RESOLVED - Ignition not switching off

Hi all, I think I have an issue with my ECU, but would love second and third opinions from brains much more experienced than mine.

Today the old girl had a nearly flat battery and a live ignition, even with no key in the ignition. She started fine when jumped and ran fine as well.

When looking through wiring I can't see any apartment issues and the ignition lights will only go out if I remove fuse 12 (engine management feed).

Can't see any oil in ECU lead.

Is it an issue with my ECU or could it be a short?

Just reading through other posts. Could oil in the harness side cause the issue, even if there is no visible oil at the ECU end?

Faulty ignition switch?

Tested that. All tested ok

I don’t know.
but if you have the diagrams where/how is this fuse 12 getting its power?
Is there a ”stuck” relay in there maybe?

But I can’t see how it can be the ecu, it’s doing what is asked of it if it’s given power, is it not?

J

Hey marjon,

Yeah, starting to get pointers to check relays and the related circuit over the ECU itself. Which is reassuring tbh.

Something dawned on me this morning, I fixed a sidelight on Saturday that needed re-wiring. I didn't have time to test the circuit and simply went as far as 'Does touching tis wire to this wire make it work!?' At the same time, I also noticed that my spot lights on the bumper stopped working and the light bar was flickering, at the time I put those down to something for the list to fix later.

Reckon I've gone and introduced a perm live feed into the circuit

So, I'm hoping this is a user-error moment, will find out later...

Progress update... Discovered that the live feed is broken by switching on either indicator, so I was assuming there's a bad earth somewhere in the lighting circuit, but noticed when I pulled the key out that I didn't hear the usual click from the igntion switch. Could that be the issue??

May fit a new one as a precaution as I have all the dash out anyway at the moment.

rotterM said:

Hi all, I think I have an issue with my ECU, but would love second and third opinions from brains much more experienced than mine.

Today the old girl had a nearly flat battery and a live ignition, even with no key in the ignition. She started fine when jumped and ran fine as well.

When looking through wiring I can't see any apartment issues and the ignition lights will only go out if I remove fuse 12 (engine management feed).

Can't see any oil in ECU lead.

Is it an issue with my ECU or could it be a short?

Click to expand...

Hi. I can't understand too much from your description, first of all what do you mean by "live ignition"? also which "ignition lights" are going out when you remove F12 (i presume engine bay) which is not for engine management but for autobox ECU...or is it about a Defender??... better explain clearely what vehicle it is and what's going on without making presumptions if you dont know exactly what you are doing then maybe i can help

Not sure why I liked it but it gets your attention .

First I would say, undo the wiring you did for the sidelight, then check all your earths.
then go from there. Of course we are all assuming it did run ok before

Oh listen to this guy too^^^^ .

J

By live ignition I mean that the engine does not switch off when the ignition is moved to the off position and the key is removed all together.

The latest today (as above) is that the engine WILL switch off but only if the indicator is used (left or right) or the hazards are switched on. That cuts out the fuel pump and shuts the vehicle down (as you'd expect by normally just turning the vehicle off).

rotterM said:

By live ignition I mean that the engine does not switch off when the ignition is moved to the off position and the key is removed all together.

The latest today (as above) is that the engine WILL switch off but only if the indicator is used (left or right) or the hazards are switched on. That cuts out the fuel pump and shuts the vehicle down (as you'd expect by normally just turning the vehicle off).

Click to expand...

This seems very like an earth issue

So, been quiet for a bit, but felt it may be relevant for somebody else to say that the issue is fixed and what I did.

Lighting I previously mentioned was fine. In short (excuse the pun!!) My issue seemed to be mainly around rubbish wiring thanks to previous custodian of the defender as well as I suspect a dodgy coil relay.

I stripped out and decommissioned a load of lighting, winch cabling, CB, secondary aux battery (that simply wasn't needed in the set up) and installed a new commercial battery and coil relay as well as cleaning up a load of connections and re-soldered the scary looking cables that were needed.

All working fine.

So yeah, another earth fault/broken relay.

Good work sorting it out.