Hi,

Hoping for some advice.

I have a 2015 CLS 3 litre diesel with keyless entry and the start stop button.

Starting it first thing in the morning, especially if cold it will die immediately after starting and then run perfectly when I start it again. I've noticed that if I remove the start stop button and use the key, turn it to position 2 so can see the glow plug light come on and go off again and then crank the engine a couple of seconds later then it will start normally.

But I hate using my key, I've gotten used to keyless. Is there any way I can replicate key position 2 just using the start stop button?

Any help gratefully recieved.

 

It sounds like the issue with your 2015 CLS is related to the glow plugs not getting enough time to fully warm up when you're using the keyless start. With diesel engines, the glow plugs are crucial, especially in cold weather, to ensure smooth starting.

When you use the key and wait for the glow plug light to go off before cranking the engine, you're giving the plugs enough time to warm up. Unfortunately, the keyless start-stop button might be skipping that warm-up phase since it automatically starts the engine right away.

Here are a few things you could try:

1. Press Start Without Cranking: On some vehicles with keyless start, pressing the start button without pressing the brake pedal can turn on the ignition without cranking the engine. This could replicate key position 2, allowing the glow plugs to warm up. Once the glow plug light goes off, press the brake and start the engine normally.
   
2. Check for Software Update: Some vehicles allow adjustments to the start sequence via software updates. It's worth checking with your dealer or a trusted mechanic if there's an update or option that can allow the glow plugs to activate properly during keyless start.
   
3. Install a Glow Plug Timer: In some cases, installing a glow plug timer module can help ensure that the glow plugs are fully heated before the engine cranks, even with keyless start. This might require some modifications but could be a permanent solution if you don't want to revert to using the key.
   

Since you're keen on sticking with keyless entry and starting, I'd recommend giving option 1 a try first and then consulting with a professional mechanic about potential updates or aftermarket solutions.