Electrics problem – indictors/wipers/brake FIXED

sbraud · Post by **sbraud** » 24 Jan 2005, 22:54

It never rains but pours… just working through my list of Xantia problems and then this today !!!
Indicators, wipers or brake pedal cause some sort of shorting/switch off of those circuits and the dash battery warning light comes one. I can also hear what sounds like a relay, from foot well relay area, sound once and then nothing.
If I switch off ignition and then switch back on again, then all is normal with dash start-up. All other circuits seem fine - lights dip, full and fog, horn, vent fan up to full, hazard lights, rear window heater, elec windows… all at the same time and no problem (which must draw some volts) but as soon as I use indicator/front wiper or press brake pedal (not at same time) then on comes battery warning light and off goes most internal electrics. (radio, vent fan, speedo, indicators, rear brake lights & elec windows, wing mirrors etc)
I changed the indicator relay because I had the ticktickticking from it for a while and was hoping that might be shorting something else… but of course was not the problem.
Has anyone see this or know what it may be?
Does it sound like a common earth problem and if so, any pointers as to it’s location?
Cheers
Steve

Panjandrum · Post by **Panjandrum** » 25 Jan 2005, 02:01

The ticking from the indicator relay is down to a known problem with the switch, nothing to do with the relay.

AndersDK · Post by **AndersDK** » 25 Jan 2005, 03:39

If you get the dash battery warning light on when you switch on a circuit - you may have a shortcircuit to earth in that circuit.
A way out :
1) identify which circuits causes problems.
2) remove each fuse in turn to the circuit(s) until the problem disappears
3) trace the cabling and units to the problem circuit(s)

sbraud · Post by **sbraud** » 25 Jan 2005, 12:24

Thanks Panjandrum and Anders, [;)]
Was hoping to get on with some other bits on my Xant-to-do-before-MOT list... but looks like I’ve got a new challenge. ``No more challenges, Please!!’’ [V]
Anyway thanks again.
Steve

PeterMann · Post by **PeterMann** » 25 Jan 2005, 20:02

There are 3 earth points concealed under the battery (the worst possible place in terms of corrosion), and removing the battery allows access to a further 7 earth points immediately behind the battery.
Loosen each of these, insert some gearbox oil onto the bolt thread and the electrical termination, and tighten up. Magically fixes all sorts of electrical weirdness.

sbraud · Post by **sbraud** » 26 Jan 2005, 00:58

Thanks PeterMann,
Spent this afternoon trying to find and checking earth points, but had no idea of these under and around battery. Thanks for the advice, I’ll have a look at these tomorrow.[xx(]
Cheers
Steve

sbraud · Post by **sbraud** » 26 Jan 2005, 23:39

OK.. taking it back a few months. (trying to work the problem, not other way round)
I noticed some many weeks ago that whilst driving to work in the dark my alternator dash light would slightly illuminated when I used brake light or indicators - even after 25mile constant M25/A2 driving . Sometimes instrument illumination would dim in sequence with indicators. I thought at the time `bl**dy H*lfords’ as I’d only put in a new battery in August - 5 yr guarantee at least, I thought.
Didn’t occur to me to think about the alternator until now.
I spend today checking & cleaning the 10 earth points under/around battery. Dismantling airbag/steering wheel/cover over stalk so I could undo all plugs to indicators, horn and wiper stalk switches. Lastly taking out fuses one-by-one to see if I could find an earth problem. None of the above made any difference.
Then I remembered some alternator problems mentions on here, lots of weirdness and some similar to my problem. Also saw a post from Anders regarding alternator warning light being just a balance between 12v in from alternator and 12v battery supply. So went to get multi-meter to check out out-put, and it’s not working. I’ll pick up a new one tomorrow to see what alternator is up to.

sbraud · Post by **sbraud** » 27 Jan 2005, 22:59

Not good news.
Tested battery 12.5v – ignition off & 14.2v ignition on
Alternator main supply is kicking out 14.3 and small green wire from alternator is kicking out 14.4v - so I’m <u>assuming</u> that shouldn’t be too much of a difference to cause ignition warning to come on. Well not only when indicator/break light and wipers are in use.
The only thing I can think of is these three use relays and there could be some short circuit here.
The other symptom is all electrics work fine, radio,electrics windows but use indicators/break and they too switch off. Is there some safety cut-off going on here or this that my desperation!
Anyone know of any other earth points to check – apart from the 10 under/around battery and does ECG have anything to do with circuits affected?[V]

sbraud · Post by **sbraud** » 29 Jan 2005, 00:16

So there I was last night thinking, three circuits, one problem. So I dusted off Haynes manual... where the wiring diagrams are ( I hate wiring diagrams) and eventually light dawned on Dunder Head… They all have the same ignition switch wires in & out. So not believing in coincidences I looked for some more. Map reading lights and rear wiper for starters, so went out at about 11.30pm in the rain to see if my theory was right, and yes these too had same symptoms.

This morning I checked out first feed to/from ignition switch with multi-meter and guess what... 3 volts. Gotcha…
Spent the afternoon cleaning out ignition module which had a big build-up of carbon deposits. Tried it out before it got dark and seems to be working fine.
Tomorrow I’ve got to put it back for real, along with all the other parts I took out to get to ignition… Just hope immobiliser is going to behave as there seems to be some set-up with ignition key and immobiliser sync…
Big Thanks to all who helped!
Cheers
Steve

PeterMann · Post by **PeterMann** » 29 Jan 2005, 07:03

Steve,
Ignition switch problem you describe is reminiscent of common failure in Heater Blower Fan, which is best fixed by retrofitting a relay so that the main switched load is no longer carried by the ignition switch. If I were in your situation, I'd do this before refitting the shroud around the steering wheel. I photographed the parts that I made, and can send a circuit diagram. my email address is nicolewis@optusnet.com.au

sbraud · Post by **sbraud** » 31 Jan 2005, 12:56

Cheers PeterMann,
I appreciate the offer... but for once the gods are smiling on me. Immobiliser is behaving for now, which, of course, means I’ll be emailing real soon, as the gods seem not to smile for long! [;)]
Thanks again.
Steve