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Dodgy electrical faults / failing to start - ignition switch

arry

Well-known member
Joined
2 May 2015
Messages
974
Hi :thumbs:

First bit of unreliability in the year I've owned the car - but hopefully an easy fix. Advice please.

Essentially, I've been having moments where the dash lights would go dimmer than usual and when you start the car you can end up with some random lights still on; brake warning light seemingly the favourite, but I've also had a flashing red light at the end of the temperature gauge when it'd only run a min or so.

Anyway, the car failed to start entirely a few nights ago and there's some new symptoms, some of them are rather random :lol:

The dash lights are still flickering / dimming on their own
Hitting the brake pedal kills all power to the dash, including the petrol gauge which hits the deck instantly
Car won't turn over, not even a click from the starter solenoid
Spoiler raised, won't retract


Am I right in thinking this is going to be the electrical portion of the barrel and switch arrangement?

Cheers :)

arry
 
Check that the earth strap from the battery is secure.
 
Do as above first as a raised spoiler is an indicator of a battery supply problem .. then check battery is ok.

couple of other idears after eliminateing battery problems would be a possible leak o/s/f above the footwell that has got water onto the relay board.

Some sort of water ingress to alarm cu under n/s/f seat although wrong sypmtoms for this really.

Ign switch failure is possible but not the symptoms i would expect from that.

Battery fault is most obvious atm though.
 
Sorry for delay in reply, around the time of this all kicking off I managed to separate my lower rib so I've been pretty much laid up a couple of weeks.

Got round to looking over the car yesterday. I'd stuck the battery on my Optimate 4 and left it a week - stuck key in and she fired right up no issues. So, it would appear you were right and it is indeed battery related. A good look around the cabin revealed no nasty water leaks or staining to the relays so I'm hoping that's OK. Earth looks secure from the battery.

I'd ordered a new switch anyway so I'll keep that as spare for another time. I've also ordered a new battery to see how that goes - if that drains down quickly or gives me problems in the coming weeks I'll go looking for any obvious electrical problems.

Thanks for your help.
 
UPDATE:

So after a good few months with no issues on the new battery, this problem has reared its ugly head again :damn:

Ironically, I'd had this intermittent ABS light issue which I'd been investigating and noticed that people had reported similar problems being linked to voltage / charging / battery issues - not me I thought, since new battery and not had any issues since.

But then last week wifey stalled the car pulling into the garage and it wouldn't restart; got the same dash light disco as before, hitting brake pedal kills dashboard, spoiler did the same party trick. Pushed the car back into the garage and thought I'd investigate later.

Stuck the battery on charge over the weekend - the Optimate showed it as in RED condition, ie flat, and did its anti-sulphate or whatever it is cycle before going into charge mode. Charge mode seemed to take forever, with the battery still heavy charging some 10 hours after going on which is pretty unusual for the Optimate; usually it'd have gone into trickle charge mode by then.

Anyway, eventually the Optimate showed battery as GREEN so I lean in and give the car a start. Fired up first time but with brake warning lights and ABS lights all illuminated and temperature gauge red warning light flashing away to itself - in other words, similar symptoms to low voltage as seen before.

More worryingly, after 15 seconds or so there was a very high pitched electrical squeal coming from engine compartment.

Not had a chance to get multimeter out and test down battery whilst engine off / on yet but my initial thoughts are pointing towards:
Alternator
Voltage Regulator
Earth Strap

Would this sound about right and is there anything else I should be considering?

Cheers

Arry
 
If you have a new battery, I would check to see if it was charging first.
Battery voltage should sit around 12v (+/- 0.5v) when not in use, and raise to 13-13.8 volts when engine running?
If voltage doesn't pick up then that would indicate a problem with alternator/regulator.
 
Panda996 said:
If you have a new battery, I would check to see if it was charging first.
Battery voltage should sit around 12v (+/- 0.5v) when not in use, and raise to 13-13.8 volts when engine running?
If voltage doesn't pick up then that would indicate a problem with alternator/regulator.

Yup, if I can get it to start again tonight then then I'l report back on the voltage whilst running.
 
Tested battery at the terminals engine off - 12.3v approx. Tested at the leads, exactly the same.

Started her up just now - started first turn of key and no weird electricals apart from ABS light showing.

Left her to idle for 30 seconds or so, then weird high pitch whine from alternators general direction started - lasted about 40 seconds or so then quietened down but think was still faint in background.

Checked voltmeter and just over 14v. Tested with meter on terminals and getting strong 14.4v at idle.

However. Then turned engine off and back on again, then again. Next time round voltage on dash dropped to 10v, lights went weird again and car started lethargically - tested now and still showing 14v but voltmeter showing 10v approx. Eventually car died, spoiler raised and failed to restart - not even a click.

Battery still showing 12.3v and Optimate says it's Amber for condition.

It seems unless battery is 100% at full charge I'm having issues despite the voltage when running appearing to suggest it is charging.

Convinced now at least it is a charging system issue rather than ignition switch, but unsure where to go from here.

Any advice appreciated.
 
I would agree with charging system issue. 14.4v seems a little high but not necessarily the problem.

I also have an Optimate connected to mine and would suggest you take no notice of the lights on the optimate...mine changes every time I look at it!
Weirdly enough it seems to do the job...but when its connected It can sometimes read 11.5v at the battery when its in fully charged mode....cant explain it but it starts ok, so I haven't worried about it!

might be an idea to go to a local auto-electrical shop and get them to confirm the lack of charging.... before investing in an expensive alternator replacement job?
 
Panda996 said:
might be an idea to go to a local auto-electrical shop and get them to confirm the lack of charging.... before investing in an expensive alternator replacement job?

Agreed. Also, there is a very good chance they can rebuild it, which would be MUCH cheaper than replacing it. Should you decide to replace, the guys over on this side of the pond have discovered that the one from a 997 have more output (150A vs 120A), will bolt straight in and is MUCH cheaper.
 
TBH on a 16 year old alternator and voltage regulator, and for the ~£250 ish they rock in at, albeit expensive I'm minded to replace as part of ongoing maintenance / peace of mind of going through old parts for reliability's sake.

However whilst I'm happy to shell out for the bits and fit them myself, I'm more intrigued as to what the problem actually is - mainly because I believed the original battery's failure to have been the problem but actually, in retrospect, it's more a symptom of the underlying cause of trouble.

What I can't get my head around is:
a) how intermittent / sensitive it is; and
b) why the multimeter can still show 14.4v with ignition on when the Voltmeter shows 10v, I've got disco lights and dancing spoiler and the Voltmeter was reading perfectly accurately just a couple of moments beforehand.

Confused of Essex :(
 
I suggest you take the drive belt off and try to turn the alternator , im guessing its pretty seized .

If not that try the other pullys as it sounds to me like something is dragging so much on the engine that its stalling it.

Possible its an earth fault but check as above and repost please.
 
Will give it a whirl at weekend. Ta
 
arry said:
TBH on a 16 year old alternator and voltage regulator, and for the ~£250 ish they rock in at, albeit expensive I'm minded to replace as part of ongoing maintenance / peace of mind of going through old parts for reliability's sake.

However whilst I'm happy to shell out for the bits and fit them myself, I'm more intrigued as to what the problem actually is - mainly because I believed the original battery's failure to have been the problem but actually, in retrospect, it's more a symptom of the underlying cause of trouble.

What I can't get my head around is:
a) how intermittent / sensitive it is; and
b) why the multimeter can still show 14.4v with ignition on when the Voltmeter shows 10v, I've got disco lights and dancing spoiler and the Voltmeter was reading perfectly accurately just a couple of moments beforehand.

Confused of Essex :(

I would have the same view if it were mine.. Swap it anyway for piece of mind, etc..
However, I would get the original unit repaired. The misbehaving component is probably an electronic part, which is easily identified and replaced. (The alternator windings are probably Ok as the unit wouldn't produce anything at all if they were blown) The VR unit usually houses the Diode pack (to convert the AC to DC) If a diode is blown it could cause the weird voltage fluctuations you are experiencing. (the negative cycle voltages are not being converted to positive to give an even DC voltage.)
A fully re-conditioned Alternator (in my opinion) is as good as new. But if you are happy spending the extra for a new unit then that's great also!

And as previously mentioned. I would also definitely clean up all the earth/ground points you can get at.
Let us know what you discover on the weekend.
Good luck.
 
Swapped the alternator out yesterday - wasn't too bad a job but the bruises on my arms tell a different story, oh well a little personal sacrifice to the car fixing gods.

Was about to nip round front and reconnect battery when I noticed some moisture on the deck is under the engine. Air box off again and it seems I must have just caught the little plastic hose joiner which bolts up just to the right of the alternator, as it was leaking a bit of coolant. A little tug on the hose and it was so brittle the nipple snapped off clean.

Oh well, least I spotted it in time, and it appears it needed changing anyway as both nipples were extremely brittle. Found the part today and it's less than a fiver so no harm done, apart from having to wait a week or so to find out whether I've fixed the issue.
 

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