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Lou P. master tech
Lou P. master tech, Mercedes Technician
Category: Mercedes
Satisfied Customers: 4966
Experience:  15 years master certified 100% fix rate and have access to factory radio codes, wiring, and instructions.
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Lou P, i installed an ecm with immoblizer from the original

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Lou P,
i installed an ecm with immoblizer from the original ecm installed. Now there is still no crank. Immobilzer is recognized on my MB ll scanner with all authorizations to start the car. I replaced the starter because there is power under load when testing with a power pro probe2. The purple wire to the starter reads 0.0 while key is turned to start. The starter housing also reads 0.0. The big wire reads 12.5. The starter relay and fuse changed.On the relay socket, i get the following readings with key in cranking position: socket 1=12.4v, socket 2= 3.4v, socket 3=0.0v, socket 5=12.3v. The scanner showed code 9051, 9052 consumer shut off stage 2. I will recheck for more codes under the "actual values" of each component. But the test for all dtc
shows no fault codes on the top reads.

Hello, my name is***** and i will do my best to assist you.I am going over your story now and will reply back soon with some info,thanks!

Customer: replied 1 month ago.
Lou, i'll be out until friday morning. Hopefully i can get the car started that day with your help.
Patrick
Oh ok , I'll see what Info I can send until then for you

double check fuses 43 44 57 59

if you are getting 3.4volts out of 2 then there can be a issue with the ecm, you should have 2 positive a and 2 grounds on the relay.

Lou P. master tech and 2 other Mercedes Specialists are ready to help you
Customer: replied 1 month ago.
Ok im back. the fuses are good. which 2 slots should be positive? It looks like i have 3 positive reads from the starter relay ports. here.s a shot of an actual value. There was no DTC's that came up. Another one was :9021 fault in CAN communication with control unit A1 instrument cluster .9027 CAN communication is faulty
Customer: replied 1 month ago.
any ideas?

circuit 50 is cranking , try that value again with cranking the key.

my diagrams have been down last two days. sorry for no reply.

can you give me the entire back story, i cannot see any other of your chats to see the history of the car.

I will do what I can to help.

Lou

Customer: replied 1 month ago.
ok from the top. i installed an ecm with immoblizer from the original ecm installed. Now there is still no crank. Immobilzer is recognized on my MB ll scanner with all authorizations to start the car. I replaced the starter because there is power under load when testing with a power pro probe2. The purplewire to the starter reads 0.0 while key is turned to start. The starter housing also reads 0.0. The big wire reads 12.5. The starter relay and fuse changed.On the relay socket, i get the following readings with key in cranking position: socket 1=12.4v, socket 2= 3.4v, socket 3=0.0v, socket 5=12.3v. The scanner showed code 9051, 9052 consumer shut off stage 2. I will recheck for more codes under the "actual values" of each component. But the test for all dtc shows no fault codes on the top reads.
--changed starter, still no crank
--purple wire to starter reads 0.0 volts while turning key, big wire reads 12.4, using power pro probe2
Lou says:double check fuses 43 44 57 59 if you are getting 3.4volts out of 2 then there can be a issue with the ecm, you should have 2 positive a and 2 grounds on the relay.
--Ok im back. the fuses are good. which 2 slots should be positive? It looks like i have 3 positive reads from the starter relay ports. here.s a shot of an actual value. There was no top DTC's that came up. An actual value under "central command center" read was :9021 fault in CAN communication with control unit A1 instrument cluster .9027 CAN communication is faulty

ok, i guess the big question and answer I was missing was WHY did you replace the ecm and swap chips?

was it because of the same issue?

i just want to get the whole scenario so that way we are not chasing a ghost.

with the scanner on the eis value of the screen shot that you sent me, we need to see if circuit 50 goes to on when attempting to crank the engine, if we are then we know the ignition switch is ok.

also does the dash show the correct gear? P for park?

Customer: replied 1 month ago.
Lou, yes the 2nd circuit 50 goes to on temporary when i turn the key to start. P shows on the dash board.
To answer your other question, i replaced the ecm cause i sent my original one to be rebuilt and they diagnosed it as non repairable because of capacitor 429 or something. The car would not start in 100 degree weather after running. No signal to the fuel pump, it would just crank. I changed the cps 2 times. It would only start in the morning. After a while, no crank. Thats where we are today.
I am going to accept the offer of calling you the next time we are online same time. i guess thats how it works. Too much time has passed by. The car stopped running back in june.

ok, so there was a bulletin for the issue you had and the fix was a new ecm.

i think something happened with the swap of the chip.

it may be in your best interest to send both ecms out and have the swap checked and maybe corrected?

i think we are fighting something that the scanner cannot see.

Customer: replied 1 month ago.
ok i'll get the ecm checked. Disregard the live talk request.
Thanks
Customer: replied 1 month ago.
ok thanks

no problem.