Z3 EWS Communication Issue (AK90 flash)

[TC4]

This is the first time in a very long time I have been stumped with an electronic issue on one of my cars.

I recently changed the ZCS on my EWS module and once I wrote the new ZCS with NCSExpert I lost communication with the EWS module and could not connect to it whatsoever.

I made a copy of the MCU with AK90 before writing the MCU flash from when I first bought the car.

Still could not connect to the EWS no matter what I tried. INPA, DIS, Tool32, etc.

I decided to write the MCU flash I backed up that had the new ZCS. Not sure what happened, but was able to communicate with EWS with INPA, DIS and Tool32. Was able to start it once. After turning the ignition off I lost communication again and have not been able to connect to the EWS module since. I have flashed the MCU with AK90 back and forth between the two dumps I have and it is not working. No fuses are blown. Everything else seems to be working properly.

Currently have an error in DME "EWS/DWA...". All software reports no response from the control unit.

Any ideas?

[flyfishvt]

When you used the AK90 what did you use to clean off the resin off the EWS circuit board? Just taking a guess here but I'm thinking you damaged the EWS board.

[TC4]

I carefully scraped it off with the edge of a knife. I don't think this caused an issue as I did that two years ago and have driven the car since then. When I took the module out the other day I didn't have to clean the pins.

[TC4]

Any thoughts? I'm thinking about buying a used EWS2 unit and reflashing it to see if that works.

No communication with mine whatsoever. No idea what the issue is.

[TC4]

Anyone else ever had a similar issue?

[328 Power 04]

I would clone your old ews into a used one. Sounds like you had a hardware failure after coding, which is weird in itself.

[Fx323i]

Which ews module and DME do you have? I have a few ideas. Send me a PM, I will give you my e-mail to send me the original file read by AK90. I will try to help.

[TC4]

Sent you a PM. I am currently waiting on a used EWS2 unit I purchased on eBay.

[TC4]

I fixed my issue. Long story short fuse 31 was blown which is for the EWS.

I had overlooked it several times, but after pulling it today I could see a small break in the filament.

After replacing the fuseI was able to connect to my EWS. Still couldn't start the car so after following Fx323i's recommendation of unchecking the used keys in the EWS Editor and flashing the .bin back I was able to start the car after the keys resynchronized.

[purplecty]

I fixed my issue. Long story short fuse 31 was blown which is for the EWS.

I had overlooked it several times, but after pulling it today I could see a small break in the filament.

After replacing the fuseI was able to connect to my EWS. Still couldn't start the car so after following Fx323i's recommendation of unchecking the used keys in the EWS Editor and flashing the .bin back I was able to start the car after the keys resynchronized.

Did this require re-writing the ews data back to the keys as well or they automatically pulled in the current stored rolling code after each keys first use?

Sent from my SM-N960U using Tapatalk

[TC4]

The chips in the keys can't be reprogrammed as they are write once only.

The key passwords are stored in the EWS from new. Unchecking the used box and reflashing the EWS forces the keys to resynchronize with the EWS module.

[Fx323i]

It works the opposite way. When you reset the keys random codes in ews, if everything else is verified, the ews stores the key's random code and then works with it as usually.

[328 Power 04]

It should not be an issue if you have a straight clone, without any successful engine run on it.. right?

I have cloned plenty of EWS3, but I was under the impression that ews2 didn't have key rolling codes.

[Fx323i]

On ews2, key-ews system is the same with ews3. The dme/dde-ews system is different. Also, some ews3 and ews4.3 work in ews2 mode.

[purplecty]

It works the opposite way. When you reset the keys random codes in ews, if everything else is verified, the ews stores the key's random code and then works with it as usually.

Are you saying unchecking the key as a used key in the ews and re-writing it back to the ews will reset the key code for that key, which should allow that key to start the car? I have had a few rolling code key errors, where re-writing the EWS data to the Original EML style key(in its current key slot)allowed the car to start this way. Im trying to make sure I follow the correct procedure from you more experienced EWS guys...

Sent from my SM-N960U using Tapatalk

[purplecty]

The chips in the keys can't be reprogrammed as they are write once only.

The key passwords are stored in the EWS from new. Unchecking the used box and reflashing the EWS forces the keys to resynchronize with the EWS module.

Do they write to the next unused key slot if its a new virginized transponder?

Sent from my SM-N960U using Tapatalk

[Fx323i]

Purplecty: Your rewriting of keys should work too if the key belongs to the ews. I rather repair the data in the ews because many people are shipping the units to me for a repair so I do not need them to ship the keys, too (matter of trust of the customers in me and also our very poor postal service here). Nevertheless, in the ews you can check if the data written are correct. With the key you must trust the Write key OK tab. I also would recommend to rewrite the key with the data for the same position in the ews.

Regarding writing to new unused transponders, it all depends on how many slots have been used. I personally never use the next slot because if anyone in the future would order the next key from BMW, it would have been on the same position. So I rather go from the other end if there is enough space, or use the position of knowingly lost key.