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MAF sensor replacements
- Thread starter BRABUS124
- Start date
Ouch - yeah, that one is toast. I've seen some aftermarket MAF's for sale on eBay but I have no idea what the quality or functionality is like... I wouldn't risk it unless you had no other options.
If you need replacement MAF's, I think Jono at Blue Ridge MB has some for sale.
If you need replacement MAF's, I think Jono at Blue Ridge MB has some for sale.
Does anyone know what part has done this melt down.? I guess the sensor it self is the stright stick in the middle of it. Then you have the sqaure wire string around it. Is that some sort of heat element? Og resistor?
And is that wire the cause of the heat damaged? Or is there another electrical thing around inside that brown plastic tube that are able to get hot by shorting or simular isues to melt the plastic.
I can find the spec sheet on 124 performance but it says 3 resistors and a "hybrid" box for the rest. There are also build in a temperature sensor as I read it and that could be the wire string inside... The wiring were toast so that would be something witch could have caused it to short something. The wires are all new now from Kurth I measured all wires to the socket of the LH module that's all good no shorting now for sure. So the error code 4 in the LH module defently comes from the damaged MAF sensor. I would like to verify it be measure the MAF but I don't have anything to compare it to.
Hardest thing will defently to find another part. So I might have to dig into restoring or at least trying to work with the one I have even though its a highly non repairable unit in the form it's done. Buy if I could somehow cheat the module to not see a short or cut connection. I might be able to get it run at least. But it depends what's shorted/cut
And is that wire the cause of the heat damaged? Or is there another electrical thing around inside that brown plastic tube that are able to get hot by shorting or simular isues to melt the plastic.
I can find the spec sheet on 124 performance but it says 3 resistors and a "hybrid" box for the rest. There are also build in a temperature sensor as I read it and that could be the wire string inside... The wiring were toast so that would be something witch could have caused it to short something. The wires are all new now from Kurth I measured all wires to the socket of the LH module that's all good no shorting now for sure. So the error code 4 in the LH module defently comes from the damaged MAF sensor. I would like to verify it be measure the MAF but I don't have anything to compare it to.
Hardest thing will defently to find another part. So I might have to dig into restoring or at least trying to work with the one I have even though its a highly non repairable unit in the form it's done. Buy if I could somehow cheat the module to not see a short or cut connection. I might be able to get it run at least. But it depends what's shorted/cut
I have been lucky once reapiring such problem with spare parts taken from Volvo LH MAF. Bosch part no for donor MAF was 0280212016. I took the complete internal channel with LH wire, temp sensor and other hardware and transplanted it to the V8 MAF. Worth to give it a try as Volvo MAFs were much cheaper than MB MAFs.
That burnt marks are caused by this part failing.
That burnt marks are caused by this part failing.
Attachments
Hi Arnt. All the guts i swapped over were the same between the volvo and MB MAF. I obviously didnt use the volvo electronics as the built in connection was different and i guess the calibration data would be different for less-than-8-cyl motor as well. I reused the MB electronics and attached the volvo sensing part as it looked the same. In the end motor for which this MAF was built ran fine with no codes so i considered it a win and so im sharing this experience.
My part is acturly for a V12 600 SL but simular part.
What is that part doing your holding in your hand in the picture?
From what i have read online its either temperature thermistor or heating resistor but bc its usually burnt on V12 MAFs i would say its the heating resistor.
I have two M120 powered cars and im really not looking forward to have to deal with this issue. The 600 MAF prices are crazy. Just as crazy as R129s V12 EGASes
I have two M120 powered cars and im really not looking forward to have to deal with this issue. The 600 MAF prices are crazy. Just as crazy as R129s V12 EGASes
The LH does a burn off function to keep the hot wire free of contamination. Possible the burn off cycle didn’t turn off. I have never seen this type of failure but I know when the burn off function is activated the wire glows red hot for a split second.Back in the, days Bosch rebuild the, MAF.
What are we left with when those, dies.
I got a code 4 on the LH module. Saying MAF sensor voltage, supply is shorted or open circuit.
When looking inside it looks really burned.
What happened
Yes that's eksactly my thought as I knew this as well. And my theory is that the reason this function might not turn of, is the time cycle set in the LH module by an RC time circuit constant.
And when these modules goes bad as we/I see alot these days with the capacitor failing specially the axial blue one they makes all kinds of strange faults. And this could be one of them. So I opened op both LH module on the 600 and replaced all 8 capacitors 6 light blue 1 axial blue and a green tantal with the bad hapoid of shorting when going bad instead of loosing it's capacity/connection.
Crasy great info. The best once I got were these.
Yes the nu er i need is for the M120 V12
Not the same as the 500 they are difrent build. I think I'm going to try the non original replacement. That my favorite nly option for now.
Update
Bought the German companies afhermarked types for a 600 engine. It removed the fault from LH modules and I could clear the codes. And make the LH readaptation thing. But that's were the glory stopped.
As long as it were in idel no problem. But as soon as you touched the throttle the car stalled or hesitated to take rpm. Like it dident got the correct info from the new sensors.
I reinstalled the old working MAF that looked burned. And then it could take the rpm again. But threw me the fault codes again.
I sent the chaina MAFs back to the dealer in Germany and had a voucher for the amount
Bought the German companies afhermarked types for a 600 engine. It removed the fault from LH modules and I could clear the codes. And make the LH readaptation thing. But that's were the glory stopped.
As long as it were in idel no problem. But as soon as you touched the throttle the car stalled or hesitated to take rpm. Like it dident got the correct info from the new sensors.
I reinstalled the old working MAF that looked burned. And then it could take the rpm again. But threw me the fault codes again.
I sent the chaina MAFs back to the dealer in Germany and had a voucher for the amount
I rarely post here on this forum, but reading with interest, on the circuit side of this issue of the MAF.
Asking:
With the damaged MAF, could you not replace 'the damaged component' perhaps the measuring resistor in the MAF with a correct replacement?
From personal experience, my local goto circuitboard man, has repaired several of my relays and radio circuit boards and such where the component and/or the trace lines were damaged or burnt.
Asking:
With the damaged MAF, could you not replace 'the damaged component' perhaps the measuring resistor in the MAF with a correct replacement?
From personal experience, my local goto circuitboard man, has repaired several of my relays and radio circuit boards and such where the component and/or the trace lines were damaged or burnt.
I understand your thoughts. But the hybryd unit board that sits on top of the MAFs are not eksactly the kind of electronics board you can work on. I were just able to read all resistors were dead. So something burned the complete unit off including the one they called the hybrid controller. I am skilled electronic technician my self and that MAF were not savable. They of cause do this to prevent copy products. And these from bosch are refined precision components and lab build units. Something I would have it hard to beleave could even be coming out of China unless pretty poor build with no 100% equality in working. As I found out.
Theres a reason bosch priced them like 5X higher than other brands of no names.
So sadly they were a scam in practice.
The resistor and heat module are no challange to copy. It's the Hybrid unit on the top theres the problem. Kind of like the EZL on a M104 no one has ever been able to copy those and by a look inside the chip is put in clear soft silicone with nidle thin wires that are not soldered on to it. No they are the type that are shot welded to it. And it runs can bus in them as well. I guess the 500 KE and LH engines are the same. That's also baked in epoxy for no one to find out how they work.
I wonder if bosch still has the programing device for the EZL. Only bosch did the AMG EZL for 104.980 and 119 as I recall. You won't find Siemens EZL in these. So bosch programed the to have higher more aggressive ignition on full load hence they write in a sticker in the gaslit "nur bleifrei super (PLUS) That's a minimum of 98 octane for the time.
Thanks for the proper explanation giving a good or better understanding on how the LH works.
Bosch do probably still have the needed equipment for programming these units, but MB doesn't allow them to use it because they are commited to the Green Deal and phasing out fossile fuel driven cars. Or put more correctly - the case is not the engines themself, it's the level and type of emission they create.
Bosch do probably still have the needed equipment for programming these units, but MB doesn't allow them to use it because they are commited to the Green Deal and phasing out fossile fuel driven cars. Or put more correctly - the case is not the engines themself, it's the level and type of emission they create.
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