The Magnetti Marelli ETM. Which cars have it?

[abscate]

For reference

1999-2002 non turbo models
1999-2001 turbo models

BI fuel models in P2 2001-2007 per yagger

Use the Italian throttle body referenced in this Forum

[precopster]

Part numbers affected: 36001822, 8644347, 8644346, 9186793, 9207831, 9497244, 36050563

Models affected:

1999-2001 S70, XC70, S80

1999-2002 C70

2000 & 2001 S60 turbo

1999, 2000 & 2001 V70 turbo

36001821, 8644344, 8644345
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Part numbers affected: 36001821, 8644344, 8644345, 36050564

Models affected:

2000 & 2001 S60 non turbo

2000 & 2001 V70 non turbo

[xHeart]

Our 2001 V70XC appears to be on a white label Marelli. Details coming.

[xHeart]

The replacement ETM is yellow label.

The original white label was replaced a while ago with 146,000 miles on it -- but wasn't among the affected PN.

More here: viewtopic.php?f=9&t=60981&p=312472

[mrbrian200]

Note that the newer Bosch type throttle bodies aren't 'perfect' either - merely they are cheaper and easier to replace. Probably 1 in 4 problems I see in here where people with newer model years are getting MAF and/or idle and fuel trim issues I put the throttle body high on the suspect list. These are a little tricker to diagnose as in my experience the engine computer doesn't trigger a throttle body specific DTC unless the position sensor has gone bad or the throttle plate is stuck/won't move at all. There is a reverse DC that can be applied to the stepper motor. This can be observed with the throttle body removed from the intake, plugged into the harness: Key on engine off after 20 or so seconds the ECU tries to calibrate the throttle body position. The mechanism is dual spring loaded with a second spring that acts to rest the throttle plate around 5-7% at idle. During calibration the ECU will reverse DC to act against the idle stop spring to find out where "0" or fully closed actually is. My impression is Volvo goes a little too far in thinking they can use adaptive strategies to compensate for excessively worn internal throttle body mechanicals when the system just needs to 'give up' and throw a DTC. This may act different on newer ECU software update versions. I'm not sure mine has ever been updated after ~2008 or so.

[precopster]

The main difference between Bosch and Magnetti units is that the Bosch units are reporting directly from the angle sensors to the ECM. Very little to go wrong on Bosch units apart from carbon sweep films and motor....and that very dodgy connector.

Magnetti units take the voltage from the angle sensors and interpret these voltages to the Canbus where throttle angles are reported. There is a power supply built into each throttle and a logic board with varying levels of firmware which does the angle interpretation. In many cases I have seen the films in perfect order yet only one throttle angle is reported correctly. The failing side is reported as 108 degrees. They also report absolute throttle angle through one of the wires to the ECM but if you have old software the car will go into limp.

The whole board on the Magnetti uses aluminum wedge bonds for connection between components. XeModex have found the weakness in these bonds and replaced the aluminium with copper wedge bonds. There are also a number of components on the board that can fail causing only one sensor to read (hence the 108 degree angle on only one sensor)

Another issue I found is that the round magnet has a layer of loose iron filings over which is an aluminium cover which can deform causing it to have "lumps" causing a short to the armature and blowing the 10A fuse for the throttle. The fix involves rolling the magnet like a rolling pin on a hard surface until it assumes a round shape.

On each end of the magnet are D shafts for the small sweepers. Magnetti designed one end of the shaft to be screwed on and held in place by Loctite. On some magnets there is a 10 degree variance because not enough Loctite was used to hold the sweepers at consistent and parallel angles to each other.

Under the circuit board is a stainless steel cover which is supposed to be smeared with conductive paste to help the board cool. I have seen many examples of little to no conductive paste being used causing premature failure.

Another major issue is that if you don't have updated software (post 2006) your car will go into limp mode on detection of only one sensor or a minor voltage fluctuation on the logic board and be mostly undrivable. I've advised more than one customer to get updated software INSTEAD of replacing the throttle IF both sensors are reporting and this has worked with great success.

Interestingly Lamborghini use EXACTLY the same throttles as Volvo for their Gallado and Murcielago range in the early 2000s. I recently converted two low mileage Murcielago units to contactless for a very insistent customer who had no diagnostic equipment and a "theory" that the films were the cause of his Lamborghini blues.

[xHeart]

Thank you for sharing.
I now have VIDA2014D fully working. Using Freeze Frame is indeed a useful data set.

Reference: FUEL SYSTEM - Electronic Throttle System Troubleshooting:

"There will be a patch for VIDA from which point mileage (Km) will be included in the
ECM freeze frame data. This will allow a very quick comparison with the odometer to
determine if the fault has occurred as part of your fault tracing and should be ignored. E.g.
CAN network related codes can be set because the battery has run down while working
on the vehicle, with interior lights and other loads draining the battery.
The freeze frame will give the distance in Km. Multiplying this value by 0.62 you will get
the mileage. On a vehicle with a DIM (Driver Information Module) the distance can be
read from the DIM in Km for an easier comparison."

I do not see this parameter "point mileage" in our version of VIDA2014D.

[xHeart]

ETM profile:

MVS_VIDAETM_2910.jpg (338.23 KiB) Viewed 13752 times

[precopster]

That's the latest software, xHeart. Your car won't go into limp mode. Also if you need to purchase a new throttle you can go for Volvo part number 36050563 and usually (95% chance) it will have this version of software pre-installed.

You'll notice on the report that your hardware number is actually 8644347 so is amongst the affected numbers; no-Magnetti product is exempt here.

Look in Communication-ETM- Throttle angle sensor 1 and throttle angle sensor 2 to see reported angles.
Also you can do ETM sweep test in Communication-ETM-Advanced

Also IPD are doing heavily discounted XeModex throttles at the moment however these are virgin and left blank with no software. Sergey or Henry can help there if needed now that you know your Network numbers for the throttle.

[xHeart]

That's the latest software, xHeart. Your car won't go into limp mode. Also if you need to purchase a new throttle you can go for Volvo part number 36050563 and usually (95% chance) it will have this version of software pre-installed.

You'll notice on the report that your hardware number is actually 8644347 so is amongst the affected numbers; no-Magnetti product is exempt here.

Also IPD are doing heavily discounted XeModex throttles at the moment however these are virgin and left blank with no software. Sergey or Henry can help there if needed now that you know your Network numbers for the throttle.

I can go either way Volvo OR ExMODex, what is best?
The currently installed yellow label has 46+K miles on it. Is the hardware #8644347 specific to yellow label installed at inlet manifold OR a relative id# for this vehicle/VIN?

Would the original white label on my shelf an acceptable unit for XeMODeX "Repair and Return"?
https://xemodex.com/us/product/electron ... 821-10-20/