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Hello !
hope you can help me out, I have tried to search the internett and this forum for several days without any good result.
i have a
W212, E220,
I live in Norway.
my problem is the following:
Fuse 7, 20A (marked starter) blows when i turn the key all the way to start the car.
Nothing is happening, no noise from the starter nothing, the car does not try to start.
but if I replace the fuse the car worked fine for a week.
So after driving to a friends house, I was going home and the car did not start again.
all lights are good in the dash.
no noise from starter, i go and check the fuse again and it’s blow’n.
replace fuse and the car is good again.....
I am not sure if it’s the starter and I dont want to replace that if something else is hausing this problem.
the battery got replaced while troubleshooting the car the first time it didn’t start.
Without looking at any schematic, a 20amp fuse if labeled as STARTER is for the solenoid of the starter and not the starter itself which is 100+ amps minimum.
Without looking at any schematic, a 20amp fuse if labeled as STARTER is for the solenoid of the starter and not the starter itself which is 100+ amps minimum.
exactly 👍👍
If you want to fix what is blowing your fuse, you're going to need schematics to see what exactly this line is feeding, then you can make good guesses as to what to do.
It could be your starter solenoid... -or water found its way into your SAM... The good thing is you have it pretty well cornered as where to concentrate.
Everything else about troubleshooting still apply... Scanner, TSB's, CTEK float.
I'll take a look today if my E350 diagram shows a similar circuit
🤞
Last edited by CaliBenzDriver; 05-18-2021 at 12:15 PM.
First of all, thank you all for taking your time to help me out.
So i’m gonna do a inspection of my SAM, water/corrotion etc and i’m going to replace the relay you have marked in the image.
I only understood that F7 is terminal 15 in the Diagram and it’s connected through the relay you marked.
If there was more information I should have understood by the attachments please explain it on a simpler level XD
Just in case you forgot to say... is your E220 gasoline engine -or a DIESEL with a string of glow-plugs ?
Do you have a DVM/Tester to ohm things out... very useful to own one today for this short.
If your not in the mood to get dirty in a hurry, let's work from top side by pulling F-SAM relay M.
Ohm out the starter coil circuit#50 and expect to read a resistor greater than 0.65Ohms.
-- Lower than 0.65Ohms that is your short
-- Higher around 0.8...1.2Ohms : you're good
Next I would try to unplug your starter solenoid to try and confirm that's your short-circuit or not. It may be the line itself is grounding somewhere.
The outcome is to figure what is reading low.
starter control relay
> Front-SAM schematic:
- Fuse 7 labeled as "STARTER RELAY" - Fuse:20Amps (Diag:N10/1F7 /Loc: 17A)
- "kM" is the intermediate relay that commands the coil of your starter. (K like Komand)
- Fuse7 feeds the load side of kM... ie. the starter coil itself
> There is a spaghetti :
- The load side of M known as Circuit#50 goes off the page obviously towards to starter... need more engine info + diagram
- It merges with a one way circuit#31 through a diode connected on missing diagram "PE 54.21-P-2106DAG"... (glow plug controller triggering the starter??) missing engine specifics
Todays conclusion is we knew the problem was involved with starter... a cooked coil is kinda weird.. contacts yes but coil... what do you think? shorted line?
------------------------------
If anyone is interested in quickly disabling his car for personal reasons...:
F-SAM fuse#7 disables the engine Starter
The K2 main relay connector on top of preFuse effectively puts both SAMs to sleep.
Last edited by CaliBenzDriver; 05-18-2021 at 09:53 PM.
Reason: digging around schematic
Just in case you forgot to say... is your E220 gasoline engine -or a DIESEL with a string of glow-plugs ?
Do you have a DVM/Tester to ohm things out... very useful to own one today for this short.
If your not in the mood to get dirty in a hurry, let's work from top side by pulling F-SAM relay M.
Ohm out the starter coil circuit#50 and expect to read a resistor greater than 0.65Ohms.
-- Lower than 0.65Ohms that is your short
-- Higher around 0.8...1.2Ohms : you're good
Next I would try to unplug your starter solenoid to try and confirm that's your short-circuit or not. It may be the line itself is grounding somewhere.
The outcome is to figure what is reading low.
starter control relay
> Front-SAM schematic:
- Fuse 7 labeled as "STARTER RELAY" - Fuse:20Amps (Diag:N10/1F7 /Loc: 17A)
- "kM" is the intermediate relay that commands the coil of your starter. (K like Komand)
- Fuse7 feeds the load side of kM... ie. the starter coil itself
> There is a spaghetti :
- The load side of M known as Circuit#50 goes off the page obviously towards to starter... need more engine info + diagram
- It merges with a one way circuit#31 through a diode connected on missing diagram "PE 54.21-P-2106DAG"... (glow plug controller triggering the starter??) missing engine specifics
Todays conclusion is we knew the problem was involved with starter... a cooked coil is kinda weird.. contacts yes but coil... what do you think? shorted line?
------------------------------
If anyone is interested in quickly disabling his car for personal reasons...:
F-SAM fuse#7 disables the engine Starter
The K2 main relay connector on top of preFuse effectively puts both SAMs to sleep.
Hey, i’m gonna read through your post and come back with the result.
i have a DMT yes
I am more convinced it might be a Busted starter or solenoid.
the starter sound is normal when it works.
it might be the Line is shorting to ground somewhere, but last time the fuse blew the car stood completely still and all i did was replacing the fuse.
what i think is wierd is that, the car does work after the fuse is changed, then after a while the fuse blows again. Could be a day or could be a week.
therefor i think it will be difficult to do a measurement and find the problem, atleast now when the car is working.
E220 Diesel with glow plugs yeah.👍🏼
Last edited by ChristoffW212; 05-19-2021 at 01:06 AM.
Simple troubleshooting below............
Unplug terminal/connectors one at a time and crank..... in the order 1 to 4 as marked below, to verify where the short-circuit actually happen.
If 1 to 4 done and still a short-circuit condition exist, then you take a look at N10/1 Front Sam.
Good luck...
ADD : You best inform your VIN code, because the wiring schematic variation is huge between different models + options, even for diesel.
Last edited by S-Prihadi; 05-19-2021 at 10:03 AM.
Reason: typo
05-18-2021, 04:58 AM
