ECU replacement
#1
02-13-2021 | 09:02 AM
Thread Starter
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Junior Member
Joined: Feb 2021
Posts: 8
ECU replacement
Have a 2012 Focus SE hatchback that was having all sorts of electrical problems: random error messages, windows working/not working, random not going into gear, random not starting, etc. Once the car actually started, it ran fine. Checked for OBD error codes and only saw one mentioning a low value in an emission control, but nothing serious. Mechanic buddy suggested it was a failing ecu so I just bought one. Vendor says it will be re-flashed with the vin, but I will have to re-program keys by dealer or a locksmith.
Feeling a little over-my-head and looking for anything I might have missed, like a faulty ground connection or maybe some other failing component. Is it really this easy or is there something else I have to do? Any advice would be appreciated.
Feeling a little over-my-head and looking for anything I might have missed, like a faulty ground connection or maybe some other failing component. Is it really this easy or is there something else I have to do? Any advice would be appreciated.
#2
02-13-2021 | 10:29 AM
Senior Member
Joined: Jun 2010
Posts: 15,228
We call them Gremlins. How they get in the electrical/electronic system is often a mystery.
Sometimes we can get rid of them with what is referred to as a forced reset.When we do this reset, we will lose radio station memory, power seat memory, power mirror memory and some driving adaptive memory.So it is a good idea to copy the radio station settings . The others can be set as required. Adaptive memory gets reset as you drive and the system remembers how the vehicle is driven and shifting points.
A forced reset is done by removing the battery negative cable from the battery, and holding the removed cable end against the positive battery cable end which is still connected to the battery. After approx a minute or so the charges in the computer will go away and those gremlins hopefully go with them. The negative cable is then reconnected to the battery and the engine is started and the idle speed is allowed to set itself. The accelerator pedal must not be touched for at least a minute or so after starting the engine. Driving will usually allow adaptive memory to relearn your driving habits and shifting points.
Sometimes we can get rid of them with what is referred to as a forced reset.When we do this reset, we will lose radio station memory, power seat memory, power mirror memory and some driving adaptive memory.So it is a good idea to copy the radio station settings . The others can be set as required. Adaptive memory gets reset as you drive and the system remembers how the vehicle is driven and shifting points.
A forced reset is done by removing the battery negative cable from the battery, and holding the removed cable end against the positive battery cable end which is still connected to the battery. After approx a minute or so the charges in the computer will go away and those gremlins hopefully go with them. The negative cable is then reconnected to the battery and the engine is started and the idle speed is allowed to set itself. The accelerator pedal must not be touched for at least a minute or so after starting the engine. Driving will usually allow adaptive memory to relearn your driving habits and shifting points.
#3
02-13-2021 | 10:39 AM
Thread Starter
|
Junior Member
Joined: Feb 2021
Posts: 8
We call them Gremlins. How they get in the electrical/electronic system is often a mystery.
Sometimes we can get rid of them with what is referred to as a forced reset.When we do this reset, we will lose radio station memory, power seat memory, power mirror memory and some driving adaptive memory.So it is a good idea to copy the radio station settings . The others can be set as required. Adaptive memory gets reset as you drive and the system remembers how the vehicle is driven and shifting points.
A forced reset is done by removing the battery negative cable from the battery, and holding the removed cable end against the positive battery cable end which is still connected to the battery. After approx a minute or so the charges in the computer will go away and those gremlins hopefully go with them. The negative cable is then reconnected to the battery and the engine is started and the idle speed is allowed to set itself. The accelerator pedal must not be touched for at least a minute or so after starting the engine. Driving will usually allow adaptive memory to relearn your driving habits and shifting points.
Sometimes we can get rid of them with what is referred to as a forced reset.When we do this reset, we will lose radio station memory, power seat memory, power mirror memory and some driving adaptive memory.So it is a good idea to copy the radio station settings . The others can be set as required. Adaptive memory gets reset as you drive and the system remembers how the vehicle is driven and shifting points.
A forced reset is done by removing the battery negative cable from the battery, and holding the removed cable end against the positive battery cable end which is still connected to the battery. After approx a minute or so the charges in the computer will go away and those gremlins hopefully go with them. The negative cable is then reconnected to the battery and the engine is started and the idle speed is allowed to set itself. The accelerator pedal must not be touched for at least a minute or so after starting the engine. Driving will usually allow adaptive memory to relearn your driving habits and shifting points.
Not too concerned about radio and mirror settings, so if I go ahead and replace the ecu (since I already bought it), is re-programming the keys the only thing I need to do?
#4
02-13-2021 | 10:55 AM
Senior Member
Joined: Jun 2010
Posts: 15,228
If you had to provide your VIN to the seller,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,MAYBE !!!
If you were to change the PCM in your vehicle, it would need to be programmed with the info from the old PCM or "As Built" by the vehicle manufacturer.
This requires some special equipment and access to info only certain folks have. A certified locksmith, dealership or some one that has the knowledge, equipment and access to info can do the reprogramming of the replacement PCM. Sorry you already purchased the replacement, but here is what can happen and why I say , MAYBE.
If for ANY reason the programming is not 100% , Lots of things can happen , the worst of which is the vehicle will not recognize the replacement (Security System) and the vehicle will not start. So, you put the old PCM back in and now the system is confused and will not start with the old PCM either. This now will require the dealership or locksmith to come to your home and do the whole thing over again.
Suggest you verify this with your local dealership or Certified locksmith, It is only a phone call away.
If you were to change the PCM in your vehicle, it would need to be programmed with the info from the old PCM or "As Built" by the vehicle manufacturer.
This requires some special equipment and access to info only certain folks have. A certified locksmith, dealership or some one that has the knowledge, equipment and access to info can do the reprogramming of the replacement PCM. Sorry you already purchased the replacement, but here is what can happen and why I say , MAYBE.
If for ANY reason the programming is not 100% , Lots of things can happen , the worst of which is the vehicle will not recognize the replacement (Security System) and the vehicle will not start. So, you put the old PCM back in and now the system is confused and will not start with the old PCM either. This now will require the dealership or locksmith to come to your home and do the whole thing over again.
Suggest you verify this with your local dealership or Certified locksmith, It is only a phone call away.
Last edited by hanky; 02-13-2021 at 10:58 AM.
#5
02-13-2021 | 11:16 AM
Thread Starter
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Junior Member
Joined: Feb 2021
Posts: 8
If you had to provide your VIN to the seller,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,MAYBE !!!
If you were to change the PCM in your vehicle, it would need to be programmed with the info from the old PCM or "As Built" by the vehicle manufacturer.
This requires some special equipment and access to info only certain folks have. A certified locksmith, dealership or some one that has the knowledge, equipment and access to info can do the reprogramming of the replacement PCM. Sorry you already purchased the replacement, but here is what can happen and why I say , MAYBE.
If for ANY reason the programming is not 100% , Lots of things can happen , the worst of which is the vehicle will not recognize the replacement (Security System) and the vehicle will not start. So, you put the old PCM back in and now the system is confused and will not start with the old PCM either. This now will require the dealership or locksmith to come to your home and do the whole thing over again.
Suggest you verify this with your local dealership or Certified locksmith, It is only a phone call away.
If you were to change the PCM in your vehicle, it would need to be programmed with the info from the old PCM or "As Built" by the vehicle manufacturer.
This requires some special equipment and access to info only certain folks have. A certified locksmith, dealership or some one that has the knowledge, equipment and access to info can do the reprogramming of the replacement PCM. Sorry you already purchased the replacement, but here is what can happen and why I say , MAYBE.
If for ANY reason the programming is not 100% , Lots of things can happen , the worst of which is the vehicle will not recognize the replacement (Security System) and the vehicle will not start. So, you put the old PCM back in and now the system is confused and will not start with the old PCM either. This now will require the dealership or locksmith to come to your home and do the whole thing over again.
Suggest you verify this with your local dealership or Certified locksmith, It is only a phone call away.
So from what I think I understand, I have to cross my fingers and hope they did it 100% correctly.
Suppose I could call a locksmith, but they really won't know until we try, right?
Again, thank you for your time.
#7
02-13-2021 | 05:29 PM
Thread Starter
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Junior Member
Joined: Feb 2021
Posts: 8
They did require the VIN, and I emailed them to ask if they did an "as built" re-programming.
Tomorrow I plan to put the original one back in and do the forced re-set you mentioned to see if all the gremlins go away.
Seller said I have 30 days to send it back so gives me some time to do some driving tests.
Will report back if you are interested.
Thanks!
#8
02-14-2021 | 10:21 AM
Thread Starter
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Junior Member
Joined: Feb 2021
Posts: 8
In the meantime, I decided to put the original back in and try the forced re-set.
Now I get an "engine failure" error and no start.
What did I do??
#9
04-06-2021 | 08:22 AM
Junior Member
Joined: Feb 2021
Posts: 10
Have a 2012 Focus SE hatchback that was having all sorts of electrical problems: random error messages, windows working/not working, random not going into gear, random not starting, etc. Once the car actually started, it ran fine. Checked for OBD error codes and only saw one mentioning a low value in an emission control, but nothing serious. Mechanic buddy suggested it was a failing ecu so I just bought one. Vendor says it will be re-flashed with the vin, but I will have to re-program keys by dealer or a locksmith.
Feeling a little over-my-head and looking for anything I might have missed, like a faulty ground connection or maybe some other failing component. Is it really this easy or is there something else I have to do? Any advice would be appreciated.
Feeling a little over-my-head and looking for anything I might have missed, like a faulty ground connection or maybe some other failing component. Is it really this easy or is there something else I have to do? Any advice would be appreciated.
Might be better to have your original part repaired at https://www.upfix.com
Here is the service link
https://www.upfix.com/product-catego...rn/pcm-repair/
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