First post - 2.5-16 not switching off

[Lugy]

Hi everybody! First post and I'm after help. Basically sometimes my car wont switch off. We know the ignition switch works - switched live parts like electric windows turn off as they should - but the ignition stays live. If I stall the engine then the ignition lights come on as they normally would. The OVP relay and fuel pump relay seem to be fine, they are being activated by something.

Any suggestions?

 

[meanie]

Aftermarket alarm fitted?

 

[television]

I take it the car is a 190 and welcome to the forum

The ignition switch is in 2 parts, the ignition and the accessories,, only by putting a meter over the switch will you know for sure.

I have never heard of such a fault on a petrol engine

 

[Lugy]

Aftermarket alarm fitted?

Nope, the standard alram was turned off when the fob was killed.

 

[Lugy]

I take it the car is a 190 and welcome to the forum

The ignition switch is in 2 parts, the ignition and the accessories,, only by putting a meter over the switch will you know for sure.

I have never heard of such a fault on a petrol engine

It is and cheers.

I like the sound of what you've said, I never knew the ignition switches were in 2 parts. I'll have an investigation when it's light.

 

[jberks]

Back-feed short circuit maybe. A constant circuit feeding back into the ignition one.
Not likely in your case but I had a car that would run without the key if the lights were on and the brake pedal was pressed - Lights back feeding through the bulb to the brake lights then through the switch to the ignition circuit. Wired appropriately even a radio can do it.

Assuming the key switch is ok, I'd start pulling fuses from the constant live side and see when it dies.