Last night my '01 F250, 5.4 4X4 was fine. This AM, upon starting it was not so good. My A/C is running warm, the ABS light is on and then the service light came on. My first thought is power, but I replaced the battery 2 weeks ago. I don't have a code reader, so I'll probably go by Auto Zone. Any ideas will be appreciated.

 

Check to make sure you belts are tight.

 

It has the one serpentine belt and that appears to be OK. Thanks.

 

Reset the computers.

 

hopefully the trouble codes will be informative.

 

I've been watching your posts over the past year or so, and this is NOT GOOD ADVICE.

The original poster should get the codes read FIRST. ESPECIALLY when it comes to the ABS. This is not something to play around with.

Every code is important in finding a solution to the problem, and if you clear the codes out you'll never know what the problem really was to begin with.

Get the codes read, at least the ones in the engine PCM and report back with what you find out.

 

Had trouble getting codes. The fuse, which is shared with the cig lighter, was blown. Then went through the fuses and found a 10A that controls the fan clutch, ABS and turn signals. Replaced and reset and back in business. I don't know why it blew but it's fixed. I have to get my own code reader.

 

Sure, read and log the codes.

But when so many unrelated codes come up all at once, it is more than likely a electronic glitch.

If it is a bona fide code --- like the ABS --- it will come up again immediately.

Resetting the computers will have no impact on safety nor your ability to read the codes when it turns up again.



The biggest problem I have seen on here, now that you mentioned it, is people panicking at the first sign of a code ---- and haul their ride to the dealer so the dealer can run up the meter on them.


Explain to me how you get a "code" that, upon reset of the computers, never turn up again ?

Codes do not necessarily indicate a problem with the item indicated by the code.









Oh... now that OP is back:



Pretty good --- when unrelated systems fail, it is likely to be something else.

In this case, common factor is power failure.

There is nothing wrong with the ABS.



Great work!


Now, if you took it to a hungry garage with an ABS code... you can be reasonably assured that they will be quickly assessing how much they can snow you... and if you look gullible... you would have bought yourself a host of ABS repairs to get the "light" turned out.

 

I found it strange that these systems would all fail at the same time. I assumed it was an electrical gremlin. I didn't realize that the ABS, A/C and turn signal would be on a single fuse. I went to auto zone to get the codes read and when that didn't work I started looking for a blown fuse that would power the computer reader. I had checked all the battery connections and charging system and vacuum. I always try the simplest things first, but was running out of options. If it wasn't a fuse I was thinking the computer itself. Fortunatly, it was a few fuses .

 

Key point: "when it turns up again". It may not until you're stuck somewhere on the side of the road. Resetting things for no reason, when the owner of the vehicle is not doing their own work, or doesn't have the scanners needed and has to bring it somewhere, is a NIGHTMARE for a mechanic. Not to mention the adaptive strategy in the PCM is gone and needs to be relearned, and emissions monitors are incomplete.

It can, and DOES introduce variables into a system that is heavily dependent on learned data, and doing it erases any important information that may be stored.

For example, my '97 Cougar's PCM stopped energizing the O2 sensor heaters. It complained about ONE. I checked it out, a few days later, it complained about another one. Few days later, it had cumulatively logged all four.

If I had followed your advice and reset the computer without knowing what was going on, and then brought it to a mechanic the next time the light came on, he would have changed one O2 sensor and thought it was fixed.

Instead, if I had NOT reset the PCM, the mechanic would have seen all four O2 sensors and immediately known (or found through the pinpoint tests from Ford) to check for O2 heater power, and on down the list until it said "replace PCM".

Another example: Do you power-off your desktop computer when it says "site unavailable"? Or do you try another web site to make sure your Internet connection is still up? Because this is basically what you are advocating. A general "all systems reset" is generally not the answer.

OK, enough of this


--

Back to the original poster, good for you that you found this - one fuse, huh? Sheesh...

 

Your example above is disingenuous and fundamentally misleading and false, as it concerns a fault that has as good a likelihood of being external to the PC as internal.

A relevant example is if your PC "hanged", that is,

- refused to respond to any keyboard / mouse input

- or cease to do anything

- or displayed the blue screen of death.



The code is in fact available and stored on the computer as it "crashes".

It is called a "memory dump" and is available to anyone qualified to examine.

It is also stored in volatile memory (states of the registers, etc.) and can be examined with equipment even if the PC is "frozen" as long as it is not powered off.

Memory dumps can be read sometimes, without equipment, by just rebooting the PC and reading the file.

I know of NO computer user except professionals in the industry or geek technicians who would, at that point, "READ THE CODE".

No, the would reboot, and see if the problem goes away first.


Insofar as your antique auto example --- that speaks to the weakness / problem / bug and trouble prone nature of on board diagnostics.

No competent technician equipped with the proper diagnostics software (e.g. Ford's own) would accept the DTC as the "end all" and go ahead and replace a part.

They would let the software cycle the system and see what it turned up.



I suggest we start a new thread in the Electrical / Electronics section to debate the merits of your allegations and my proven diagnostics procedures.

I dare say, when your PC crashes, you do not "freeze it" so you can read the codes (memory dump, and also what its register states are and what is in memory / what it was doing when it halted).

In fact, you routinely use my standard method when your computer crashes.


You turn it off. And back on.



I am just advocating using the same diagnostic procedure commonly used on every computer that crashes --- reset it and see if it happens again, before real time is spent on diagnostics.


Of course... I can give a great seminar on why it has to be done this way... given the limited number of lines of software code in the OBD module, and its inability to discern real from glitch failures, etc.....