Bmw engine diagram

If your 2012 BMW 535i is losing all of its water but not overheating, there could be a few possible causes:

1. Leak in the coolant system: The coolant system of your car may have a leak, which is allowing the water to escape. This could be caused by a faulty radiator, a leaking hose or a cracked engine block.
2. Evaporative loss: In some cases, the water may be evaporating due to high temperatures. This is common when driving in hot weather, and it can be caused by a malfunctioning pressure cap or a faulty radiator cap.
3. Leak in the water pump: The water pump may be leaking, causing the water to escape from the coolant system.
4. Leak in the head gasket: A leak in the head gasket can allow coolant to leak into the engine oil, causing the water to disappear.

Check engine light on ? The coolant temp sensor is a input to the PCM - engine computer ! All wires come from an go to the PCM . What type of problem are you having ? Maybe able to save you some aggravation an time chasing gremlins . Coolant gauge not working ?
Engine Coolant Temperature Gage
The instrument panel cluster (IPC) displays the engine coolant temperature as determined by the powertrain control module (PCM) or the engine control module (ECM). The IPC receives a serial data message from the PCM/ECM indicating the engine coolant temperature. The engine coolant temperature gage defaults to 100°F (38°C) if there is a malfunction in the engine coolant temperature sensor or the IPC detects a loss of serial data communication with the PCM/ECM.

But if you insist ,you can find free wiring diagram's here http://www.bbbind.com/free_tsb.html Enter vehicle info. year , make , model an engine ! Under system click on engine ,then under subsystem click on fuel controls . Click the search button then the blue link. The second an third diagrams both show coolant temp sensors . Both go to the PCM .

Coolant is getting into one of the cylinders of engine , head gasket , a crack in the cylinder head or engine block !

It must be loosing coolant if there is white smoke (or steam) out of exhaust, heater will be cold due to lack of coolant, radiator may be full but I suspect engine block will contain no coolant & may have caused an air lock so radiator may still be full, sounds like cylinder head gasket has blown

Hello and welcome to FixYa!

Please do check the coolant reservoir if it sits on the right level. Overfilling the coolant reservoir can cause a coolant overflow when the engine operates on higher temperature. Please do fill it and make sure that it sits on the right level.

Hope you find this helpful and thank you for using FixYa! Have a good one!

Unfortunately, you are experiencing two of the classic signs of a bad head gasket. Have the coolant checked with a test kit from your favorite auto parts store to verify this. I would check the radiator coolant regularly to verify coolant loss. Sometimes engine cooling system designs can allow for a bad hose to come in contact with the exhaust and make smoke out of the tail pipe so have all of the hoses checked too.
Hope this helps.

If your car is loosing coolant, there might be an exterior leak, or an interior leak. First check and make sure that radiator cap is tight and the rubber sealer is intact, there can be many other reasons ...hole in the coolant hose, leaking radiator, heater core, water pump, intake manifold and more... Check and see if there is any puddle of coolant on the ground, if so you can find where the coolant is coming from.
There must be an internal leak, a blown cylinder head gasket. See if the bottom of the oil cap looks like somebody spit on it, if so then coolant mixing with the oil, when the engine is running see if there is any white smoke at tail pipe. If engine overheats, and there are air bubbles in the coolant bottle "boiling", this could indicate a bad cylinder head gasket too.

The engine coolant temp sensor is in the cyl head that tells the computer the engine temp.

Check exhaust, sounds like a small head gasket leak.

sounds like headgasket , when it si done you must make sure you fill with water and no aIR BUBBLES IN SYSTEM .i did one once took me 4 hours with a hose pipe ramming water into it heater matrix first then engine .i had a garage do the gasket 1st time they did not fill with water properly and it blew had to do it myself