300CE No Spark (Help)! 1990 DOHC 6cyl
 

Died in carport and now no start....
New coil, New CPS, New Cam Sensor, 12 volts to coil from EZL, distributor,wires and rotor 3 months old, good battery voltage, Starter turns engine fine, no spark output from coil and no 12 volt switching from EZL to coil ....good pulses from sensors to EZL viewed with O-scope..
Does anyone have any ideas.....?....or is this the dreaded EZL death ?

IF you have plenty of power & ground to the EZL & the crank sensor generates at least 0.5Vac while cranking...the EZL is the most likely problem.

Good luck

No Spark...
 

Thanks for the reply MB Doc....!
Was wondering what the minimum required signals are needed for the EZL to generate the switching pulse on the coil primary winding...?
EZL has about 8 inputs such as cps, cam, temp, vacuum and such...
I know the Crank position and cam position are needed for spark but not sure if it will fire if other signals missing or weak....Thanks again for your help....!

NO SPARK 300CE
 

Also trying to find good tutorial on pulling codes (types, tools,connectors, engine on or off) ?? ....not having much luck with info access....

EZL is super common on the CISE M104's. We have had two such cars in the last year, both had fragged EZL's. Went through the same diagnostics.. When there's nothing else left... When you Do get a new one be sure to renew the thermal paste!!

Jonathan

No Spark...
 

Thanks for the replies....Im just trying to find a way to read any stored codes to see what is going on since there has been a lot of work done on this vehicle ...seems to be two or more devices needed to read codes....

you can build one or buy one on ebay...

Cannot do anything but that's what most of us use.

Code availability 300CE
 

Yep...got one but have read that it can only read codes if engine is running.....
That is the problem....The engine has no spark and cannot run yet...I have the module apart to find the output stage if possible...you can de-RTV these with (rubber renew) liquid used on tape machine capstan rollers....

300CE Ignition module 104
 

Does anyone know of a list of Ignition modules that will work on this 1990 300CE M104..??
I see members speaking of some interchangeability between modules....where can I get that info if available.....Thanks.....this thing is killing me.....Help.....

Only cars w/ the M104's @ CIS, ie the early W124 coupes and the early R129 300's.

IIRC, 90-92 on the coupes, and 90-93 on the SL's.

Jonathan

Hi, these numbers were listed by mb doc,

0125452132
0125452032
0075457132
0075457032
0105453932
0105459632
0135458332
0105459532
016 545 0432

There was one on ebay last week for $350 buy it now.

ps.
I did hook up a ezl from a m103 to my twin cam just to eliminate the ezl being faulty.
Just three wires 2x to coil and one to ground, but you need the 4 pin loom with the m103 ezl.
It worked, obviously not a long term fix though.

EZL HELL Repair
 

I got the bad one apart without destroying it...
Sure enough there is a little 5mm square heat sink mounted resistive or inductive etched cicuit board that has 2 leads from the main board attached to it.....one of the bare wires was detached holding a broken off piece of the etched board....the other wire was attached to the 5mm etched demon....but the whole little board had become detached from the small heat sink....and there were dark spots on board like it had overheated somewhat....the little etched board measures about 7000 ohms lead to lead on another module out of the circuit....will try to remvove board from scrap module and install on the one I need......what a drag.....these are too delicate to live in an engine bay here in the south.....

Other than a reman unit from a MB dealer, a used one is the best bet.

EZL M104
 

Well this has now reached a point of sadness & desperation......depression has set in....

Does anyone have a pinout of an EZL # 016-545-0432...?????....
1990 300CE M104
This is the 8 pin per connector style....
Mainly looking for pins 2 and 5 on connectors XA and XB......HELP?!
Or any of the 8 pin per connector modules by chance....??

yellit, I know from personal experience that the EZL for a 1991 300CE cannot be reconditioned due to epoxy covering the internal components. Contact Beckmann Technologies if you want to confirm that fact.

After a futile search for a used EZL I ended up buying a new one from our local MB dealer for around $1,800 (wholesale price). If you go that route advise the Parts Department to search under EZL's for a 1990 300SL because their system will say the 300CE EZL is backordered (at least that was the case when I searched for one about 5 years ago).

Routine maintenance of the ignition system (distributor cap, distributor rotor, spark plugs and ignition wires) will prevent EZL failure. I know that's not what you wanted to hear, but those are the facts I learned from the same situation as yours.

EZL
 

Thanks for the reply.....This module is certainly of the devil.....

I have seen several posts about the inside epoxy thing, but what is in this one is just a very clear layer of very soft, almost flowable silicone gel or such....
It can be removed easily with q tips although it does want to pull back a bit.....
It could even be put back in after removal but it loses some of its transparency.....
Best consistency that comes to mind is that flowable silicon gel that you can get at parts stores for windshield leaks.......I am familiar with the epoxy bound circuits in devices but this is a different animal.....maybe its just in the Seimans units and not the Bosch.....Thanks again....

im no genious but have you checked the ignition control box on the drivers side firewall it controls spark output.just a shot in the dark.goodluck.marc

EZL....
 

Thanks for reply....Not sure what box you are speaking of ...??

ezl woes
 

yellit,

I believe the ignition control box on the driver's side firewall that mlozzi200478 is speaking of IS the EZL unit. As far as your problem goes, you can find good used EZL's on ebay or at your local salvage yard for very nice prices. I think that would save you a lot of trouble over trying to repair the one you have.

good luck & happy holidays

These guys have a couple for your car @ 150

http://www.lkqcorp.com/location/fSearch.asp?L=72

EZL
 

Thanks for the replies ...I know the unit is the EZL that is what I started thread with but thanks for trying to get me some relief.......I have it apart without destroying it....The only EZLs I found for 150 bucks are the M103 4 pins/per connector type...this unit has 8 pins per connector......no epoxy inside just a clear soft gel that can be removed.....I work on small electronic devices for a living (camcorders, 2 way commercial handheld radios,broadcast television equip and such) and this module is not too bad to get into ....Im just trying to identify a heat sink mounted smd chip that is a mystery...looks like a miniature strain gauge .....2 leads going back to main board....it is obviously overheated and cracked....The other modules have the same type component but all the modules at the salvage yard are gone......trying to find similar modules even if they are scrap.....so I can get donor components.....I always enjoiy trying to repair the impossible.....

Well, if you do end up figuring out how to repair these units, you might have a line of potential customers... ;)

EZL
 

Yep....Its usually just one component that has croaked in most devices....just wish I had an internal schematic to find the path that is down.....mostly power output stages ....this infernal thing uses lightweight semiconductors to switch off the coil current for field collapse......
So its probably in that output leg that does the on/off work.....
Not interested in the monetary side of these repairs...more just curiosity and resentment of being held hostage to a box.... ...this is a co-worker friend of mines Benz....and its just sitting there dead as a hammer.....he really liked the car up until this ....I usually hang out on the diesel forum....with my 240D and beater 300D.....This is my first post/thread on the gasser site...
Computer engine management is fine until it dies.....then your left holding an empty bag begging for info....before long, hammers and commode plungers will have usb ports and keyboards....and you will have to log in to to slosh the toilet.....damn......

yellit, best of luck attempting a DIY repair of the fried EZL. As I mentioned previously Beckmann Technologies which specializes in reconditioning electronic parts is unable to rebuild those EZL's. Be prepared for a long, frustrating ordeal.

EZL Ignition Module 300CE
 

Yep...Thanks Fred....
I spoke with Beckman and they said the owner of The shop may know more about them than the fellow I spoke with....may call after holidays and see what specifics makes them unrepairable....It is not epoxy filled and the components look very close to the other modules innards I have gotten into....mainly just curiosity on my part....
Thanks again for the replies....at least this DIY forum is available to view others efforts and history of the problem....

The only problem with this particular ezl is its scarcity.
Paying up to $900 for a second hand unit is not an ideal solution.
If mine were to burn out I would convert it to megasquirt to control the spark and probably convert to EFI or go Propane only.

EZL
 

Yep trying to think of aftermarket system that may work ok... Have not seen many posts on this topic with this model......Thanks...!

hi guys im just curious,what is an EZL? as far as i know all my plugs wires cap and rotor are original with 68k on them,the ignition system feels solid but you never know how much better it will run with a tune up,i had to regap the plugs and noticed a difference in acceleration and fuel economy,does it have something to do with the spark output control? sorry for my ignorance!

EZL is the German acronym for ignition control unit. It does indeed control ignition timing.