E320 missing

[imadoofus]

I plugged it in just now.

The light doesn't blip at all

It goes on when I press the red button (as it should), and when I release the button, there are no more blips. No faults.

 

[Mark300SL]

Exactly the same as mine - just before it fried the ECU
No errors - but inconsistent problems that would clear and then come back the next time it was started.

All of a sudden it wouldnt run at all and all 6 injector were maxxed out permanently -ooooops!


Mark

 

[kth286]

Imadoofus

OK

* one lead (black earth) into number 1 socket

* one lead (red power) into number 16 socket

* one lead (yellow diagnostic) into number 8 socket.

* switch on ignition to number 2 (dash warning lights on)

* press code reader switch for 2/3 seconds and release.

* wait for the code reader LED to blip - count how many and write down.

* press code reader switch again for 2/3 seconds and release.

* wait for the code reader LED to blip - count how many and write down

* repeat process until only one blip is obtained. That is the end.


Let us know how many sequences of blips and what each blip count is.

 

[imadoofus]

I did all that. I got no blips. I'll go and do it again.

 

[imadoofus]

Done it again. No blips. Nothing.

I know the tester is working, because I still get my pax airbag fault.

 

[imadoofus]

Exactly the same as mine - just before it fried the ECU

Oh. Great.

Well when MB come back tomorrow (?) with a price on my loom, I'll buy it and then fit it when I'm back in the UK in August.

Car won't be used before then, so hopefully I'll get away with it. Presumably, with a new loom, an ECU fault would register with my diag tester?

 

[kth286]

Imadoofus

You must always get one blip to show that the computer is free of logged faults.

So, on socket 6 you are getting blips for SRS system - how many blips ??

 

[imadoofus]

On socket six I get three blips. On socket 8 I get none.

 

[kth286]

Imadoofus

So, are you able to clear those 3 blips (on pin 6) until you get a clear signal (one blip).

 

[Dieselman]

Your ECU isn't fried if you have an intermittant fault. What fries the ECU is the harness shorting to Gnd.

As the harness is pretty expensive and you don't immediately need the car I would go for a repair either with heat shrink or by letting in new cables.

I'd also be tempted to fit fuses to the ECU output cables, that way a short can't damage the ECU.

An alternative supplier for a harness might be http://www.autosparks.co.uk/

 

[imadoofus]

As the harness is pretty expensive and you don't immediately need the car I would go for a repair either with heat shrink or by letting in new cables.

I'd also be tempted to fit fuses to the ECU output cables, that way a short can't damage the ECU.

You may have noticed that my forum name isn't Dieselman, it's imadoofus.

The heat shrink method sounds simple, but there's going to be a fair bit of cutting cables and resoldering. I am afraid of not having enough spare length in my cable. Snarf.

AFAIK, there are about a million and six cables coming off the ECU. Am I suposed to fit a fuse to each one, or can I do it en mass? What rating do I need? Where can I get a fuseholder big enough to take a cable like a baby's forearm?



TIA

PJ

 

[Dieselman]

You only need to strip the outer fabric sheathing and cut the cable near the bulkhead, slide heatshrink over the existing insulation, solder the cut cable back together, then shrink away.

Only the feeds to the coils need to be fused.

 

[imadoofus]

You make it sound so easy...

I can cut. I can solder. I can apply heat shrink.

But there's an awful lot of wires

What the heck. Maybe I'll have a go anyway. What's the worst that can happen?

 

[Dieselman]

What the heck. Maybe I'll have a go anyway. What's the worst that can happen?

Fizzzz...BANG.

You only need to do the ones that go across to the engine, and maybe only those that go nearer the hotter parts.

 

[c240yaz]

Just an addtional check. Go somewhere completely dark. Open the bonnet, some times you can see electrical tracking, if all insulation is removed,

 

[Ade B]

Jay. I don't expect you to remember this, but at my last MOT, I got an Emissions Check report which says "For Non-Catalyst Equipped Vehicles". Does that definitely mean I don't have a cat, or is it possible I got the wrong form?

I got this on my last MOT cert and suddenly thought I had the 'most powerful' version of the C124 - was quite disappointed to then find it was the cat which had been bottoming out on speed bumps..

Re the loom (smug in the knowledge my older less desirable CE doesn't suffer this particular problem ) I hope you get it sorted soon.

Ade (waiting for the next mechanical/electrical challenge).

 

[Mark300SL]

Well when MB come back tomorrow (?) with a price on my loom, I'll buy it and then fit it when I'm back in the UK in August.

Loom is about £600 for almost every M104 version (Ecu is £1200 in my case!)

You make it sound so easy...

I can cut. I can solder. I can apply heat shrink.

But there's an awful lot of wires

What the heck. Maybe I'll have a go anyway. What's the worst that can happen?

Its about 8 hrs work on a sunday, Plus about £20 for the coilpack wires from Mercedes, £30 for heatshrink

So £550/8 = £63 ish per hr makes me feel good - of course you may have actually made a few sucessful appointments today and may decide to just buy the harness

Feel free to drop me a line if you want to discuss this at all


Mark

 

[imadoofus]

you may have actually made a few sucessful appointments today and may decide to just buy the harness

Feel free to drop me a line if you want to discuss this at all

Har-de-har!



Thanks Mark.

I'm away for a couple of weeks, but in early August, you may well be hearing from me...

 

[kth286]

There is an official repair kit available from Mercedes nowadays, so new loom not normally required.

It is normally only the 3 coils feeds that short out (as if that was not bad enough).

It is where the wires emerge from the thick rubber strapping under the engine top cover, and go to the 3 coil connections.

You need to gently trim back the outer loose covering with small scissors to reveal the actual insulated wires. You will likely find the wires insulation cracked in several places and brittle.

What happens is that a spark plug change requires the stiff brittle wires to be moved out of the way and hence they crack.

At some future time you go to start engine, some wires short out and blow a coil (and possibly the main ECU with it).

A blown coil immediately renders 2 cylinders innactive - so you definately know about it.

Yours does not sound that bad - hence trying to establish actual fault codes registered.

 

[c240yaz]

Loom is about £600 for almost every M104 version (Ecu is £1200 in my case!)




Its about 8 hrs work on a sunday, Plus about £20 for the coilpack wires from Mercedes, £30 for heatshrink

So £550/8 = £63 ish per hr makes me feel good - of course you may have actually made a few sucessful appointments today and may decide to just buy the harness

Feel free to drop me a line if you want to discuss this at all


Mark

I would trade it in before I pay this. I must be in the minority here, but some of you guys must be really wealthy ?

Need a Chaufer ? I am available at £40K PA. This will also include full valet daily in my contract to you, as well as being a time served mech, which a lot of forum members do not realise.

PS. I do not do vegi oil in Diesels, it is against my teachings.