C350cdi 2010 v6 Not Starting, Constant fuse 23 blow.

[tony-er8kp]

Hi All,

I have a problem, where my car is not starting there was no codes on the computer we tried to connect seems we cannot get that far in.

Fuse 23 is blown, and every-time I put a new fuse in it blows straight away.
fuse chart tell me it is 'engine electronics' but nothing more than that, can someone help in what does fuse 23 actually protect?

The radio doesn't turn on but windows go up an down, the speedo computer is on, the wipers work.
Does anyone know what it could be could it be the ECU has gone?

Seems like there is a short somewhere causing it to blow immediately, but i haven't got a clue, can anyone please enlighten me.

Thanks,

[paintman]

You could try the suggestion by pistnbroke here: http://forum.lro.com/viewtopic.php?f=48&t=9250...
AIUI he is a vehicle electrical specialist but, as always, at your own risk.

[lucas8277]

Hi have you tried disconnecting the glow plug output stage at the front of the engine or the inlet port shut off motor in the middle of the v ?

[tony-er8kp]

Its actually fuse 24... disconnected the glowplug module and still no difference.
Going to try the inlet motor tomorrow... does anyone actually know what fuse 24 protects... i assume its inlet.

[lucas8277]

Hi I think that is the fuse for the inlet port shutoff motor it also is the fuse for the waste gate , easiest way to tell is turn on the ignition and watch to see if the waste gate arm moves .

[tony-er8kp]

Just got it recovered to the garage goint to tell him that advice.

[tony-er8kp]

But if its the inlet motor shouldnt the car stay on and drive in limp mode?

My cars engine management light is even on and doesnt start... but defo electrical fault.

[lucas8277]

It depends , if the inlet port shut off motor has a dead short inside the fuse would blow . Or if the inlet ports are seized . The motor may be ok but the current draw will be high as the motor has to work harder to try to move the ports .

[Jimmyarm]

On the straight six diesels, when the inlet flapper valve motor goes it blows a similar fuse that feeds power to it and the engine management systems. You can't communicate with the ECU to pull fault codes as it has no power.

To find out what is causing it, you need a Mercedes wiring diagram for your model and go around disconnecting each module the fuse protects in turn until the new fuse you put in each time doesn't blow.

It probably is the flapper valve thing though

[tony-er8kp]

[tony-er8kp]

The guy says charging £400 exc. Parts to replace motor and clean manifold etc...

[lucas8277]

Thought as much least it's sorted

[selnic]

Out of interest is this the OM642 engine by any chance?

[tony-er8kp]

Engine wise it has 231BHP. which i assume is OM642

Another question regarding this scenario:

is there two of the below plastic bits or just one? image shown below and do dealers give them separate or with the part.



Also i lost the torque screw for the attachable metal slider... do dealers give that or do i need to order the whole motor again.

Also, what are the part no.s for:

1. The new Rubber seal for the one that needs to replaced
2. Motor that needs replacing.
3. the plastic bit
4. The screw

Thanks,

[selnic]

Sorry about the delay getting back to this, if it is the OM642 engine there is a whole load of info about disconnecting the swirl motor, and fitting a resistor across the plug, however looking at your pictures I think it may have gone beyond that part already.
Here is one of the links from when I did mine.

http://www.mbclub.co.uk/forums/engine/149185-swirl...

[tony-er8kp]

Look guys i'm really really stuck, i have lost that screw in the above picture which goes into the metal clip, dealers do not stock that screw.

It is a Torque screw flat... all i have is the metal which has the thread... i am still looking for screw.

Dealers say i would need the whole Manifold on the RHS as the metal piece is part of that with the screw and does not come separate. Does any one know the best solution or a place i can get the screw made in Birmingham based on thread, but wouldn't length be n issue and cant remember if the bottom was flat or pointed?

Thanks Selnic for that info, but I'm not sure if i should not fit a new one in as i am not fully experienced with resistors etc... and don't want anything else to blow.

I just need a screw which is lost or £1500 for a new manifold... Any help please

[tony-er8kp]

---

SOLVED---------------------

it was a M5 torx bolt.

Thanks