My 2003 325I BMW will not crank after driving sometimes. The battery is fine. It seems to be a problem with the Ignition Switch or faulty Transponder. Ater turning the key a couple of time it then will start.

A wiring diagram for your car would be a great help identifying possible fault points and checking the starter circuit with a meter or testlamp.

From your description it would seem there isn't an immobiliser but be aware early transponder keys were identical to ordinary plastic bodied keys.

Firstly ensure the engine will crank by energising the starter manually and then check the ignition/starter switch is doing the job and delivering a starter current into the correct wire. If that is ok the wire is either broken or there is a relay in circuit that is deprived of operating current or is faulty.

Replace starter relay.

I think your mistaken. Your battery will lose cranking power as the temp drops. Warm battery may work just fine, untill it gets below freezing temps then the cranking amps are so low its sluggish. Buy a high cranking amp battery and you will be good as gold mate!

i see dash lights on when you try start engine.could have faulty starter relay or bad starter solenoid or starter bad.use a 12 volts test light see if power going to starter.if starter circuit okay could have theft security problems because BMWS did have theft security key ignition system back in 1994.

Car not starting or turning over indicates towards multiple possibilities. It can be issue with battery or weak battery. But if battery checks out ok, then it can be starter issue or faulty alternator or problem with low fuel pressure or no spark at spark plugs due to dirty spark plugs or faulty ignition coil or injectors getting cracked or dirty and needs to be cleaned.

To confirm the problem, the basic troubleshooting is required.

Click this link below and follow the troubleshooting:------

http://technoanswers.blogspot.in/2012/02/car-starting-issues.html

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This will help.
Thanks.

these cars are known for bad ignition switches

Possible causes: Fuel pump relay, Pump, Fuel Filter, Regulator, Crank Shaft Sensor, Camshaft Sensor, Loos Connection(try to wiggle the wiring harness and observe). or faulty Ignation Switch.

Observe if the engine will lack of power first before to shut off, if this is the scenario it could be a fuel pump relay or pump. I suggest you to monitor the fuel pressure first or try to swap fuel pump relay to other as long as same color or figure and observe it.

If the senario is sudden cut off, it coud be a faulty cranck shaft sensor. a faulty cranck shaft sensor is easy to determine using tachometer while cranking, if the sensor is faulty the tachometer will not move or rise even a little bit if it's good it will rise a bit while cranking the engine.

Check fuel pump when the problem occur, try to ignition ON/Off and listen to fuel pump motor noise from underneath (close to rear right side tire), the pump will operates for aprox 5 sec. everytime you turned ON the ignition switch. and if you can't hear noise then you have to focus to fuel system.

1 Inspect Battery Battery Discharged or Faulty. 2 Inspect Battery Cable Corroded, Broken, Shorted or Poorly Connected Battery Cable. 3 Inspect Fuel Filter Clogged or Dirty Fuel Filter. 3 Inspect Distributor Cap Distributor Cap Cracked or Burned. 5 Inspect Coil - Ignition Faulty Ignition Coil. 6 Inspect Wireset Worn, Damaged or Faulty Spark Plug Wire(s). 7 Inspect Spark Plug Incorrectly Gapped or Fouled Spark Plug(s). 8 Inspect Starter Starter Motor Faulty. 9 Inspect Fuel Pump Low Fuel Pressure. 10 Inspect Solenoid Switch Faulty Starter Solenoid Switch. 11 Inspect Relay - Fuel Pumpat Faulty Fuel Pump Relay. 12 Inspect Fuel Injector Pressure Regulator Faulty Fuel Injector Pressure Regulator. 13 Inspect Ignition Switch Improperly Connected or Faulty Ignition Switch. 14 Inspect Starter Drive Faulty Starter Drive. 15 Inspect Fuel Injector Dirty or Worn Fuel Injectors. 16 Inspect Fuel Pump Strainer Clogged or Dirty Fuel Pump Strainerat. 17 Inspect Engine Control Computer Incorrect Operating Information Being Delivered and Sent From The EEC. 18 Inspect Fuel Tank Fuel Tank Empty. 19 Inspect Carburetor Carburetor Flooded or Faulty Choke. 20 Inspect Distributor Worn, Loose, or Incorrectly Installed Distributor.

BMW CUTS OUT

A few things to check.

1. Is fuel pump delivering enough fuel.
2. Is injectors clean. Perhaps dirt in fuel. replace fuel filter
3. Air leakage at top air intake of manifold at ICV idle control valve. Two hoses inside this housing prone to perishing.
4. Throttle position sensor faulty.
5. Mass air flow sensor faulty.
6. ICV faulty or dirty. comon fault on older e36.

Havent done it yet but ICV is easy to clean according to internet. instruction available at bmw e36 blog. All off above can be tested by yourself according to manual.

Q1. Engine will not start or is hard to start (Cranks OK) A1 -Ignition lock switch faulty -Ignition coil faulty -Power transistor faulty -Spark plugs faulty -Ignition wiring disconnected or broken -Spark plugs faulty Q2, Engine will not crank A2. Battery discharged Battery cables loose, corroded or worn out Transaxle range switch faulty (Vehicle with automatic transaxle only) Fusible link blown Starter motor faulty Ignition switch faulty Ignition lock switch faulty REMEDY Charge or replace battery Repair or replace cables Adjust or replace switch Replace fusible link Repair starter motor Replace ignition switch Replace ignition lock switch