Code P0605 - Transmission Issues

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SHOinVa

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Greeting All,
I know there are already a bunch of transmission threads but I did a search and could not find any threads on this specific code, and I thought it maybe helpful to someone down the road if I documented my problem.
- A few weeks ago I was heading home and she started acting up, at first I thought it was just a simple shudder under heavy acceleration but as time went on I experienced a few different symptoms which all seemed to be connected to the transmission. The only thing consistent about my problem was it only happened under moderate to heavy acceleration and after the car had been driven for awhile, when I first started driving, everything seemed fine.

I experienced the following issues
1. Heavy Shudder
2. Would not shift from 1-2-3, basically it bounced off the rev limiter for a few seconds, eventually it did shift or of I let off the gas
3. After I bounced it off the rev limiter really hard it got stuck in first gear, I had to restart it to get it to reset
4. It spun the front tires shifting from 1-2 that would be cool if it was supposed to do that but since it only happened once I think that was a mistake
5. At highway speeds I tried to pass a car and it was like it didn't know what gear it wanted, finally the motor revved a little and finally found the right gear and shifted
6. Lastly kind of the big one, I was on it hard, it made a sound I did not like and just stopped like I hit the brakes. After that it took awhile before it would move again like it was in the wrong gear, finally it started moving and I got home
- One other thing which may have a bearing, when I tried to removed the performance tune, the stock tune load kept failing. Finally it gave me a (Low Voltage or Battery) warning and basically said I needed to charge the battery to get it to work. For the record I have a really good battery that's only a year or so old.

I have a pretty decent understanding on how things work but I'm not that great at fixing them myself, so I kept it pretty simple
1. Checked the transmission fluid level (I have it drained and filled at least once a year and have the fluid tested)
2. Removed the performance tune (Brew City Boost)
* I would have done a data log and ask them to take a look at the numbers but they went out of business
3. After I removed the performance tune I drove it for awhile had some issues and checked for codes that's when I got the P0605 code

I was having this conversation in the Shudder thread and someone posted a link to a page explaining this code and it looks like its something to do with the ECM and ROM, it also says it could be caused by low voltage but basically it says don't drive and take it to the shop. Since there is really no one around here who knows anything about these cars other then the dealership, as much as I hate to do it I guess she's going to see her Uncle Henry on Monday. I'll try to figure out how to post the link on this thread ans keep you posted on what Ford says. I have no idea where this is going, I just hope I didn't hurt the trans while I was trying to figure it out.
V/r
Charlie
 

Bronco2fan

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That's a lot there. Here's a few questions.
When you went back to stock tune, you swapped the maf?
Have you tried disconnecting the battery for 15 minutes and have the transmission relearn? If not, I'd try that first.
Just a few things off the top of my head.
 

SHOdded

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could be a faulty tune, but we have had people brick their pcms before :(

as far as transmission goes, the "easiest" fix would be a faulty tss/oss or range sensor, or solenoid body assembly (tcm).

Gasoline Engines PCED
P0605 - Internal Control Module Read Only Memory (ROM) Error


Description:
The powertrain control module (PCM) ROM has been corrupted.​
Possible Causes:
  • An attempt was made to change the calibration
  • Module programming error
  • Aftermarket performance products
  • PCM
Diagnostic Aids:
Reprogram the vehicle identification (VID) block. Check for other DTCs or drive symptoms for further action. Make sure to check for aftermarket performance products before installing a new powertrain control module (PCM). If it is necessary to install a new PCM, refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) , Programming the (VID) Block for a Replacement PCM.​
Application
Key On Engine Off
Key On Engine Running
Continuous Memory
All​
Refer to the Description, Possible Causes and Diagnostic Aids for the DTC.​
 

SHOinVa

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When you went back to stock tune, you swapped the maf?
Yup I did, in fact I drove it to the store that day and had no issues and no codes, it wasn't until the next day when I had driven about 20 miles and tried to get on it hard that it messed up, when I got home that's when the PO605 code popped up.
Have you tried disconnecting the battery for 15 minutes and have the transmission relearn? If not, I'd try that first.
I could do that, but then I'd have to drive it around and I'm concerned that since it's making the transmission do things it really should NOT be doing if I keep driving it I might tear something up. I'd rather just take it to Ford and at least see what that have to say.

could be a faulty tune, but we have had people brick their pcms before :(

as far as transmission goes, the "easiest" fix would be a faulty tss/oss or range sensor, or solenoid body assembly (tcm).
Tunes been on it for several years with no issues, but just to be safe I installed the stock tune and I'm still having the same issues. You might be right but from what I have read its possible the transmission issues are related to the ECM issue. Anyway its going to Ford on Monday, its way above my head.
C/
 

SHOdded

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do you keep an obd adapter plugged in at all times? typically this will light up the dashboard if it is the culprit, just a stray thought.
 

SHOinVa

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do you keep an obd adapter plugged in at all times? typically this will light up the dashboard if it is the culprit, just a stray thought.
NO only when I'm checking for codes or loading tunes, at one time I worked out a whole wireless thing where I could look at the performance parameters on a small handheld tablet but I mostly just use the car for road trips and never really run her that hard so it ended up being more trouble then it was worth. I really think it may be some kind of voltage issue or the PCM is bad.

Either way she's off to see her Uncle Henry today and while I have little faith in any dealership I hoping the computer will give them a clear understanding of what's going on and it can be fixed, without selling a kidney or touring all the local repair shops. I'll keep you posted.
C/
 

SHOinVa

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Turning out about how I thought it would!!!!!!!!!

So I dropped her off on Monday at the dealership, I was heading out of town so I figured I'd just wait until they called me or I got home before I started asking questions. Needless to say I heard nothing from them all week. So I finally called today for an update. I was told it's a "PCM" issue, that its a discontinued part, and I could come pick the car up if I wanted to. I pointed out to him the transmission does not work correctly without the part, and after stuttering around for the right words for what seemed like minutes, I asked if he was telling me the car can't be fixed. LOL He said maybe they could look on eBay or something and would get back to me.

I'm not entirely sure it is a PCM issued, that code can also be caused by a voltage issue which could just be a lose wire (but lets set that aside for the moment) how is it that a central part to a car that's only eleven year old is not available through the company that built it. The upside is the PCM does not really cost that much and it looks like they actually are available on the aftermarket, so if it turns out he's right then good for me, if it turns out he's wrong it's not that bad. They really don't want you driving old cars do they, anyway that is today, I guess we will just have to see how this plays out, could be good, probably be a nightmare.

Anyone have any thoughts or input?
r/
Charlie
 

luigisho

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If you plan to keep thise vehicle for an extended time period I would have a hard to find essential part on a shelf or at least know that it will be still available in the future. For my old GenI and GenII SHOs I tried to keep a used good pcm, MAF, CCRM (relay module) and crank sensor on hand. This was over several years but I had them as a daily driver and couldn't afford extended downtime. There are some auto electrical shops in the area but I am not sure they would be able to pinpoint this. Which dealer did you use? Maybe discussion with another dealer service could illuminate whether they can probe and repair. You may need a PCM in the end.
 

SHOinVa

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If you plan to keep thise vehicle for an extended time period I would have a hard to find essential part on a shelf or at least know that it will be still available in the future. For my old GenI and GenII SHOs I tried to keep a used good pcm, MAF, CCRM (relay module) and crank sensor on hand. This was over several years but I had them as a daily driver and couldn't afford extended downtime. There are some auto electrical shops in the area but I am not sure they would be able to pinpoint this. Which dealer did you use? Maybe discussion with another dealer service could illuminate whether they can probe and repair. You may need a PCM in the end.
- I have a bunch of cars and its just me so usually there is no rush in getting them fixed BUT I do plan on keeping the car so that is actually a really good idea about stocking some extra parts.

- I'm going to make an educated guess and say after the mechanic completed the other things on the work list, pulled the code and found out they part was out of stock he parked the car and moved on to the next car on his repair list. Then they forgot to tell someone or they forgot to call me either way this is probably the first time in a few days anyone thought about fixing my car. I did a search and it looks like the part is available on the aftermarket so I'm going to give them a little more time and hope they can figure it out. At this point I'm just happy they even agreed to work on it, one day I'll tell you about how I was 3000 miles from home in my 89 F-150 and the Ford dealership refused to help me because the truck was too old to work on.
C/
 
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luigisho

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At this point I'm just happy they even agreed to work on it, one day I'll tell you about how I was 3000 miles from home in my 89 F-150 and the Ford dealership refused to help me because the truck was too old to work on.
C/
I wish this surprised me. I started doing my own work when I was young due to tight money. Now It's usually because of that same issue.

Are PCM's locked to a VIN or can they be reprogrammed to your VIN? Just wondering in case a used oem unit might be preferred.
 

SHOinVa

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I wish this surprised me. I started doing my own work when I was young due to tight money. Now It's usually because of that same issue.

Are PCM's locked to a VIN or can they be reprogrammed to your VIN? Just wondering in case a used oem unit might be preferred.
- If I could do it I would because when I do something I'm very meticulous, but the truth is while I have a pretty good understanding how things work I'm just not that good with my hands. I can do simple things but its easy for me to get over my skies and I have a hard time recovering.

- I don't have the answer other then they are available on line and they are asking for the vin number, I don't know if that's something they need or something they want.
C/
 

SHOinVa

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UPDATE - "Sort Of"

After 15 days at the Dealership they finally managed to find a replacement PCM, I'm not sure if they used one of the ones I found for them after I waited a week for them to find one on there own but since I know exactly what they cost the markup on the one they sold me is truly breathtaking. I would have said something when I was there but, I was in a bit of a hurry and didn't get a chance to look over the bill until I got home.

- It ran fine for about twenty minutes (like before it went in) but unfortunately just before I got to the house I felt just a slight glitch when it down shifted, so I did a couple of hard launches and the shudder at 1-2-3 is definitely back. If it proceeds as before it will gradually get worse, or maybe since they replaced the PCM the transmission is on a learning curve and will get better. I don't really believe that but sometimes hope is the only thing that lets me sleep at night. Either way it has not throw any codes yet so I'm going to drive it some and see which way it goes.

- I'm sure everyone knows this but I was told the 2010-2012 does not do store any retrievable data on its own, I know the PCM in the 2013+ is a lot different so maybe that does store some information. I'm assuming if it does get worse and has not been fixed, the dealership has a computer they can hookup and drive the car so they can see what it's actually doing.

Anyway that is where I'm at, as I predicted its turning into a real ordeal and I'm not sure how this ends, I guess it could still be a transmission issue but I have this bad feeling there missing something simple it will take them forever to find.

C/
 
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kryptto

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I was going to advise to drive normal for a bit and let it relearn. When my transmission was fully replaced the dealer reset the KAM and it was a bit rough at first... however sounds like it could still be a problem, let's hope for the positive.
 

SHOinVa

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Once Again - Sort of an Update

I have to find someone not a dealer to work on my SHO, I feel like the one I have been going too is mostly honest but I still feel like I've been taken to the cleaners and need a shower (that's not exactly how I would put it but this is a family friendly forum) every time they do work on my car.

- As stated above after they replaced the PCM it was running a lot better but was still having transmission issues, NOT nearly as bad but it was not exactly right. I did an internet deep dive and the symptoms indicated the possibility of dirty or low transmission fluid. I have done a drain and fill several times over years so I felt like the fluid should be reasonably clean but you never know. I had the dealership do a transmission flush just so I could cross that off the list of possible problems. Initially on the way home and for a day or two after it was still acting up but as I drove the car I felt like got better and the last few tines out I had no issues. Either way I have a long road trip coming up and for better or worse she's going as is. One way or the other I should know if its fixed when I get back.
- Thanks again for all the suggestions and help, hope everyone has a great Christmas and I'll post more when I know something.
C/
 

kryptto

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Once Again - Sort of an Update

I have to find someone not a dealer to work on my SHO, I feel like the one I have been going too is mostly honest but I still feel like I've been taken to the cleaners and need a shower (that's not exactly how I would put it but this is a family friendly forum) every time they do work on my car.

- As stated above after they replaced the PCM it was running a lot better but was still having transmission issues, NOT nearly as bad but it was not exactly right. I did an internet deep dive and the symptoms indicated the possibility of dirty or low transmission fluid. I have done a drain and fill several times over years so I felt like the fluid should be reasonably clean but you never know. I had the dealership do a transmission flush just so I could cross that off the list of possible problems. Initially on the way home and for a day or two after it was still acting up but as I drove the car I felt like got better and the last few tines out I had no issues. Either way I have a long road trip coming up and for better or worse she's going as is. One way or the other I should know if its fixed when I get back.
- Thanks again for all the suggestions and help, hope everyone has a great Christmas and I'll post more when I know something.
C/
Keep us looped I appreciate the updates, hopefully the trip goes well. Have a great Christmas!
 
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