Technical Hello and help me please

[osintseva]

500 2014 manual tis my granddaughters car and I am trying to fix an issue where if the hazard lights button is pushed the hazards come on but also the drivers window will go up if its down, if its up I can hear the motor in the door trying to go.
The hazards don't turn off if they are on and I press the hazard button to toggle off, I have to flick the indicators left and right until the hazards stop.

I have sliced open the rubber boot on the rear hatch loom and cant find any damaged wires, done similar on both doors and those wires look ok even though they are wrapped n tape. I have checked both fuse boxes for water and tested a jump lead from engine to the neg on the battery and also from a suspension leg bolt.



Its driving me nuts. I would be very grateful if anyone has a clue as to what it may be.

Happy Xmas all.

 

[varesecrazy]

Hi
It does sound like an earth fault..

Basic question..
If you unplug the Hazard switch.. Do the indicators alone trigger the window motor?

I have had chafed wires at a door hinge..

Try operation with doors open and shut.. Trying to find if it changes

 

[osintseva]

Ah cheers for the reply

Tried with doors open and shut.

I will unplug hazard switch tomorrow and check if indicators trigger the window.

Do you know if a jump lead is too long to make an earth connection for testing purposes?

 

[varesecrazy]

What's your history with the car..

Had it years with no issues?

Recent purchase?

 

[osintseva]

Hi

Had it for year and a half no issues.

 

[varesecrazy]

No work done, then it may be a worn through cable

Interested what unplugging the hazards does..

 

[John202020]

Two things to try first
Disconnect the battery have a coffee and re connect?
(How old is the battery)?

 

[Matt Quinn]

Basic question..
If you unplug the Hazard switch.. Do the indicators alone trigger the window motor?

That strikes me as a very good question... is there an 'indicator' (i.e. a mirror repeater) in the right hand door? The suggestion of chafed wires - at a door hinge or otherwise associated with the door wiring - strikes me as a very logical one. ...Personally (on different cars and different circumstances) I've fond myself having to scalpel-apart sections of loom - only finding the 'short' under a strong light with a magnifier!

...Nobody's been in there footering about with different speakers or the like, by any chance? - Or otherwise had the door cards or side panels off?

Two things to try first
Disconnect the battery have a coffee and re connect?
(How old is the battery)?

Again, good suggestions... the coffee particularly. - The just plain weird faults that many modern cars throw up when the main battery falls a tiny fraction of a volt below some or other arbitrary value (but is otherwise healthy) is bizarre!

Do you know if a jump lead is too long to make an earth connection for testing purposes?

If it's a half decent, clean lead then it should be fine... you'll find its DC resistance will be negligible. Maybe a bit clumsy in use because of the big croc clamp - but otherwise OK so long as you don't short anything on it.

 

[steveras57]

Even a very minor "short" somewhere (hazard switch for instance!) can play havok with the can- bus system linking things that you would never think could be connected! think the previous ideas of disconnecting the switch and testing along with the door hinge wiring are good places to investigate in depth! best of luck and keep us posted!

 

[osintseva]

hi thank you

I have just tried indicators with doors open and doors closed.

Indicate left appears to do just that and nothing else

Indicate right puts both indicators on and drivers window up or if its up will activate motor, however using windows up switch turns hazards on but not off, window goes up, hazards can be turned off with hazard button.

Ok so to indicate right, indicate right, indicate left and back to right quickly. The hazards come on but go off leaving the right indicator on ok.

Will disconnect battery now, going gym, will update.

Thanks again

 

[osintseva]

I disconnected battery for a good while and the problem's still there.

Have a battery receipt from September 2021 but also a note on a service receipt from December 2020
"ABS lamp flashes when right indicator activated. Possible wiring fault. Further investigation required"
No record of a follow up.

 

[varesecrazy]

I disconnected battery for a good while and the problem's still there.

Have a battery receipt from September 2021 but also a note on a service receipt from December 2020
"ABS lamp flashes when right indicator activated. Possible wiring fault. Further investigation required"
No record of a follow up.

That kind of thing.. Is not uncommon with the 2 door 500

It is due to damp effecting the PCB of the dashboard, NOT likely to drive your window..

 

[osintseva]

If you unplug the Hazard switch.. Do the indicators alone trigger the window motor?

I cant get the hazard button out

These problems are still there with the ignition off does that mean the hazard circuit is powering the windows and right indicator?

 

[steveras57]

For safety the hazard switch is powered direct without the ignition on! so if the window and right indicator work WITHOUT THE IGNITION SWITCHED ON! then its extremely likely that there is a short between the hazard switch and those systems! dont know if the 500l,s suffer with the same tailgate wiring issues as the 2 door 500,s but if they do then thats where id be looking!. even though you say you have looked at the rubber gator area you might have to look more deeply around there before extending your investigations!

 

[osintseva]

Cheers for the reply, I will check tomorrow
It is a 2 door, I may have misdescribed it, its a 500 Lounge

 

[steveras57]

YEP! you said 500L which is the mini people carrier thats what through me!

 

[John202020]

No ones mentioned the BCM? the windows shouldn't work with the key out even if there was a short surely ?

 

[steveras57]

Nobody LIKES! to mention the bcm now do they? reckon Fiat should have called it the body out -of - control module! far more trouble than its worth IMO!

 

[varesecrazy]

No ones mentioned the BCM? the windows shouldn't work with the key out even if there was a short surely ?

Historically..

Windows were constant power,
same as Brake lights and horn

No idea now..

 

[portland_bill]

Being a 500, not a 500L helps, as there's more experience.

The 500, like the Panda, can get water into the BCM. Under the windscreen is a chamber, below the wipers, that has two drains that clog with composting leaves. They need to be cleared at least annually. When the water level gets high in there, it floods into the cabin, onto the BCM.

Might need to take the BCM out and put it in the airing cupboard for a few days.