OBD does not communicate with safety inspection computer


olliek
03-19-2009, 06:20 PM
Hi - I am new to this - and unfortunately an idiot when it comes to cars. Our 2000 Windstar was at the safety inspection today and the guy told my wife that the car didn't communicate with the computer. Apparently he check all the fuses.
It was at the garage this morning to get some part exchanged, something to do with the steering, but the part was at the front wheel. I remember hearing someone say that the computer has to reset once a part gets exchange and you have to drive 70 - 100 miles before you can get the stickker successfully, but then I thought (the part looked like 3 point star) this couldn't impact the ODB?

Any ideas what it could be? Also the MA vehicle safety website says ". Does your vehicle’s OBD system communicate with the analyzer? If your vehicle’s OBD system cannot communicate with the station’s analyzer, the OBD system must be repaired before the emissions test can be completed." So any idea what the worst case scenario cost would be

Notes: no check engine light or anything came on and it did connect to the safety/ emissions inspections computer with no problem a year ago.

Thanks for your help

wiswind
03-19-2009, 10:08 PM
What I would do is head over to the local AutoZone or Advance Auto Parts......etc.
Most of these places will read your OBDII codes for FREE.
This will tell you if your OBDII port is functioning at all.

12Ounce
03-19-2009, 10:54 PM
At your left foot, you will find a fuse/relay panel .... replace fuse #17. Your cigar lighter will also start working ... until you overload it again!

olliek
03-20-2009, 09:20 AM
At your left foot, you will find a fuse/relay panel .... replace fuse #17. Your cigar lighter will also start working ... until you overload it again!

Thanks guys, the cigarette lighter is working and he checked the fuses. Also I went to the garage this morning and he showed me on his obd reader. It was all scrambled, he checked another windstar and his reader worked fine.

any other suggestions, please? Thanks for your help. Windstar LX 2000.

olliek
03-20-2009, 02:43 PM
OK, I went to justanswer.com, clearly not the most satisfying exercise, but I got some hints.

So if it is not the wires, it could be the PCM, powertrain control module, i looked and that should be around $130.

what i fail to understand - and now you can call me an idiot again - what has the PCM to do with emission?

Any help appreciated, I am just trying to get clever here.

12Ounce
03-20-2009, 04:43 PM
The PCM is THE controller for the engine and transmission ... so it is all important to emissions control and engine performance.

But there is a far greater chance that there is a broken or grounded wire somewhere in the maze of harnesses involved ... than there is a problem with the PCM. I have repaired many wires on my Windstar, but still running on original PCM after 260k miles. The data link connector is a 16 pin device with 7 active conductors attached. It is connected to the PCM on 3 PCM terminals. I would suggest you buy a Ford wiring diagram for your model and to a pin-to-pin check on the related harnesses. Better than throwing money at who knows what.

garync1
03-20-2009, 08:21 PM
Ok if you checked the fuses and relays.. Think back to if you ever jumped started a car that was hard to start or had a hard time being jump started or had some type of short circuit that you remembered. The reason I ask is sometimes it not at all hard to short the PCM out. Really its a lot easier than you think.. Now if you end up having to buy a blank OEM PCM you will need to get it flashed programed. Its usually around 70 bucks maybe a little more depends on where you live.. Now.. The problem is you may want to call the dealer and ask how much and if they still have the flash program for the 2000 model.. If you end up getting a new blank PCM get it from a dealer web site. Don't get a remain unit. Had a bad deal with them.. Your van will run on limp mode.. In other words it will run fine but some interior accessories may not work until the flash program is installed.. Long explanation on why this is.. But I have put a few in..

wiswind
03-21-2009, 10:48 AM
The PCM is kind of 2 modules in one.
First, it is the computer that controls the operation of your motor and transmission.
It controls how much fuel to spray through the fuel injectors to maintain the correct air/fuel ratio for optimum operation.....and it controls exactly when to spray out of which fuel injector.
It controls when to apply the spark to each spark plug.
It controls the idle speed when your foot is not on the accellerator.
It monitors a LOT of sensors to make the determination of what to do when......the input from the oxygen sensors help the computer to determine if the air fuel ratio is correct.....and how much to adjust it.
So.....no PCM......no operation of the motor.
Now.....over time, they have built in a lot of fail safe protection.......if a sensor goes bad......the PCM will be able to sense this.....and ignore that sensor.....going into a kind of "limp" mode.

The 2nd part of the module is the part that actually drives the devices....taking the computer signals and powering the various devices (fuel injectors, coil pack, etc).

Starting in 1996, the government required that ALL vehicles sold in the USA, regardless of where built or by who......use a basic set of "Generic" codes.......so that a given set of data can be looked at with the same piece of diagnostic equipment (like a generic code reader) and a set list of parameters can be read from andy 1996 or newer vehicle......the same codes......same wires in the connector doing the same thing.

As the newer vehicles have computers that monitor so many things......for example, the FORD Windstar has 4 oxygen sensors......monitored by the PCM......why would we need to stick another oxygen sensor up the tail pipe to measure what is already being measured?.
For this reason, most emission testing that states now use simply involve looking under the car to see if things that are supposed to be there are, indeed there (like the catalytic converter) and that the fuel cap holds pressure......and then connect to the PCM using the connector that is below the steering column to make sure that all the monitored systems are in good order.

My suggestion of having another place try to read the codes was to eliminate the unlikely possiblility that there was some unique problem with the test setup (or operator) at the first place.......saving you further problem.
As it seems that the problem persists after further investigation.......then it will be necessary to have someone troubleshoot the problem.
As mentioned......loose/broken wires, connectors or a defective PCM is possible.

olliek
03-21-2009, 12:47 PM
The PCM is kind of 2 modules in one.
First, it is the computer that controls the operation of your motor and transmission.
It controls how much fuel to spray through the fuel injectors to maintain the correct air/fuel ratio for optimum operation.....and it controls exactly when to spray out of which fuel injector.
It controls when to apply the spark to each spark plug.
It controls the idle speed when your foot is not on the accellerator.
It monitors a LOT of sensors to make the determination of what to do when......the input from the oxygen sensors help the computer to determine if the air fuel ratio is correct.....and how much to adjust it.
So.....no PCM......no operation of the motor.
Now.....over time, they have built in a lot of fail safe protection.......if a sensor goes bad......the PCM will be able to sense this.....and ignore that sensor.....going into a kind of "limp" mode.
.

Wow thanks that was comprehensive. Thanks a lot. So if I try a bit of backwards logic. If the PCM was gone, then I wouldn't be able to drive? So that should rule out a complete failure.

So that leaves two possibilities, one of the wires broke or grounded and/or sensor going bad?

And if this is the case then replacing the PCM doesn't do a think, cause you still have a broken wire or bad sensor. By the way, I had it checked by two garages just in case and by handheld reader, all the same, no connections or readings.

Which reminds me - a while ago I lost my cruise control. Could that be related?

I am starting to like this, not that the fact that somethings wrong, but I need to get back into fixing and understanding things myself.

Additional question, my windstar 2000 3.8 has 82,000 miles, I was contemplating getting an extended warranty, any word of advice on that?

12Ounce
03-21-2009, 02:17 PM
So that leaves two possibilities, one of the wires broke or grounded and/or sensor going bad?
I would say "no" to sensor failure at this time.


Which reminds me - a while ago I lost my cruise control. Could that be related?
Oh yes, it is also fed by fuse #17! Are you sure all front cigar lighters are working? Maybe there is something "iffy" about this 12 volt wiring. Maybe a "make/break" connection somewhere.



I would change out the fuse (myself) just to be sure.

olliek
03-21-2009, 04:37 PM
Thanks, will do. Thinking out loud here. So the cruise control went bad but it didn't go immediately bonkers. I went came back again, then went again, and so on, until it went completely. wouldn't that then indicate more of a wire problem??

Thanks again, you guys are fantastic1

garync1
03-21-2009, 07:07 PM
Yes I would check out all things first before replacing a PCM... But if one part of the PCM goes bad then it would have to be replaced.. But most of the time a car will run even if the PCM is bad... Just depends on what part of the board went bad.. I know on the older Nissan 300 zx .. It will run really rough.. On a 2005 Dodge minivan everything ran fine Just the CEL came on.. That is one reason why I do not like to Jump start cars with my van.. Unless I am doing it. Only takes one opps to mess things up..

wiswind
03-21-2009, 08:01 PM
It is possible for just one line on the PCM to be bad.....however, it is best to see if there is something else causing the failure.....so you don't spend the money on a expensive replacement that is not needed.....and does not solve the problem.
A wiring diagram will let one know what pin on the OBDII connector goes where.....and it can then be followed, using the wire color and pin-out locations for various connectors.

Now....cruise control.... A VERY common cause of this is a leaking brake pressure switch.
This switch is located on the bottom of the brake master cylinder.....brake fluid leaks into/through the switch....causing problems just a you describe.
The solution is to replace with a new switch, which comes with a adaptor wiring harness that matches the connector on the new switch up with the connector on the wiring harness.
This is a simple repair that you can do yourself......after buying the "kit" from the dealer.
I have pictures posted in the pictures that the link in my signature takes you to.....that show the brake pressure switch replacement process.......which, though on my '96, will be applicable to your 2000 model year (though many other things in my pictures will be different).

Extended waranties are usually not worth it.
There are a LOT of companies that are trying to sell you extended waranties for your vehicle.....I STILL keep getting notices in the mail telling me that my factory waranty is about to expire......to act NOW to continue my coverage.
My vehicle is a 1996 with over 208,000 miles on it.......so the factory waranty is long gone.....forgotten.....history.....so it is certainly not FORD Motor Company that is sending me this stuff.......and you want to be certain of WHO is providing the coverage....and what hoops you have to jump through to get a repair covered.
They certainly will be nice about taking your money.....but will they be nice when you expect them to pay out?
One has to carefully read ALL the fine print......and see what is covered.....and what is not.....and what the process is to get the repair covered.

I think that the most important thing to have is a local shop that you can TRUST to be honest and competent in servicing your vehicle.
That....along with keeping super on top of routine maintenance will help you get the most out of your vehicle.

1339tony
08-21-2013, 06:21 AM
OBD does not communicate with safety inspection computer,
for your case, i think it is because the obd2 you use didnt been updated or the obd2 scanner is not support your car. may be you need to get a new one. i suggest you this shop, not bad really.http://www.kobd2.jp. or any questions about your repairing,you can also chat with their technicial online live support.

northern piper
08-21-2013, 08:23 AM
The other thing I'd be doing is inspecting the wires where they leave the back side of the odb2 connector under the dash. My experience with wire shorts/problems is where a where goes through or around some structure the chafe can easily happen. This might be as simple as a bad wire at the back of the connector which is shorting to another. Take a flashlight and carefully look at the wires that lead from the connector. I'd be ruling out the simple things before replacing a computer for sure.

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