2005 c180k maf/ecu fault

[del635]

Got a merc here, I'm the 4th person to have this last man 'thought' it needed an ecu, runs eml on all the time and p0102 code, not rough but poor power/mpg.
I removed the maf and refitted a brand new siemens/vdo one as the 'hot' wires were obviously broke but was never confident due to the voltages, made no difference. Theres a 12v supply from the fuse but the earth has a little resistance (220 ohm) and theres no 5v live. Checked the wiring from sensor to ecu plug (its real handy) and all is fine 0 resistance plug to plug and no shorts. The engine is too new (271) for the oil in loom problem and theres no signs of it. Ecu is siemens sim4.
Ecu time? Anyway to fix this possibly the same idea inside as simtek hybrid? Or maybe I'm missing something?

[Larue]

Got a merc here, I'm the 4th person to have this last man 'thought' it needed an ecu, runs eml on all the time and p0102 code, not rough but poor power/mpg.
I removed the maf and refitted a brand new siemens/vdo one as the 'hot' wires were obviously broke but was never confident due to the voltages, made no difference. Theres a 12v supply from the fuse but the earth has a little resistance (220 ohm) and theres no 5v live. Checked the wiring from sensor to ecu plug (its real handy) and all is fine 0 resistance plug to plug and no shorts. The engine is too new (271) for the oil in loom problem and theres no signs of it. Ecu is siemens sim4.
Ecu time? Anyway to fix this possibly the same idea inside as simtek hybrid? Or maybe I'm missing something?
Thereis only one thing what I can say.....if,if and once more if wiring from sensor to ECU is OK next possibility is ECU fault....
I think You are not alone with this fault in whole automotive world....have seen that before couple times.....
Cheers!:ciao:

[del635]

Its alot of money lol

[Meat-Head]

*CONFUSED* Cut the 5 volt feed wire to maf - download a 7805 regulator and 2 100uf 16v caps, upload that, see what damage it causes

[del635]

Theres no 5v feed thats the problem! Earth is not good either.
Can a second hand ecu be coded ok? What would we need as kit?

[Meat-Head]

Theres no 5v feed thats the problem! Earth is not good either.


sorry, just HAD to remove pdf reader off this pc look at this see if it makes sense

http://www.spelektroniikka.fi/kuvat/regu.pdf

http://dawn.singlespoon.org.au/7805.gifhttp://electronic-circuit.net/wp-content/uploads/2010/10/7805-regulator-ic.jpg

[del635]

So....give it its own 5v and hope the signal circut inside the ecu isnt fried?
?612+vat from merc btw, then an hour or 2 at 95+vat, hmmmmm

[Meat-Head]

So....give it its own 5v and hope the signal circut inside the ecu isnt fried?

1) It's not your car
2) If you fry it, deny it - ( part of badgaragescheme.com rules)
3) Cut the '5 volt' (dead) wire before you feed it
4) ASSUMING the airflow has a '12 volt' ground and 12 volt pos there
anyway for the 'Wheatstone bridge'
5) Better a DK member making a killing than a dealer
6) ASSUMING you are over 21 years old and can read/write?
if so then do above with a smegulater, if you are less than 21
and are unable to read and write chances are you work for a main
dealer anyway

HTH

Meat.