Mercedes W169 EZS intermittent no start problem

[armpower]

Hallo

I have a intermittent problem on a MB W169 180Cdi, sometimes (maybe when the car is cold) the starter not work.
It's not a starter .I've checked.
When this problem appear the communication in Engine Ecu is not possible and you cant' heard fuel pump.
The relays are ok, and when all is ok are energized correctly by the engine Ecu (Fuel Pump, starter and +87) after rotating the key in EZS.
When the car not start , on ABS-ESP and Electric steering rack ecu are memorized several dtc.
When this symptoms appear, all car's ecu are diagnosticable only engine ecu is not present or recognized.
ESP dtc 5425 communication with engine ecu or ezs module not possible.
ES dtc 5521 one or more messages from engine ecu are not present on Can bus.
No error in EZS.
I think there is a communication failure from EZS to engine Ecu.I've checked heart point and + lines .All ok.
I'm focused on EZS internal problem.
Because when the car not start, if you re-insert o rotate the key two times, all start working correctly.
Authorization, first key is ok.
When I insert the spare key on dash display a message appear.Key tech-in in progress.And nothing happens.Spare key not
work , not turn the ezs , remote not work.

Before changing EZS i need some info or tips from experienced users.
My EZS is 1695451908 (mask 1L59W ).I have some used EZS but with other number 1695451508 ( 3L40K)and 1699051500 (1L59W).
But i don't think i can transfer the EZS dump to other EZS.
I have AVDI MN026.

Cheers

[autobo]

Spare key not initialised.Leave key in ezs for 30 min. with igniton on

[armpower]

Hallo

Thanks for the tips.But i've tried to leave the key on EZS for a night.Today i leave inserted with light on, just to wake-up can line, but no Joy.

But my main problem , as described in my post, is the intermittent no start.
The first key unlock Esl and turn normally on EZS, but the engine no start.
The error is lost communication with Engine ECU.This code is memorized in ESP and Electric steering.When the fault came, diagnostic tool can't connect only with
engine Ecu.
I suspect a random error from Ezs not wake-up engine ecu.
Before changing Ezs I've asked some info.
Anyone have experienced similar problem?

Anyway thanks for your valuable help

Cheers

[vageric]

check in EPC if 1699051500 and 1695451508 are compatable with the car.

[armpower]

In online EPC 1695451508 and 1699051500 are unknow part number.
By the way on fast search on internet 1699051500 is EZS for A180Cdi manual transmission 2010 year and also B-Class 180Cdi.SAme specs of my car.
1695451508 have a missing connector pin where the original have small black connector (two brown brown-black wires) these wires go to diagnostic socket.

[vageric]

epc have to give if the part # from the ezs is compatible.
if it not list it then is not compatible.

[armpower]

In online EPC 1695451508 and 1699051500 are unknow part number.
By the way original EZS have 1695451908 (on EPC unknow number) but with chassis number the resulting part number is 1695452008.
The Valid EZS for this car are 1695451608 changed in 1695451208 changed in 1695451808 finally changed in 1695452008
I suspect the EZS number stamped on EZS unit is not a valid part number to find on EPC.Seems you have to add 1 unit to the EZS number to find the correct part.
Es: 1695451508 is 1695451608 1699051500 to 1699051600 1695451908 to 1695452008.I've checked and seems to work.
Just to add some more info

[Shmortz]

Edit: I had such problem long time ago, it was flash in EZS MCU, only one different adress was causing simular problems. Faulty EZS was 1695451508 with 3L40K MCU.
You should try to find good flash for your EZS and and compare with your.

[armpower]

Hallo

Just to close the thread I've resolved the problem.
Yesterday the customer have the time to leave the car so I have enough time to check all with a bit of patience and time.
The fault is described above.
I've rechecked all the positive and ground.All Ok.But...
Sometimes from relais K100L , the voltage directed to the ecu , during first key rotating,drop (probably carbonized contact inside) enough to cause a lost in communication with Ecu.
Sorry to have misdiagnosed the problem.
So the solution is to replace the relais.

Thanks to all

[Xtreme0303]

Hallo

Just to close the thread I've resolved the problem.
Yesterday the customer have the time to leave the car so I have enough time to check all with a bit of patience and time.
The fault is described above.
I've rechecked all the positive and ground.All Ok.But...
Sometimes from relais K100L , the voltage directed to the ecu , during first key rotating,drop (probably carbonized contact inside) enough to cause a lost in communication with Ecu.
Sorry to have misdiagnosed the problem.
So the solution is to replace the relais.

Thanks to all

Hello, I have the same issue...can you tell me please which one is the relais? Thanks a lot