a valid complaint. Car manufacturers could easily include a small hand-held computer (you’d pay for it, in the price of the car) that would provide the owner a method to get the extra information to narrow down the nature of the problem. Manufacturers assume most owners don’t want to do this sort of debugging, and prefer to take the car to a shop who will have the hand-held computer (scanner) and the needed experience themselves. The manufacturers also probably prefer the owner doesn’t muck around with the computer diagnostic software b/c of liability and safety concerns. If they included the diagnostic tool with the car purcahse, then some owner might use it, not understand what the output data meant, and damage their car or themselves or others in the process, and then claim the manufacturer was at fault. Not including a method for the owner to determine what’s turning on that light is part of their risk management plan.

Not so much for my vehicles owner’s manuals. But for repair manuals, that’s an entirely different story. As one example, repair manuals apparently are written by several different authors. This causes the different sections of the repair manual to refer to the same part with 3 or 4 or more different names, which is definitely not helpful to the diy’er mechanic. Repair manuals will also refer to parts that don’t exist in your particular make/model/year, with no explanation.

I suspect most manufacturers would prefer that you take the car to a dealer for service no matter what the problem was simply on principle because that’s another way for dealers to make money. GM installed a generic indicator light as a catch all. I agree that most owners probably wouldn’t want to fool with a diagnostic computer but it was a bit disconcerting to be confronted with a “there’s something wrong somewhere” light. Maybe a few different indicators for various categories? It looks like it would have been a B1980 code, at least on some makes. I do chafe at the idea of not wanting me to change a headlight though.

My Corolla is OBD I. No warning lights at all when a headlight or any other light goes out. Somehow I get by … lol …

Interesting that the Daytime Running Light module monitors the headlights and can detect a lamp failure, this is from the owners manual;

"A flashing DRL telltale indicates a possible burned out
headlamp, or that the vehicle may need service to repair
a stuck DRL relay."

Both warning lights should have been on, perhaps it wasn’t noticed.

Lamp outage modules have nothing to do with Powertrain Control Module diagnostic protocol, Chrysler had lamp outage modules in the 1980’s.

IIRC the car had a DRL indicator but it wasn’t flashing or blinking. It would’ve been nice if it had been. I might’ve found the problem sooner. The only unusual light that was lit at that time was the “Service Vehicle” indicator.

The owners manual only covers general operation. You have to buy the factory service manual for diagnostic and repair information. Generally around $200. That’s what the mechanics use. So yeah, it’s in the book, but the big book, not the little book, and then ya need some tools too.