DDE and Cas3 repeatedly un-sync

chr15_123 · 06-21-2023, 09:43 AM

Afternoon all!

My 2008 BMW 320d e90 had a poor battery which I repeatedly jump started, stupid thing to do and I believe this caused an issue with the DDE and CAS-3. Any how I replaced the battery swapped the two modules from a donor car and car started lovely! After putting the panels back on underneath the bonnet and in the footwell I attempted to start the car to run it down and have new tires fitted only for the same problem to be happening again.

Key in, push start, lights on lights out, foot on the clutch push start and it turns and turns but won’t fire!

What could cause the modules to stop communicating or could it be another issue?

sdbmwcoding · 06-21-2023, 07:12 PM

Your car has CAS3. Dme and CAS synch by ISN, as long as they both match they’re synced. This is not like older cars which can unsynch and need a scan tool to resynch them. Firstly put your original dme and CAS back in, using a set from a donor car is going to cause way more issues than you previously had. Secondly, scan with ista. Your issue can be a multitude of different reasons, it may be possible the cultpit is the dme or CAS but it’s rare especially since your issue still persists with the donor set.

Scan codes and post them here with original DME and CAS installed

chr15_123 · 06-21-2023, 08:38 PM

Not sure this if this is meant as a question or statement but yes it has CAS3!

The reason I purchased the replacements from eBay simply were because I have two of these cars and after reading forums this seemed the next thing to eliminate. So initially I swapped them from my second car, lo and behold problem sorted - second car now wouldn’t t start. So I swapped the units back to their original cars and made the purchase.

When the eBay units arrived I fitted them in the problem car and again problem sorted at first.

As for ISTA, is there really a way of downloading the software and running it free? Or is it all just talk and time waste as I have attempted unsuccessfully!

sdbmwcoding · 06-21-2023, 09:33 PM

Yes there are many free installs out there. Bimmerscene and cartechnology are the go to’s for software downloads. (Admins if I’m going against rules posting external forums i apologies, please take my post down)

I’m sure there’s some on e90post but it’s a bit difficult finding software on this forum, the coding specific ones much easier to search through

Dontownane90 · 07-05-2024, 10:13 PM

Uh oh… I am finding myself in this same situation.

Had all keys lost situation and a local locksmith said he could help me. He connected his equipment and attempted to create a new key through OBD with no working key, no bueno. I now found the lost key, and again no bueno… the key is recognized by the car as the correct key but I get no ignition or no crank. Just power to some accessories and basic dash functions.

What has this done and how can I resolve it?

Will I need a new DDE, CAS, & keys?

It’s for a 2011 335d (diesel).

06-21-2023, 09:43 AM	#1
chr15_123 Registered 0 Rep 2 Posts Drives: BMW 320d e90 Join Date: Jun 2023 Location: West Sussex iTrader: (0)	DDE and Cas3 repeatedly un-sync Afternoon all! My 2008 BMW 320d e90 had a poor battery which I repeatedly jump started, stupid thing to do and I believe this caused an issue with the DDE and CAS-3. Any how I replaced the battery swapped the two modules from a donor car and car started lovely! After putting the panels back on underneath the bonnet and in the footwell I attempted to start the car to run it down and have new tires fitted only for the same problem to be happening again. Key in, push start, lights on lights out, foot on the clutch push start and it turns and turns but won’t fire! What could cause the modules to stop communicating or could it be another issue?
	Appreciate 0 Tweet Quote

06-21-2023, 07:12 PM	#2
sdbmwcoding Captain 194 Rep 802 Posts Drives: BMW M3 Join Date: May 2019 Location: San Diego iTrader: (0)	Your car has CAS3. Dme and CAS synch by ISN, as long as they both match they’re synced. This is not like older cars which can unsynch and need a scan tool to resynch them. Firstly put your original dme and CAS back in, using a set from a donor car is going to cause way more issues than you previously had. Secondly, scan with ista. Your issue can be a multitude of different reasons, it may be possible the cultpit is the dme or CAS but it’s rare especially since your issue still persists with the donor set. Scan codes and post them here with original DME and CAS installed
	Appreciate 0 Quote

06-21-2023, 08:38 PM	#3
chr15_123 Registered 0 Rep 2 Posts Drives: BMW 320d e90 Join Date: Jun 2023 Location: West Sussex iTrader: (0)	Not sure this if this is meant as a question or statement but yes it has CAS3! The reason I purchased the replacements from eBay simply were because I have two of these cars and after reading forums this seemed the next thing to eliminate. So initially I swapped them from my second car, lo and behold problem sorted - second car now wouldn’t t start. So I swapped the units back to their original cars and made the purchase. When the eBay units arrived I fitted them in the problem car and again problem sorted at first. As for ISTA, is there really a way of downloading the software and running it free? Or is it all just talk and time waste as I have attempted unsuccessfully!
	Appreciate 0 Quote

06-21-2023, 09:33 PM	#4
sdbmwcoding Captain 194 Rep 802 Posts Drives: BMW M3 Join Date: May 2019 Location: San Diego iTrader: (0)	Yes there are many free installs out there. Bimmerscene and cartechnology are the go to’s for software downloads. (Admins if I’m going against rules posting external forums i apologies, please take my post down) I’m sure there’s some on e90post but it’s a bit difficult finding software on this forum, the coding specific ones much easier to search through
	Appreciate 0 Quote

07-05-2024, 10:13 PM	#5
Dontownane90 New Member 0 Rep 6 Posts Drives: E46 2004 330ci (ISO E90 parts) Join Date: Sep 2019 Location: Ottawa iTrader: (0)	Uh oh… I am finding myself in this same situation. Had all keys lost situation and a local locksmith said he could help me. He connected his equipment and attempted to create a new key through OBD with no working key, no bueno. I now found the lost key, and again no bueno… the key is recognized by the car as the correct key but I get no ignition or no crank. Just power to some accessories and basic dash functions. What has this done and how can I resolve it? Will I need a new DDE, CAS, & keys? It’s for a 2011 335d (diesel).
	Appreciate 0 Quote