No Green Ignition Light

[mep]

Hi All.

2006 IS220d SE.  Standard mileage for age.

Completely out of the blue, the most reliable car I have ever owned, fails. No green ignition LED when putting my foot on the clutch pedal.

Due to Covid the car had sat for a while and of course the Battery had almost drained because of the security system.  The battery hadn't drained completely, the key fob still unlocked the doors and talked to the windows.

I trickle charged the Battery over night and ensured with a volt meter that it was sat with around 13v.

Just to be on the safe side I changed both key fob batteries.

I have spoken with my Lexus dealer who ran me through a number of checks.

Battery Voltage.

Fuses (2 lots under the bonnet) & (2 lots in the foot wells).

All fuses check out correctly with the volt meter. 

And still nothing.

Has anyone else experienced this? Heard of another Lexus owner who may not even be on the forum with the same problem?

Getting pretty desperate here.

[scudney]

How old is your Battery?think it should be reading about 14.1 volts.Do you have the Amber light if the press the ignition button?🤔

[mep]

Battery is less than 6 months old and only read what it did because it was very low trickle charge of about 6 hours in total.  

No amber light. No lights at all.

Common sense says a fuse but all fuses test good.  Wonder whether a ignition relay but don't know where to start with that.

[Shahpor]

Hi Martin,

Can I just clarify whether the car is completed dead or not?  In other words, what happens when you try the button?  Does the dash light up or does the engine attempt to crank over?

[mep]

Absolutely dead.  Nothing. Nada.

Key fob flashes red LED when near switch.  Interior lights come on.  Side lights, hazard lights, all work. Press the unlock button on the fob and the windows bleep: though now don't lower. Central locking all works.  Bizarre.

[mep]

No dash lights.

[mep]

From another forum see that Shapor has posted previously about this topic.  I have ordered a replacement Start Button from eBay and going to give it a whirl. But any other comments to look at are most welcome.

 

[Shahpor]

You can test the ignition switch if you are handy with a multi meter:

[mep]

Hi.  I own a multi-meter for continuity testing and a bit of voltage.  Don't understand ohms resistance and all that sorry to say.  Already printed off this document from a previous posting.

[Shahpor]

It is not much different from checking voltage, but fair enough if you are unsure.

Fingers crossed this fixes the issue for you.

[mep]

Don't know as there's much else to try.  According to the fact it's Easter and Covid and, and, and.  It's going to be at least 12 days to get the part and then try it.  I will report back.  If anyone else has any other I dead I can try in the interim period I would still be grateful.

[H3XME]

On 4/4/2021 at 11:52 AM, mep said:

Don't know as there's much else to try.  According to the fact it's Easter and Covid and, and, and.  It's going to be at least 12 days to get the part and then try it.  I will report back.  If anyone else has any other I dead I can try in the interim period I would still be grateful.

Might be related to the sensor when de-pressing the clutch if it doesn't react? There's no other reason as to why it wouldn't start if you say the Battery is good.

[mep]

Hi.  Not aware of a sensor controlling the clutch switch.  Is this different to the switch itself?

[mep]

Hi All again.  I have replaced the Start button.  No change.  I have replaced red the Blue Ignition relay.  No change.  I have noticed that when the drivers door is open, the dash light does not indicate an open door.  I open any other door and the dash red door light open indicator illuminates.  Does the drivers door courtesy light switch do more than just put on the interior lights?

[Shahpor]

That's a shame ☹️

Perhaps you could get an auto electrician around to have a look?  Since it does sound like an electrical fault, hopefully they could give you an idea of where the fault lies if they can't fix it themselves.

[DannyM]

Did you check the clutch switch to see if the pedal is engaging it when pressed to the floor? Would seem the most likely culprit to me either pedal is not engaging it or switch has failed. Mine is very sensitive in my 250, unless the pedal is hard against the floor it won't start.

[mep]

Hi.  Have already removed Clutch switch and tested with a volt meter. Switch works fine.  Normally, without pressing clutch, just press the button, the ignition will come on to allow for radio etcetera.  Pressing clutch pedal 'livens' the ignition for starting the car.  Press the start button and dead.  See las post from me about door switch please.

[mep]

Hi.  have now checked just about every connection possible in this car with a multi-meter.  Clutch switched checked and confirmed okay amongst other things as well.  I have now changed.  Ignition Button, Ignition relay and drivers door courtesy switch.  After a lot of talking I have installed a replacement brand new battery: AND WE HAVE A GREEN LIGHT IGNITION LED. But! Still the car refuses to kick in and turnover let alone start. As yet to try OBD or whatever it's called with a tester.

Any further suggestions are welcome.

[Spacewagon52]

Try disconnecting the Battery for 10 minutes and try again. Nothing much to lose but a few minutes.

[mep]

Okay.  Disconnected the new Battery for 30 minutes and no change.  I think it important to say that even though I now have the green LED, the steering lock does not disengage. I have an acquaintance that is telling me to look at the BIG fuse.  Does anyone know if this is likely to be the cause?  And I ask especially as all other facilities, with the exception of the windows now appears to function.

[Spacewagon52]

8 minutes ago, mep said:

Okay.  Disconnected the new battery for 30 minutes and no change.  I think it important to say that even though I now have the green LED, the steering lock does not disengage. I have an acquaintance that is telling me to look at the BIG fuse.  Does anyone know if this is likely to be the cause?  And I ask especially as all other facilities, with the exception of the windows now appears to function.

Worth a try - sorry it did not work. Battery problems can cause a large range of issues.

[Shahpor]

Hi Martin,

There is something called the AM2 fuse, which might be what your acquaintance was referring to?

It appears to be in the car on the passengers side:

[mep]

Hi Shahpor.  I think i may have misled you by mistake.  The ‘fuse’ being referred to is the long metal looking thing that’s in the box just in front of the Battery. Looking at the lid and the ‘map’ of fuses, point to this ‘fuse’ being a multi-fuse that handles a lot of the main engine components.  Glow plugs, audio, heating items. Martin

[ColinBarber]

Those large fuses don't normally blow unless there is a major issue or user error such as connecting the Battery the wrong way around. It does seem as if it could be the cause such as the main 60A and 80A fusebox fuses or the 150A ALT fuse which feeds many others.

Not sure how easy it is to get to it on the IS. Normally you unbolt the fuse housing so you can get the wiring from underside to test and unbolt the connections to removed the fuse block if you need to replace.

Make you you disconnect the Battery before doing anything with it.

[Lageoddvin]

@mepI had a similar issue to what you describe last summer when my Battery died due to leaving the boot open, and the lamp draining the Battery. When i tried to connect the Battery again, i had all kinds of strange electrical issues. What i did was leave the Battery unhooked over night, then install Battery and leave the car overnight, without touching anything. Did not try to start it, not unlock or lock, nothing. Then in the morning, it seemed the "brain" had snapped back into place, and everything was alright again. Best i could read regarding it was that the brain of the car was stuck, thinking the Battery was faulty, and that disconnecting it for some time, and then connecting it would be the best way forward. Supposedly not that uncommon for a range of cars according to my brothers in-laws.