Mercedes W212 E250 CDI not starting fan running at high speed need help
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Joined: Jun 2021
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W212 E300 Avantgarde
Mercedes W212 E250 CDI not starting fan running at high speed need help
Hi
I have a 2010 Mercedes E 250 CDI which was driving fine up until three weeks ago when one morning it suddenly refused to crank and is giving a bunch of error messages on the information cluster.
when you turn the ignition all the dash and console lights come on but further twisting to start it results in nothing from the engine, not even a click.
I have attached a video showing the problem as well
I have checked prefuse box and found nothing burnt or broken in there. Same goes for the front fuse box and the one in the trunk. All the fuses and relays are intact and visibly there is nothing wrong with the ECU and not rattle if you shake it. Have tried two different new batteries and still nothing.
The only work that was done on the car was around three months ago when the fan belt , battery and all the filters were changed after which it ran fine till this issue appeared out of nowhere .
Would appreciate any help from anyone who has experience this problem before or can offer any advise as to where we should be looking to trouble shoot this problem.
Thanks in advance
I have a 2010 Mercedes E 250 CDI which was driving fine up until three weeks ago when one morning it suddenly refused to crank and is giving a bunch of error messages on the information cluster.
when you turn the ignition all the dash and console lights come on but further twisting to start it results in nothing from the engine, not even a click.
I have attached a video showing the problem as well
I have checked prefuse box and found nothing burnt or broken in there. Same goes for the front fuse box and the one in the trunk. All the fuses and relays are intact and visibly there is nothing wrong with the ECU and not rattle if you shake it. Have tried two different new batteries and still nothing.
The only work that was done on the car was around three months ago when the fan belt , battery and all the filters were changed after which it ran fine till this issue appeared out of nowhere .
Would appreciate any help from anyone who has experience this problem before or can offer any advise as to where we should be looking to trouble shoot this problem.
Thanks in advance
Out Of Control!!
Joined: Apr 2019
Posts: 11,924
Likes: 6,776
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
You're in luck! You have reached the place where you can quickly find the fix for your diesel Benz.
Your full speed fan behavior is a common tell-tale sign of low power.
Being a true gasoline guy brought up on carburators only... I can say if you hit the search button a few times, you'll reward yourself with exactly all you need.
We have many great members with borad knowledge including direct injected Diesels.
Do you have an ODB2 SCANNER and electrical skills to troubleshoot PreFuse relays??
Your full speed fan behavior is a common tell-tale sign of low power.
Being a true gasoline guy brought up on carburators only... I can say if you hit the search button a few times, you'll reward yourself with exactly all you need.
We have many great members with borad knowledge including direct injected Diesels.
Do you have an ODB2 SCANNER and electrical skills to troubleshoot PreFuse relays??
MBWorld Fanatic!
Joined: Jun 2020
Posts: 1,363
Likes: 1,012
'11 E350, '11 E550, '98 M3, '95 E320
I believe the engine fan defaults to full speed when either the signal from the engine ECU is corrupted or not present, Climate control signal is corrupted or not present and/or the fan module is a bad. Besides checking for good power and ground.
Since you can’t start the car either... you should find something with Xentry to check drive authorization and monitor fan request to verify problem.
Since fan is full speed AND engine doesn’t start, I’d suspect problem with engine ecu and/or associated wiring.
Since you can’t start the car either... you should find something with Xentry to check drive authorization and monitor fan request to verify problem.
Since fan is full speed AND engine doesn’t start, I’d suspect problem with engine ecu and/or associated wiring.
