What does fault code c115 in bmw 318 2008 model

Look here for the BMW fault codes - https://www.carpdfmanual.com/bmw/bmw-diagnostic-trouble-codes/ 163 BMW PDF Manuals Download for Free

BMW has been using electronically controlled automatic transmissions in most models since the late '80s. These transmission systems employ a transmission control unit which controls electrical solenoids to manipulate the various control and shift valves and functions in the transmission valve-body. When the transmission control unit detects a problem that it "thinks" could be damaging to the transmission or engine, it goes into a fail-safe or "limp" mode. In this mode, the transmission will function in reverse normally, but in forward it will operate in only one gear (whether you have the shifter in D, or any of the lower gears). This will typically be 3rd or 4th gear, depending on the model. It will start in this gear and stay in this gear with no shifting. You would experience this as sluggish acceleration and higher than normal engine speed at about 40-mph and above.
If you must drive the vehicle when the transmission is in the fail-safe mode, accelerate gently and keep the road speed lower than full highway speed.
Earlier models do not employ fault codes and must be diagnosed manually. Late models do employ fault codes and a diagnostic/scan machine can be used to check and read the faults to assist in diagnostics. Note that this is not your common OBD-II engine management fault code tool. This is what A BMW dealer or a properly equipped independent shop would have for full vehicle system diagnostics and coding operations.

Have the codes read (oBD!!) I would suspect over voltage. This over voltage plays havoc with car systems and show many times on bmw as idrive screen faults and freezes. If codes read over voltage, replace alternator. Don't just replace regulator, not worth the hassle, regulator is attached to alternaor, get a refurb unit, bmw prices are silly.

Fault codes is ? Motor Part Store Motor Parts Wholesale

have you tried having the fault codes reading section of the book
It is the first line of the trouble shooting
it appears that there is an electronic part break down for over heating
it could be in the ignition control module, ECM, coil/s, immobilizer
try exchanging the ECM with a known good one and fix any faults shown on the code scanner

BMW transmission range sensor position Vehicle Parts ...

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BMW vehicle parts & accessories transmission range sensor position related ... i got a transmission fault warninig my bmw car 545i E60 it is a 2004 E60 bmw car ...location transmission dipstick 1997 bmw 328is if its a manuel transmission it ...

P0705 Transmission Range Sensor TRS Circuit Malfunction

www.obd-codes.com/p0705

Transmission Range Sensor Circuit Malfunction (PRNDL input) ... Later models with the transmission range sensor located in the valve body are a different ball ... What causes the P0705 code on a BMW 740i ('97) ... 2004-2015 OBD-Codes.com.Missing: 545

How to Reset the 2006-2011 BMW Maintenance Light …: http://youtu.be/g4ebeJ3uzw4

BMW has been using electronically controlled automatic transmissions in most models since the late 80s. These transmission systems employ a transmission control unit which controls electrical solenoids to manipulate the various control and shift valves and functions in the transmission valve body. When the transmission control unit detects a problem that it thinks could be damaging to the transmission or engine, it goes into a fail-safe or limp mode. In this mode, the transmission will function in reverse normally, but in forward it will operate in only one gear (whether you have the shifter in D, or any of the lower gears). This will typically be 3rd or 4th gear, depending on the model. It will start in this gear and stay in this gear with no shifting. You would experience this as sluggish acceleration and higher than normal engine speed at about 40 mph and above.

If you must drive the vehicle when the transmission is in the fail safe mode, accelerate gently and keep the road speed lower than full highway speed.

Earlier models do not employ fault codes and must be diagnosed manually. Late models do employ fault codes and a diagnostic/scan machine can be used to check and read the faults to assist in diagnostics. Note that this is not your common OBDII engine management fault code tool. This is what A BMW dealer or a properly equipped independent shop would have for full vehicle system diagnostics and coding operations.

run fault codes and look for injector faults an d pressure problems. check HT leads

The computer has detected a fault in one or more of its systems. The only way you're going to an answer as to what the fault is, you're going to have to have someone attach a scanner or code reader to get any codes that are stored.
Most auto part stores can check late model OBD II for free. One may do earlier European.