W203 2.2 cdi t model 150hp 2007 722.699 Automatic 5 speed transmission with sport mode

[Liam Stewart]

Hello everyone, I have a RHD 2007 c class estate, 220cdi 150hp, with the 5 speed 722.699 automatic transmission. It has sport, cruise and manual driving modes.
Abs front right signal was faulty abs light on, so replaced sensor ring, badly corroded backing plate and abs sensor.
Had historic rear left Abs sensor code also
Replaced disk backing plate and cleaned on front left also.
Abs signals now good, warning lights gone/ cleared

engine management light on
No limp mode. Car drives but on an up gradient it goes through the gears quickly with a lack of revs and power.
I have reset the transmission and removed the fault with the icarsoft reader

Tried switching to sport mode,
Have had intermittent results, works briefly then engine management light comes on again with a lack of power in gears and going up the gears too quick. I can use the paddles to go down and up the box to make do.
I’ve renewed the transmission control unit
Resistance checked the solenoids (varied between 2.5 and 7 ohms).
Changed the transmission oil filter and renewed the oil, (it was dirty but still a bit pink).

test drove after clearing the EM warning light and resetting transmission again.
Same problem but drove a bit better especially on level or downhill. Drove 5 miles Switched to sport mode, got really good power but immediately Engine management light came on and sport mode deactivated. Back to the same problem.
I’m thinking it’s something at the transmission control module and I want to check the solenoids again without dismantling.
Do you know where the TCM is on the car please and any help with electrical fault finding is greatly appreciated.
Regards
Liam Stewart, Fife, Scotland

 

[arthur_clark]

quote "I’ve renewed the transmission control unit" ????

 

[Liam Stewart]

Hello thanks for your reply, I renewed the unit which sits above the valve block, oil, oil filter, plug housing. I did this as I couldn’t get an n3 speed sensor reading.
So I’m looking for the module that controls the unit if you know what I mean thanks

 

[arthur_clark]

the TCM on my c200 is under the carpet on passenger side getting mine replaced at merc at a cost of £722.40 new TCM and codeded to the car

 

[arthur_clark]

Hello thanks for your reply, I renewed the unit which sits above the valve block, oil, oil filter, plug housing. I did this as I couldn’t get an n3 speed sensor reading.
So I’m looking for the module that controls the unit if you know what I mean thanks

thats the electro or conductor plate, did you do the bushing at the same time about £10

 

[Liam Stewart]

Thanks Arthur that sounds pretty bad. What was wrong with it? I think im going to check voltages and resistances and if I hear solenoids going.

 

[Liam Stewart]

thats the electro or conductor plate, did you do the bushing at the same time about £10

What’s the bushing? If I have to I’ll go back in there

 

[arthur_clark]

Thanks Arthur that sounds pretty bad. What was wrong with it? I think im going to check voltages and resistances and if I hear solenoids going.

limp mode stuck in secound, no gears no sport or comfort mode no paddles

 

[arthur_clark]

What’s the bushing? If I have to I’ll go back in there

the round connector for the wire's on the conductor plate

 

[Liam Stewart]

I did change the plug housing which is referred to as plug bushing on a youtube video.

 

[Liam Stewart]

Yes that’s it, no leaks so far.

 

[Liam Stewart]

I have a manual for the 722.6 gearbox which I got online. It would be good to find one which is upgraded to cover sport mode. I believe mine is 722.699.

 

[Liam Stewart]

Hopefully on the attached file the identifier for the connections is the right one. Cheers

 

[Liam Stewart]

Found the TCM it was behind a metal plate at the footwell of the Front passenger side.

I cleared the engine management light yesterday,

With the power off
I did a resistance check with the meter.
POS lead to pin 38 (system voltage) then..
1.Neg lead to pin 37 shift pressure control solenoid ground signal = 5.4 ohms.
2.Neg lead to pin 36 Modulation Pressure Control Solenoid ground signal = 5.4 ohms.
3.Neg lead to pins 14,15,16 which are all the shift control solenoid ground signals and all were = 4.6 ohms

I then switched to Volts, put the negative lead into pin 30 which is TCM ground and turned the ignition on to the second click.
I put the red lead to pin 29 TCM supply = 11.89v
Then to pin 38 battery /system voltage to all solenoids = 11.99v
Then to pin 13 which is sensor supply voltage (5v) = 6.04v
Then pin 36 modulation pressure control solenoid ground signal = 7v
Then pin 37 shift pressure control solenoid ground signal = 5.72v.
it seems fine to me.
I have not attempted to activate the solenoids individually.
so I’ve put it back together for now.

 

[arthur_clark]

geabox oil level is crucial check again after running

 

[Liam Stewart]

My icarsoft mb v1.0 lists the transmission modes as c=winter, s=standard and m = manual
I thought they were c = cruise, s = sport and m= manual.

 

[arthur_clark]

My icarsoft mb v1.0 lists the transmission modes as c=winter, s=standard and m = manual
I thought they were c = cruise, s = sport and m= manual.

me to, where did you get your reader from i want one although my £3 reader of ebay brought up the same code's as the star reader at the garage

 

[Liam Stewart]

I got the icarsoft mb v 1 on their website. In retrospect I probably should have bought the v2. Or splashed out on their multiple vehicle version.
This clears codes well
Clears warning lamps well also.
It seems to take a while to read codes when a warning lamp appears.
There’s a lot of real time readings from the cars modules. From it I confirmed the front right abs rpm signal as deficient and the n3 speed sensor as deficient.

 

[Liam Stewart]

Tonight I had a look at the rear abs sensors as the abs light came on again the other evening. I tried getting a resistance value at the cable connections., was unsuccessful on both as possibly the meter is faulty or my method. I put it back together and checked running cold transmission, it was low. I’d filled it up with 3.5 litres. I topped up to 4litres then went for a drive. Still a lack of power Shifting too quickly less than 3000 revs. Speeding up on the flat and downhill.
Checked the oil level Vehicle stationary, hot, running. After being stationary but Running for 10 mins more it was 10mm low on the dipstick. Thanks for the oil tip. Hopefully it’s the simple stuff that will matter in this case.,

 

[Liam Stewart]

No warning lights this time so far