W210 E280 in limp mode but code wont clear after repair?

[MilesMurphy]

Hi Guys,

I recently bought a W210 2002 E280 with a gearbox issue.

-Car was in limp mode, only 2nd and reverse could be selected.
-When I plugged my scanner I received to codes
P0730 = Incorrect gear ratio
P0715 = Input/turbine shaft speed sensor 'A' circuit
-After changing the conductor plate and the 13 pin coupler (both new), refilling the fluid, the 2 errors cleared although another came up. At this point the car was still in limp mode.
P2066 = Fault stored in component 'N15/3 (Electronic Transmission Control (ETC/EGS) module)'. (P0715)
- At that point and from what I had read the current and stored code needed to be cleared in order to take the car out of limp mode. So I purchased a iCarsoft MB V1.0 as it said it can clear these problems via the 38 pin connector (purchased that too, not the cheap one either).
-Tried to clear but the code doesn't want to clear.
- I then checked the tcu for oil which there was non, cleaned the connectors with electric contact cleaner, blew away the crap and reinstalled it.
- checked and clean the plug to the conductor plate, which when I first did the job was covered in oil. So today I went in an clean that with contact cleaner and blew that out.
-ran the checks but still the P2066 fault code it still there and it still wont clear.

Has anyone had this issue?
Is the iCarsoft scanner able to do the clear?
Is the TCM bad?

 

[MilesMurphy]

Any help would be appreciated

 

[Steve@Avantgarde]

It's a W210 and from memory you have to use the 38 pin diag plug.

It could also be you have mis-diagnosed your fault. For example P0730 and P0714 are fairly generic fault codes brought on by gearbox limp mode, eg, if you loose comms with the gearbox ECU then it wont talk to the plate and bring up those 2 codes.

I'd suggest seeking the help of an independent.

 

[MilesMurphy]

Hi,

The 2 codes cleared after replacing the old conductor plate and pin connector. And I was left with
P2066 = Fault stored in component 'N15/3 (Electronic Transmission Control (ETC/EGS) module)'. (P0715)
Which is not clearing. I wasn't sure if its iCarsoft v1.0 not being able to clear the fault. No other faults have appeared whilst scanning the car, just that.

 

[LostKiwi]

Have you checked for oil in the transmission ECU? It wicks along the loom and contaminates the ECU.

 

[ajlsl600]

Yes aware of that on my w208 and ultimatlycwhyvitcgot moved on., what a crock of shxte design! Not rocket science to avoid. Modern electronics, seems benz can't, won't sort that out,at build level, makes it out of warranty so p off seems to be the deal.

 

[Uncle Benz]

The P2066 code is stored in the engine management ecu. It will not automatically clear just because you have resolved and cleared the transmission faults in the TCU. You’ll need to go into the engine ecu and clear the fault there

 

[MilesMurphy]

Have you checked for oil in the transmission ECU? It wicks along the loom and contaminates the ECU.

Yes checked in the tcu, was clean. I will say when I removed the plug that connects from the loom to the 13 pin connector on the transmission that plug was covered in oil, how long it had been there, I don't know. I clean it with contact cleaner and blow it out with air. It could still have a ton of oil up the line.
But I suspect my icarsoft probably can't clear the code and I've been sold a bit of useless kit. Only way to know is to hand it to a merc specialist. If they clear the code, then I know iCarsoft is crap andit goes back for a refund.

 

[MilesMurphy]

The P2066 code is stored in the engine management ecu. It will not automatically clear just because you have resolved and cleared the transmission faults in the TCU. You’ll need to go into the engine ecu and clear the fault there

Tried that with icarsoft v1.0 but when I delete the code then immediately go in to fault codes, it's there, like it never cleared

 

[Uncle Benz]

I think you might need the services of someone with a better diagnostic machine

I’ve never seen the 38 pin to 16 pin adapter cables work properly

 

[Uncle Benz]

You don’t have one of these strange cars that has the 38 pin under the bonnet AND a 16 pin in the driver’s footwell??

 

[MilesMurphy]

Yes it has both, the kit I bought said the 38pin adapter has 2way communication chip in it to allow this clear codes and other bits.

 

[Uncle Benz]

You might find the engine can only be reset via the 16 pin socket

These cars with both sockets are a funny fish. From memory only the ABS and the engine are on the 16 pin socket, everything else is on the 38 pin

 

[MilesMurphy]

You might find the engine can only be reset via the 16 pin socket

These cars with both sockets are a funny fish. From memory only the ABS and the engine are on the 16 pin socket, everything else is on the 38 pin

OK, I'll give that a try tonight.

 

[MilesMurphy]

Quick update

Tcm was at fault after running ohm and voltage tests.
Pin 30 to 38 >to conductor plate should have between
11v to 14v

The tcm was reading 3.4v
The replacement tcm read 3.8v
So I took I working one from a working car at that showed 11v. Was able to select gears initially as it technically was the wrong tcm for the car. But going from D to R didn't have harsh engagement.

Just need another tcm but the one I ordered was also faulty. Looking for one like this.
Thanks

 

[rich.g.williams]

Quick update

Tcm was at fault after running ohm and voltage tests.
Pin 30 to 38 >to conductor plate should have between
11v to 14v

The tcm was reading 3.4v
The replacement tcm read 3.8v
So I took I working one from a working car at that showed 11v. Was able to select gears initially as it technically was the wrong tcm for the car. But going from D to R didn't have harsh engagement.

Yes your TCU would have bricked itself if there was a wiring/solenoid problem (see my post on your other thread).

TCM Numbers explained thread

Pin 29 on TCU is Battery positive into TCU, Pin 38 is Battery positive (switched by TCU) out to solenoids, Pin 30 is Battery negative into TCU, Pin 33 is Battery negative out to the speed sensors n2 and n3 and to s1 b1 (not switched).

Pin 38 is switched Common Battery Positive out from TCU to all six solenoids. So to turn say solenoid y1 on the TCU pulls pin 36 to ground (Battery negative). TCU checks that solenoids are not open circuit or short circuit.

Yes you were reading 3.4V between Pin 30 and Pin 38 because the TCU has bricked itself and as soon as it bricks itself it turns the Battery positive to the solenoids off - so no solenoids can operate (failsafe limp home stuck in 2nd gear mode).

The wrong TCU for your car may not brick itself but it will also turn the Battery positive to the solenoids off (failsafe limp home stuck in 2nd gear mode) while its in your car.

All solenoids must be connected and working (measure continuity and ohms) before powering up any TCU or TCU will brick itself. Also the conductor plate, speed sensors n2 n2 reed switch s1 and temp thermistor b1 all must be good before powering up any new TCU or (yes you guessed it) it will brick itself.

All this bricking business is a pain, but I think done for safety reasons, so as soon as TCU detects something it does not like all transmission electrics goes dead, if car is moving it stays in current gear (eg 4th gear say - solenoids all off cannot change gear) but after stopping and restarting the transmission is stuck in 2nd gear this is a hydraulic valve default setup - all solenoids off transmission hydraulic valves default to 2nd gear, working pressure is maximum and car takes off with a bump.

"Just need another tcm but the one I ordered was also faulty. Looking for one like this" not faulty just bricked itself - see my post on your other thread, as mentioned these TCU's don't become hardware faulty (they are very well built and reliable) its just that they brick themselves.

When it bricks itself the TCU writes (by itself) to its own flash memory that a fatal non recoverable fault condition has occurred and programs itself functionally off, only coding/firmware mod can fix this.

Good luck

 

[rich.g.williams]

Yes checked in the tcu, was clean. I will say when I removed the plug that connects from the loom to the 13 pin connector on the transmission that plug was covered in oil, how long it had been there, I don't know. I clean it with contact cleaner and blow it out with air. It could still have a ton of oil up the line.
But I suspect my icarsoft probably can't clear the code and I've been sold a bit of useless kit. Only way to know is to hand it to a merc specialist. If they clear the code, then I know iCarsoft is crap andit goes back for a refund.

ATF fluid in the plug is no problem - resistance of ATF is high whereas resistance of solenoids is very low (few Ohms). Worth remembering that the entire Conductor Plate and all its brass conductor tracks are immersed in ATF.

Even if the ATF pipes all the way inside the TCU still does not cause a problem, that said if there's enough ATF inside the TCU it could possibly cause a problem by affecting some of the higher resistance circuitry - for example by stopping the crystal oscillator oscillating something like that, could even argue that a bit of ATF inside the TCU might do some good by stopping water getting in! Water is very good at stopping and corroding electronics. Mercedes must be pretty confident about the TCU because the PCB is not even varnished.

It could be argued that ATF could cause a bad contact (open circuit) in the Pilot Bush or the TCU connector but seems unlikely, what's also possible is that a solenoid is not bolted down fully or there is a broken track on the Conductor Plate or a solenoid winding is open circuit.

 

[rich.g.williams]

The P2066 code is stored in the engine management ecu. It will not automatically clear just because you have resolved and cleared the transmission faults in the TCU. You’ll need to go into the engine ecu and clear the fault there

Clearing the generic ECU code is easy but what's more difficult is to clear the TCU code in the TCU, if this is not cleared the ECU will likely come back.

 

[MilesMurphy]

Ah I see,

I replaced the conductor plate with a new one.
I'll recheck the resistance of the solenoids again. I did write the figures down and I'm sure they were in tolerance. It maybe that I got the other tcm that had bricked itself prior to me fitting it.
Just to confirm I bought the car with this issue.

STAR TekInfo

Was using this page for testing figures

 

[rich.g.williams]

All the solenoids are lower than ten Ohms each. As long as solenoid is not short circuit or open circuit they are likely to be ok.

There are accurate resistance figures for each solenoid type (six solenoids three types) but they are most likely to be open circuit or ok. A shorted turn in a solenoid would cause problems but hard to test for, If you fitted a new Conductor Plate chances are all is ok electrically now.

It's possible to test the solenoids on the bench but I don't think they ever fail much.