Key won't turn




Check the locks can open and close, the interior light is working with the door open, and the trunk opens remotely (driver-side door switch). If those fail to work, the main battery is dead.




Last edited by JCM_MB; Jun 9, 2023 at 10:47 AM.




Nice & easy: zero coding necessary.

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EIS module comes with different incarnations, complete with easily repairable Easter eggs.
> DIY vs. for profit:
Repairs involve time and skills with distinct priorities:
- DIY is ... "Do it once, do it right!"
- For profit is... "Please, come again soon"
> EIS Overall :
The Pro has no interest to go beyond fixing the main issue once he discovered the loose connector solders.
It's no-picnic to work under the dusty dashboard to extract the defective EIS... so personally, I want to overall each and every defects all at once.
A B C tags...
Tag A was the main issue with broken solder joints. Tech is fixing that with confidence repair will be complete! The connector should be epoxy glued! Solders are really not supposed to hold components onto the board.
👏
Tag B + Tag C: questionable connection pins - The video shows reliable pins that appear to be normally soldered. Some EIS models use unsoldered pins that develop CAN bus chaos with poor connections, high retransmit, limited bandwidth, data traffic-jams...
Take the whole module apart and diagnose what you see - If you can't, post circuit board pictures we'll help you pick out issues with regard to :
- electronic circuits
- mechanism lubrication
- cleaning contacts
Last edited by CaliBenzDriver; Jun 10, 2023 at 03:18 PM.

EIS module comes with different incarnations, complete with easily repairable Easter eggs.
> DIY vs. for profit:
Repairs involve time and skills with distinct priorities:
- DIY is ... "Do it once, do it right!"
- For profit is... "Please, come again soon"
> EIS Overall :
The Pro has no interest to go beyond fixing the main issue once he discovered the loose connector solders.
It's no-picnic to work under the dusty dashboard to extract the defective EIS... so personally, I want to overall each and every defects all at once.
A B C tags...
Tag A was the main issue with broken solder joints. Tech is fixing that with confidence repair will be complete! The connector should be epoxy glued! Solders are really not supposed to hold components onto the board.
👏
Tag B + Tag C: questionable connection pins - The video shows reliable pins that appear to be normally soldered. Some EIS models use unsoldered pins that develop CAN bus chaos with poor connections, high retransmit, limited bandwidth, data traffic-jams...
Take the whole module apart and diagnose what you see - If you can't, post circuit board pictures we'll help you pick out issues with regard to :
- electronic circuits
- mechanism lubrication
- cleaning contacts
ty very much




Once the key is inserted the EIS check the key, communicates with ECU, and ESL. When all agree, next.
Question: next can be either of
1- key is verified and the ESL activate electric motor and unlock steering column. If fails to unlock, prevents key from turning
2- allow turning of key, once key is turned to position 1, steering is unlocked.
i believe it is (1). Therefore, the little electric motor within the ESL can be damaged and if it fails to unlock, the key cannot be turned

Update
======
Here is a device, did not know exist. It can be used for diagnosis of the ESL, though I would not use it permanently.
https://abkeys.com/products/mercedes...w210-w639-3244
Last edited by JCM_MB; Jun 11, 2023 at 10:41 AM.




I don't know which way the handshake between EIS/ECU/ESL goes... use a scanner to see what is failing the security logic.
+++++ electric rack / ESL / EIS :
On vehicles with electric steering rack, the ESL is no longer located on column.
The stiff rack acts as a lock and as described in the video under post #17:
EIS key can turn unrestricted but power is not available: no dash, no crank, nothing happens.
Last edited by CaliBenzDriver; Jun 11, 2023 at 05:45 PM.




https://mbworld.org/forums/c-class-w...ml#post6935313
Last edited by JCM_MB; Jun 19, 2023 at 03:01 PM.


