Urgent help on EGR and ECU on WDF 639 Vito 3

[Cooperman1970]

Just checking my garage is correct here ...
I called out the AA when my Vito went into limp mode. Diagnostics indicated the following System : Engine control - E1F / Diesel EDC 17CP10-7P149A00 - EGR control motor 1. Error Message : Internal fault.P155D00 - Exhaust gas recirc. cooling sol. valve. Error Message : Component faulty.Loss of power, above fault codes stored, suspect egr valve fault, advised to take to garage for further investigation and repair.
The garage has fitted a new EGR valve but the fault is not clearing from the ECU. They have checked the wiring and this all seems to be good. They are indicating they will have to send the ECU off to Mercedes to get that checked.
This means I am going to be without my van for Christmas and looks like the trip back to Ireland to see the family could be off!!!
Does that seem correct? Is there anything else I can get them to try?
Cooperman!

 

[oigle]

Mongrel EGR's. PITA.

 

[Cooperman1970]

Isn't it just!

 

[M80]

Is you garage an MB specialist?
An MB main agent will likely mt your wallet.

Prior to sending the ECU off,
and btw I don't see MB would want that w/o the vehicle,
I would be looking for some one that can check the wiring from the ECU to the EGR.

I appreciate they say they have checked the wiring, but how?
W/o a diagram they wouldn't understand the pin outs at the ECU plug to test from, did they have that?

I would want to confirm a good connection at the EGR while the plug is being manipulated.

 

[M80]

A couple of simple checks,
Fuse 6, 40 & 41.
Checking that there is 12 volts at each of those fuses with ignition on would confirm the output from relays R1 and R4.

Confirm that this place is still operating, and that they are able to test your ECU. But tbh I think testing any ECU w/o the vehicle is a tall order.

ECU Testing

Delves Road

Heanor Industrial Estate

DE75 7SJ

01773 535 638

 

[Cooperman1970]

Is you garage an MB specialist?
An MB main agent will likely mt your wallet.

Prior to sending the ECU off,
and btw I don't see MB would want that w/o the vehicle,
I would be looking for some one that can check the wiring from the ECU to the EGR.

I appreciate they say they have checked the wiring, but how?
W/o a diagram they wouldn't understand the pin outs at the ECU plug to test from, did they have that?

I would want to confirm a good connection at the EGR while the plug is being manipulated.

Garage a German prestige specialist. I belive they have check the wiring from the circuitry diagrams.
Will ask the question thank you

 

[Cooperman1970]

A couple of simple checks,
Fuse 6, 40 & 41.
Checking that there is 12 volts at each of those fuses with ignition on would confirm the output from relays R1 and R4.

Confirm that this place is still operating, and that they are able to test your ECU. But tbh I think testing any ECU w/o the vehicle is a tall order.

ECU Testing

Delves Road

Heanor Industrial Estate

DE75 7SJ

01773 535 638

Thank you for your expert insights - have asked the question

 

[supernoodle]

Diesel EDC 17CP10-7P149A00 - EGR control motor 1. Error Message : Internal fault.P155D00 - Exhaust gas recirc. cooling sol. valve. Error Message : Component faulty

You're missing some spaces so people might have missed that's two faults

P149A00 - EGR control motor 1. Error Message : Internal fault

P155D00 - Exhaust gas recirc. cooling sol. valve. Error Message : Component faulty

They are two separate devices driven by separate pins. When you get two faults together you're unlikely to have two faulty components, you have to think what's common...and I don't mean ECU. It's rarely the ECU. That's just the stock answer when a garage doesn't know what to do.

I don't like that diag tool that's been used, I'd say they are not the MB descriptions, they are too vague. The ECU can't know an component is faulty, especially an EGR cooler solenoid. There is one pin connected to the ECU for this. It just knows voltage at the pin. When device is connected and solenoid is not commanded it expects to see battery voltage at the pin. When it commands the solenoid on it would expect to see pin close to 0v (ECU switches low side). If the pin is always at vbatt, it would think that there was a short circuit to power.
If the pin was always at 0v it would think that either the solenoid isn't connected or there is a short to ground. The point being ECU does discrete tests and would set a relevant fault.

With all that said, even without a decent description it should be possible to do some tests before throwing parts at it. The solenoid certainly just has a 12v supply (not from ECU) , the other side going to ECU as a low side switch. I'm pretty sure the MB EGRs have a 12v supply and just signal pin to ECU. So as already suggested, check the supplies. After all, if supply is bad, that would cause both to fail.

Sometimes it's useful to purposely induce errors, so disconnect the component, does the fault change? Short the signal pin to ground, short to vbatt (via a fuse or use a proper test probe), is there a change? This can help you understand what error state you are looking for.

With most decent diag tools you can control the actuators too. You can even replace the EGR cooler bypass with relay for testing, It makes it easy to hear if it's switching.