WIS 80.57 Drive Authorization System: Difference between revisions

Revision as of 01:23, 8 June 2016

Tip for Using Mechanical Key

Turn it all the way to the left (CCW).

Weak Batteries in Remote Key Fob

The function may be affected by weak batteries in the key. If your key will not lock and unlock the car from 10 m (30ft) or more, your batteries are weak and that will compromise the strength of the IR beam. Try changing the batteries in the key before you go to more complicated (and expensive) efforts at restoring the function.

Batteries

2003 Update S500L Remote Key Fob has two batteries ie CR2025 x 2

2005 S500 Keyless Go Fob has only 1 Battery #2025

How To Change Batteries - Remote Key Fob

http://www.mbworld.org/forums/audio-...-pictures.html

Issue where Remote Control Key Will Not Rotate/Work/Turn in EIS (EZS)

Issue

Normally after inserting the correct Remote Control Key in the ignition lock (Electronic Ignition/Starter Switch (EIS) control module (N73)) it will turn instantly to position 1 (accessories), 2 (ignition on) and position 3 (engine start). However it seems that a common fault in the W220 occurs whereby the correct key will unlock the doors but once inserted in the ignition will not rotate and appears frozen. The vehicle cannot be started while the key will not turn.

Temporary Solution

The frozen key often happens intermittently causing huge frustration when out travelling. If you are lucky it may eventually start working again after continually trying and waiting twenty minutes. It is presumed that the EIS warms up slightly during this process.

Some owners have successfully used hair driers and electrical heaters to pre-warm the area around the ignition switch (EIS) to get the car started. Of course this is not a permanent fix but may get you out of immediate trouble.

The Failure

It is now apparent, thanks to several BenzWorld Members and especially YouTube Poster John Kennedy, that one of the microprocessor chips on the EIS becomes sensitive to cold temperatures. Warming this particular chip temporarily solves the problem until it cools down sufficiently again.

Of course it may be that it is not the actual chip that is sensitive to cold but one or more of the solder joints connecting the chip to the board may have developed hair line cracks which open when cold and close when warmed.

Investigation

The link shows one investigation with the bottom line that it was not a DIY solution. (Later note: YouTube Poster John Kennedy shows that a DIY fix is now possible.)

Parts of a W220 Remote Control Key
How the Remote Control Key Works in a W220
Diagnosing An Intermittent Key
Testing EIS Induction Power Generator Output
Test of Induced Voltages In Actual OEM Remote Control Key
Removing the EIS

http://www.benzworld.org/forums/w220-s-class/1300215-cold-weather-electronic-key-problems-5.html

Expensive Solution

The easiest but extremely expensive solution is to replace the EIS with a new one. It will cost over $3,000 and requires reprogramming of the new EIS to match the vehicle. As this is deemed a safety/security issue it can only be done by an authorized M-B agent.

DIY Solution No. 1 - Replacing EIS Microprocessors

With a huge acknowledgement to YouTube Poster John Kennedy (and BenzWorld Member pinkster, Dean, for discovering the video) whose excellent diagnosis shown in the video referenced below positively demonstrates a faulty microprocessor which caused his issue.

In his case the fault was due to the lower Hc08 microprocessor chip (4j74y), shown in the next figure.

This microchip was very sensitive to cold temperature, shown here being cooled with a can of freezer solution. Once cooled the key freezes in the lock and will not turn.

Warming the culprit chip, just with applied finger warmth for a few seconds, solves the issue and the key will turn again.

John Kennedy reports that the issue was fixed by replacing the faulty microprocessor.

Diagnosing W220 EIS by John Kennedy

Warning

Be aware that in other cases it may not be the microprocessor chip shown in this article that fails but could be other components or even the solder joints themselves so some diagnosis as per the video will be necessary to thoroughly isolate the faulty component or item.

Also be aware that working with electronic components requires some specialized skills such as fine soldering technique and appropriate earthing techniques to aid in prevention of electrostatic discharge. Surface mount electronic components can be very sensitive to excess heat and static electricity.

Replacement microprocessor chips are available but will require the original programme to be copied to the replacement chip which requires some speciallised equipment and knowledge.

Any comments on how the reprogramming is done would be appreciated, especially by some one who has successfully completed the DIY fix of an EIS.

Part Numbers - EIS Microprocessors

The part numbers for the microprocessors in the EIS from a 2003 (Update) W220 S500L are:

The 64-pin quad flat pack (QFP) microprocessor at the bottom location in the figures above has the following information on its face.
- 00198128A3
- EWM
- Motorola Logo
- SC510108CFU
- 4J74Y
- QQCF0305
- 06/03 R2

The 64-pin quad flat pack (QFP) microprocessor at the top location in the figures above has the following information on its face.
- 001981287A
- Motorola Logo
- SC510108CFU
- 4J74Y
- QQCV0309
- 20/03 R1

=Parts Availability - EIS Microprocessors

With thanks to BenzWorld Member pinkster, Dean these microprocessors are available for about US$30 posted from this source. [1]

DIY Solution No. 2

Australian BenzWorld Member iSteve reported that he purchased a replacement EIS with the same part number as his on eBay from the USA.

He was advised by his Indie that the US uses the same key frequency as Australia and hence the US sourced EIS would be compatible with the Australian standards.

Initially the Indie only "cloned" one EPROM which resulted in some errors such as;

A side marker lights error as Australian delivered cars do not have side marker lights.
The Steering Wheel Comfort feature would not work.
The odometer reading of the new unit was incorrect and unfortunately was higher than the original.

iSteve reported that his Indie used an In Circuit Serial Programming (ICSP) cloning tool and a laptop which allowed programming a microprocessor chip while it is still attached to the application circuit. That is there is no need for chip swapping.

The ICSP tool was used to save the original Hex files and copy them over to the replacement EPROMs. There were 88 differences between the old and the replacement unit.

After a second attempt whereby both "EPROMs were cloned" the new unit is working the same as the original but with no cold start problem.

Reference [2]

DIY Solution No. 3

MHH Auto senior member 'bawarek' has posted an excellent although very technical article titled, "The ultimate Mercedes EIS repair guide".

See http://mhhauto.com/Thread-The-ultimate-Mercedes-EIS-repair-guide

Everything you ever wanted to know about the Drive Authorisation System (DAS) and Keys

Information gathered from various official MBZ sources, included technical documentation, service documents, and even authorized technicians and factory personnel, by BenzWorld Member rudeney.

http://www.benzworld.org/forums/w163-m-class/1245088-everything-you-always-wanted-know-about.html

Programming W220 Remote Control Key

This video instruction is suitable for Car Key Master: CKM-100(PC Version) and CKM-200(Handhold Version), also it is suitable for Digimaster 3.

Part 1

Part 2