Intermittent electrical issues E85 3.0si

[Will_4555]

Hi all,

Firstly just want to say hi, new member here (although I’ve owned my E85 for 6 years now), and this forum has always been a useful source of info for me

My E85 has now developed an electrical fault I’m not sure where to start with though. I’m pretty practical with a spanner but not the best electrically, so after some guidance please if anyone has experienced similar issues to the ones below?

The issue is intermittent, and seems to occur to varying degrees every other drive.

Faults usually include:
- Airbag light on
- No parking sensors (solid beep when selecting reverse)
- No indicators

As of today they’ve also included:
- Engine not starting (took 5 attempts to crank)
- No A/C
- Boot button not functioning
- Constant wiping when auto wipers position selected
- Instrument back light not on
- Roof not functioning

The faults seem to always appear when first starting the car, and usually disappear while driving. Sometimes after 30 seconds, sometimes after 20 mins. It does appear to be getting worse though

My car is an E85 3.0si currently on 160k miles
I have got Carly to help with diagnostics

Appreciate everyone’s help

Cheers Will

 

[bigwinn]

Hey will

Having experienced electrical issues with my recent project which is also a 3.0si I can empathise with your frustrations.

My experience was a loose earth- let me have a look at the wiring diagrams to see if there is commonality with those components you name at all

Any signs of wiring damage from rodents at all?

Stuart

 

[markplant]

I'll go with the obvious,
How old is the battery
Has been allowed to totally flat recently
E85 is susceptible to poor battery voltage

 

[Will_4555]

Thanks Stuart

Nothing I can see that’s obviously damaged anywhere. I haven’t started removing any trim/dash to look deeper though

The car is used daily so never really stood for long to let rodents in

A few months ago the cooling fan packed up which I replaced with a second hand one to fix that. These issues seemed to coincide with that, although I’d just assumed it a coincidence rather than connected

 

[Jas- USA]

As of today they’ve also included:
- Engine not starting (took 5 attempts to crank)
- No A/C
- Boot button not functioning
- Constant wiping when auto wipers position selected
- Instrument back light not on
- Roof not functioning


Battery or ignition switch, either has been known to trigger these issues.

However, your earlier electrical issues might have another cause.

 

[bigwinn]

looking at the wiring (and from my experience see thread here: https://z4-forum.com/forum/viewtopic.php?t=147080 )

A lot of the things you mention route via earth points around the drivers footwell (assuming its RHD)- wipers, indicators, boot switch, roof)

I would pop the panel off where the speaker sits in the footwell and have a check of the brown wiring earth points

I'd also be checking the fuses and operations- to see if any of the other issues are red herrings- example is your rear parking sensors making that noise mean one or more of the sensors has possibly failed.