What would cause this?

[amazon69]

Evening...all ideas welcome here from those more in tune with electrics than I
(which is probably most of you)...My amazon died today, very unusually, whilst sat in traffic in rush hour..just sat there, all good, ticking over sweetly, then silence. Turned key, no dash lights, nothing, no response at all. Arse. Popped bonnet, fiddled, all seemed fine. My first thought was dead battery due to bad alternator. Tried again, nothing. Fiddled a bit again, although all seemed well, nothing even remotely loose etc.
Got back in, turned key, dash lights on, off she goes. Now what would cause that? All earths are good, all connections seem good everywhere, all fuses good. Ignition switch? wires and connections there seem tip top too...
I am a little confused, and I don't want it to happen again, can't have the confidence in the beast going.
Any ideas? Thanks.
Dave

[austingipsy]

When you fiddled what did you fiddle with? My amazon's done this a couple of times and all that was required was the slightest tightening of the positive battery terminal. Appeared tight enough but one flat turn on the nut made the difference between a good connection and nowt. Hope it's as simple for you !

[asneddon]

Lucas fuse box? Replace it with a rebuilt one as a mater or course.
Also, make sure you have electrical contact grease between your battery terminals and clamps. Things can look good there, but it's often the culprit.

[Steve121]

yep, could well be a dodgy fusebox... had strange things happen to my amazon with the old one.. no horn, indicators, wipers, lights etc etc
cheap to replace!

[amazon69]

hmmm...cheers all...I suppose it could be the fuse box, although I didn't touch that when I fiddled...I just checked coil connections and battery terminals, and alternator connections, all of which were fine. I have since checked and redone all the earths, but they were super clean and tight...it is very odd..as a small test I took out the top fuse, and had no dash lights, but the car still started...so possibly not that. Am confused.

[amazon69]

Can you get new fuse boxes? I seem to remember that you can't for some reason, and I suppose it would make sense to put a modern one on anyway so I can use 'normal' fuses...what have people used? Thanks.

[AidanC]

The earth strap can run very close to the exhaust - its unlikely to cause complete electrical failure - usually just starting problems due to the amount of current required but its condition and connection to the chassis might be worth a quick look. Seeing as you were sitting in rush hour traffic, heat soak may be an issue so I'd be inclined to look at anything electrical that passes near anything hot - the route of the positive lead from the battery to the starter might also be worth a look - its supposed to be attached to the fan housing in the bulkhead on its way to the starter but may have become unattached.

[hairyapple]

Things don't just go bad while sitting at a light in a car like this. The fuses are the first thing I'd check but a bad battery connection could very likely be the cause as well, especially since absolutely nothing was working , that's where I'd go first no matter how good they all look.

[amazon69]

Cheers guys...it was the sudden going bad from nowhere that confused me too..like a light going off...I will put a new fusebox on come Tuesday or so, but it does -seem- ok the one I have....all other cables are routed correctly..tis odd, but it will be something simple, always is...

[Andrew (UK)]

The circuit for the ignition switch and starter motor is not fused so if the starter did not turn then the problem is somewhere from the charging circuit, battery etc, starter motor to the ignition switch. I have heard of cases where having a heavy bunch of keys hanging off the ignition key can cause the ignition switch to fail over time. You should also check the main grounding points for the charging circuit, battery and engine block.

[Ron Kwas]

Forum;

This thread is all over the map!...I realize everybody is trying to help here, and I don't wish to jump all over anyone's post, but presenting irrelevent or justplain incorrect info doesn't...going back to the initial post and stated symptoms:

1. IGN failing, accompanied by no dashboard lights like OIL and AMP Indicators, and inability to energize Starter suggests a complete collapse of the electrical system which is consistent with symptoms: "Turned key, no dash lights, nothing, no response at all"...I have had this occur due to a high-current short on system (within solenoid, and it was accompanied by temp-gauge heading for the sky instantly, and smoke from the groundstrap at engine as oil burned off due to the high temps with the resulting megacurrent), but I can't think of any single connections opening, then miraculously fixing itself to allow starting and normal running (without further symptoms) which would cause that! Vehicles have two power sources...the battery, and the generator/alternator...both would have to be off-line...for IGN to stop functioning...unlikely, and the battery was certainly not, especially when motor was able to be restarted...so that suggests an intermittent collapse of the electrical system...most unusuall! None the less, it is important to assure all high-current connections (battery, starter, chassis strap) and charging system (Gen, Reg, Fusebox),and finally IGNition (Switch, Coil, Dist) are clean and tight... Some pretty whacky symptoms can occur with poor or intermittent connections!

2. Amazons did not have Lucas fuseboxes, nor ANY electrical equipment (thank God...a hundred times!)...and removing every single fuse, normal or abby-normal, would still not disable IGN and prevent the motor from running...IGN being a "mission critical function" is not fused. Fuse 1 blowing would result in AMP Indicator coming ON full...and this was not stated as a symptom.

I've given a lot of info here myself and none conclusive because the information on symptoms is just not sufficient to point to a specific problem...so I suggest you clean and tighten all connections in sight under the bonnet as a preventative (and ACZP: http://sw-em.com/anti_corrosive_paste.htm couldn't hurt). If a cut-out ever occurs again (yes, it's a serious pain, a safety hazard even, but they are thankfully rare), get as much information as possible on symptoms of electrical system and IGN to allow for logical troubleshooting.

Cheers, and Good Hunting from Connecticut!

[amazon69]

Cheers Ron, and everyone else...Unfortunately due to the hairy moment of the failure I was more concerned with getting the car started again than with data logging all the specifics about what was on and what was off etc, but I am aware that it was an unusual failure, and it is one that confuses me. Why the whole car should die to the degree it did, as though there was no battery in there, really confuses me..and for it then to work again 5 minutes later, and be fine up till now, is odd. If there is a next time, and I suppose there may well be, as I haven't found any causes, I shall endeavour to carefully log symptoms etc. I will also look out some of that paste, it looks like good stuff.
Thanks for all your ideas..this forum is great for that, even if it seems like everyone has an opinion...I am grateful for them all.

[Derek UK]

As Ron says, it's all a bit vague. If it was at night and your lights had gone out as well it would be a little easier maybe. I doubt if you checked them this time. I would check the tightness of the connections on the back of the ignition switch though. Luckily you were just sitting ticking over. Better that than zinging down the outside lane of the motorway..................

[SWAmazon]

Exactly the same thing happened to me last night, first in the queue at the traffic lights so a little embarrassing!
I went it the fuse box and the battery terminals and everything came back on. Like you the pressure was on and I'm not sure which was the problem.
Thanks for the battery terminal tip, I'll check that.

[Tail]

Can you get new fuse boxes? I seem to remember that you can't for some reason, and I suppose it would make sense to put a modern one on anyway so I can use 'normal' fuses...what have people used? Thanks.

In answer to that question, yes you can, i got one a little while ago, around £23 if i remember rightly from Simon at Brookhouse. just get the base though and use your old top as a new top was more than the fusebox if i remember rightly. It took all of twenty minutes to swap over.

Bugger must be tired i didn't see it was a 2009 thread resurrected. oops

[woodman]

Just a thought: unless you've made Ron Kwas's diode mod for electronic ignition then there is an electro-mechanical gap between 'normally on' and 'start' positions on the ignition key. At this point, small though it is, the system is totally off. If the switching mechanism within the key barrel is breaking down then maybe it could dither around that gap and cause intermittent shutdown?

[Bigbunt]

So I need to resurrect this thread... Just started my car up for a spin around the block (bad day therapy). It started right up, first try, no problem as usual. Got to the stop sign about 200 feet from my house and she stalled (no big deal, hasn't run in a few days), turned the key and absolutely nothing! Amp light goes bright red when the starter button is pushed (yes, it has the starter button conversion, for a long time), headlights work nice and bright. twisted the key all the way to the right (yes, it still works...)and still nothing. battery has 12.6 volts. haven't tested power at solenoid with meter yet, but totally confused. tapped on solenoid a little to no avail.
Ive got it off the road and will get it home tonight. I tried cycling the key energetically a few times in case the switch is dodgy but I just don't know what to try next? Doesn't seem to make sense!

[Derek UK]

You might have a failed battery. It can measure fine for volts but have virtually no amps. Car will jump start without any problems and will run bit the battery won't take a charge. Had this happen on my daily (Nissan) and the AA gave me a start. Volts fine but only 8 amps instead of 480!! On a modern, battery failure can show as all of the dash lights going crazy and flashing out of sequence. AA sold me a new battery which is currently on my Amazon. Same type and number.

[Bigbunt]

Headlights are nice and bright though so can't be the battery...otherwise I would suspect it. Will check ground at battery. How do I check ignition switch? Meter to starter at what terminals with switch hot? Kind of new at this and electrical not my strong point hence my dumb questions!

[Bigbunt]

Ron, I saw that you were on here; no thoughts? I was kinda hoping you'd weigh in...
I'm guessing though, that you would say the same as the previous response and check all connections. Sorry to call out in desperation but the only time I really feel lost is when there are electrical issues. The frustrating part is that its such a straightforward machine and it has never left me stranded before. Guess thats part of the fun!
The confounding part to my amateur mind is that the headlights are full on bright along with dash and everything but the starter. about to bring it back home for a closer look...

[Ron Kwas]

Bb;

Being stranded is no fun in any sense...get this sorted and make this machine reliable!

If Headlights are at full brightness, they are getting full power, which means Battery and all connections along the way as well as components/connectors/switches are not suspect.

Startswitch supplies power to activate solenoid, which in-turn activates Starter. If Starter is not working, Startswitch and associated wiring needs to be sorted out.

Good Hunting!

[Bigbunt]

Well Ron, as you said, check your connections! It bump started so Iknew the ignition was intact. Found a dangling wire (there are several under my hood as this is a conversion from automatic) and lo and behold, reconnected to the solenoid and all is right as rain!
Must learn to not lose my head over these things but it had never let me down in the past year and i got used to that!! Thanks for your input, all!!

[Ron Kwas]

Bb;

GOTCHA! "...this is a conversion from automatic" is the clue!

Reference 122 Wiring Diagram: http://www.sw-em.com/122S%20Wiring%20Diagram.jpg

Factory BW35 equipped vehicles had a Starter Relay (Item 10) ...more like a Starter Enabling Relay really, which got a ground from Gearbox ONLY in Neutral to allow applying power to Solenoid...unlike a manual Geabox, there's no Clutch to depress to disconnect engine from Drivetrain, so Starter Relay assured Starting could only take place in Neutral...otherwise it could get exiting!

Since you now do have a Clutch and therefore manner in which to disconnect engine from drivetrain while Starting, you can loose this relay, and simply connect wires which formerly went to terminals 30/51 and 87. Done!

You might want to investigate all "...dangling wire[s] (there are several under my hood... " to prevent future issues...just saying...

Cheers