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

[MilesMurphy]

Should i recheck the resistance of the solenoids via the loom or directly.
Post either way. Is there anything else that may cause an issue before i plug on a new tcu.

Is it worth plugging the new tcu in a known working car to test if the new device is not bricked?

Many thanks

 

[rich.g.williams]

STAR TekInfo

Was using this page for testing figures

The STAR TekInfo link is interesting, I had not seen that info before, it predates use of 722.6 in my car W203 but still useful stuff on there thanks. Some of the diagnostics tables symptom v suggested cause are a bit OTT wild with heavy focus on ATF level!

 

[rich.g.williams]

Should i recheck the resistance of the solenoids via the loom or directly.
Post either way. Is there anything else that may cause an issue before i plug on a new tcu.

Is it worth plugging the new tcu in a known working car to test if the new device is not bricked?

Suggest you test at location where the TCU is, and looking into unplugged connectors N15/3. Do everything Ignition Off. Suggest you only do these tests from the STAR Tekinfo link you gave as follows:-





Table above gives the pins on N15/3 the last test is two tests one in R/D one in P/N. Suggest you don't try testing the speed sensors or voltages, only above tests. Ignition Off. Here is the N15/3 connectors:-




After testing and everything complete first time you start the car to see if all is OK if all is OK fine, if not Ignition off and go back to looking for fault, also check if any new OBDII fault codes returned.

As regards "plugging the new TCU into a known working car" that's your call.


-

 

[MilesMurphy]

Hi Rich,

Unfortunately I am still waiting for Royal Mail to deliver the part, should have been Friday. So I ran a ohm test again to check the values again and this is what I found.

Test 7 was right at the top for ohm 6Y6 (A140 277 04 35) PWM solenoid. I have, strangely enough, spares, I'll check those and check the resistance, replace.

Test 13 Part 1 was set to 20K ohm. Returned 0.897
Part 2. I couldn't get the value to change from 1. Tried all Ohms settings on the multimeter.

Also like to say a BIG Thank you to Rich .Top-G. Williams for the information about these units. Learnt a lot and saved a lot of time!

 

[Uncle Benz]

I don’t think that part 2 result is necessarily a problem. The 1 usually indicates an open circuit on a digital meter, and that’s a greater resistance than 20k, so seems ok. It’s the starter interlock test, so it’ll only crank in P or N, so if it cranks fine you don’t have a problem imo.

 

[ian lunn]

When I had problems with a transmition conductor I had the faulty one repaired as I was lead to beleave a new unit would need to be programed at main dealer ON THE CAR (this caused a second problem as in I would have to get the car transported to dealer for them to do it), having the origanal repaired ment it did not loose its program, Being in simuler industory for the last 25 year and had to provide all service engineers with expensive equipment to allow electronic control units to be swapped.

 

[alexanderfoti]

I suspect your car works with the replcement TCU as it has no fault codes logged in it, and i don't see that you have succesfully managed to communicate or erase faults codes in the TCU

 

[MilesMurphy]

Hi all,

The tcm has finally arrived. I will test drive it tonight. Initial test with ignition on show good voltage to the required pins. All solenoids reporting good ohm.
I have an icarsoft scanner and icarsoft v1.0 with 38pin adapter from the same place. Unit claims to clear the tcm codes.

 

[MilesMurphy]

Drove the car today.
-Initial startup was OK
-Gear selected without harsh engagement
-Was able to whilst in the drive position to select gears via the trip tripronic selector
-Drove and it change up to 3rd, then stayed there
-Hit the kickdown and after no throttle response
-Shut off and back on. Car limp mode in 3rd. Got back and parked up.
-Scanned and found P2069 fault stored in N15/3 (etc [egs] control unit P0730.

Also another code, which I will change is the throttle sensor but that was a swap with another vehicle as a test, turns out that is faulty, will replace.

The P0730 is the one I interested in coding needed for the tcm to the car?