P0705 code and I am completely frustrated!

[guyszoo]

Here in Alabama we have been in a severe drought until a week ago and I'm guessing this has something to do with my issue. Drove the car to work with no problems and when I tried to crank the car to go home it wouldn't start. All lights work fine. Battery is 2 months old. Finally cranked but stuck in limp mode. Wont go back to Park until I turn it off in Neutral. Then gear shifter moves fine. iCarsoft MBII shows code P0705 (Transmission Range Sensor) but dealer tells me this car doesn't have one. I pulled the Floor Shifter Module, disassembled it, cleaned every pin and board with electrical contact cleaner and canned air, and reassembled it. Car cranked and ran normally for about an hour and then wouldn't crank. I have cleared everything I can possibly clear (including ABS light that was on before I bought it last year). Vehicle showed no codes right before it wouldn't crank this last time. I suspect the Brake Light Sensor but can't find it. It's not at the top of the brake pedal. I've read it doesn't have one but uses a Brake Pressure Sensor. Does anyone know if the sensors on the master cylinder can give the same troubles that a brake light sensor can? Tired of borrowing a vehicle. Please someone help.

 

[whitenemesis]

You're guessing, get the codes read using STAR.

BTW, just curious but why do you think the drought breaking has anything to do with your problem?

 

[BlackC55]

What does the gear display tell you on the cluster? Is it blank?

 

[guyszoo]

Moisture and electronics don't jive. I've found two other threads discussing my problem exactly but in both cases the brake light switch was the culprit. If my car has one I don't know where it is. It's definitely not where most on a Benz are. Thank you for replying.

 

[guyszoo]

When it drives normally the position indicator is correct but when it is in limp mode it shows that it is in reverse. Thank you for replying.

 

[jon.english68]

can you read the live data,

the 722.6 has a neutral switch inside the transmission too,

its on the top of the valve body and is part of the electrical plate,

they are very troublesome, the neutral switch is in the oil temp circuit,

if you can read the live date, check the oil temp, the oil circuit should be open in Park and Neutral, and give a temp reading in all other gear position.

 

[pnevesfoto]

hi,
I had the same problems you are experiencing now...
are you sure that your PRND selector module is working fine?
mine appeared to do so, and was not!
several times I disconected the plug and it was back operational again, but in the end, I had to replace the module...
please get your codes read by a STAR software... it often is more than it looks like...
and it can be cheaper and simpler to...!

 

[rorf]

Gear selector module problems can be due to liquids having been spilt in that area.