I was driving to the misses place the other night and after driving for less than 5 minutes the car dash lights went off, followed by all the external lights and then I chugged to a halt! I managed to get the car to a lay by which was opposite and called for help.


The symptoms suggested the battery had died, so called my daughter for a jump start (thank fewk I had mine with me) as I jump started the car and it ran OK. So as to not temp fate I drove back to my place but within a few hundred metres it chugged to a halt, again with the same symptoms. As I was only yards from my house I got a lift back and got the battery from my other car and fitted it.


BINGO, it works a treat and I go home. Chuffed with my work I take the car to work the following morning and after the short 2 mile drive it chugs to a halt just as I get to my parking space. I thought that as the newly fitted battery had lasted this long it must have been the alternator not charging and I was running on battery power, checking it with a multi-meter it was only indicating 12v with the engine running with main lights, fog lights, AC and accessories all on.


So, to eliminate the fact that both batteries are fewked I trickled charged the spare, fitted it then borrowed a working alternator. The alternator is now fitted but I left the car running for a few minutes and the fewking thing just stopped working AGAIN! I am still only getting 12v across the terminals with the engine running.


It's a JDM WRX Blobeye.


Any ideas? I think this is one for "alcazar".

 

Ian, years ago I had very similar issues on my classic WRX, and found that there was a break in the live to the alternator, how I came to find it was by snipping the live a few inches from the connector block and running a temporary wire to the live on the battery. It worked.
Just my experience and may be worth a try.

 

Smart charge issue on alternator

 

A few years back twigsters had a similar problem and found there was a break in the main relay fuse in fuse box under the bonnet, it's worth a check because these do blow and since then we've repaired a few, my type r si bs type r twigsters and I believe matts. It could have a break in the connector and they are very hard to see and what happens is it'll touch and work and as it gets warmer the join gets bigger and stops from working and cuts out all power. Not saying it's def the cause cap but worth a look it's a 2 min job. If your stuck give me a call I'll run you through it.

 

Dan, not that smart obviously.

 

I've had issues with battery going flat,not when driving but when left for a few days.
I was told as I don't use the car often to drive with sidelights on as this makes the smart charge kick in on alternator and keep battery topped up.
Surprisingly it solved the problem.

 

my recent electrical gremlins were a result of water ingress

 

While you've got your head under the bonnet, also check the earth straps from the block to chassis.

 

Could be the alternator, but my thoughts lean towards a poor earth somewhere.

I'd be inclined to a) clean up all earthing paths, b) fit some new heavy duty earths between engine and battery and c)get the alternator checked out.

Other things to check: the fuel pump and especially it's electrical connection which gets moisture in it and becomes unreliable.
Coil pack(s), look for moisture and cracks......as the engine heats up, the crack widens.

It MIGHT also be a missing/split etc vacuum pipe: when the car is cold it runs OK dues to having a lot of fuel. Once the fuelling is brought down, it might be too lean to run.

HTH

 

Had a similar problem in my transit. Think it was a fault with the alternator.

 

Alcazar,

The alternator was changed and the problem is still there. BUT I have found a potential cause. Pictures in a bit.

 

Oooooh, excitement....

 

I ran a spare battery cable from the alternator to the terminal as mentioned above. I was still getting the 12v's with a mult-imeter across the terminals. So after the symptoms occurring again with the new alternator it was time to check the main relays and fuses.


Starting at the front and as if by magic! The blade is still inside the fuse and corroded.





And inside the fuse box the corroded receiver.



I hope this is the fault but I will check all the other fuses and relays tomorrow. But I think a new fuse box is needed unless I anyone knows a fix?

 

Yes mate I know of the prevention, I always drive with the sidelights and/or headlights on.

 

A bit of an update.

I sourced a new fuse box but then stumbled upon something I could have checked.

The actual relay plug is not part of the fuse box and detaches.

And is detachable but is at the front end of the fuse box. I managed to remove the cable end from the plug. As I did it bits of copper and dirt fell from the plug and this is what I found.


The corroded spade end had detached from the cable, had rotted in the block fuse and the receptor was full of corrosion and dirt.

 

Copper is quite reactive in the presence of air and water, heat helps the reaction and any salt does so too, adding electrolytic reaction.

On my Xantia, the main cable from the battery to starter burned out...simply because it had oxidised along it's entire length, making it have too high a resistance for the current, and producing unacceptable amounts of heat.

Cost me £40 to get it diagnosed and replaced, after it melted the solder in the connector at the battery end, some of which melted the battery top, fell inside and destroyed a perfectly good battery!

 

Bloody hell captain good job you found that and didn't get cought out in the middle of no where

 

So today I fitted a 50 amp fused link to the cable ends and the car started up, hurrah!

After a few minutes it cut out as it as done since the fault appeared, boo hoo!

As it stands I have fitted a new alternator, battery, fuse box and relay but it is still fubar'd. The car will start and cut out after a few minutes, it dies, the dash lights are dim, the fuel pump is still priming and will restart if I leave it a 1/2 hour or so.

Any ideas?

 

Find another similar?

Battery not holding enough charge?

 

Find another similar car perhaps, LOL!


Initially all the dash lights etc are fine and they randomly extinguish as the car starts to dies, the front right HID goes first (JDM Blob's are standard fits, not after market). There is 11.89 volts in the battery when the engine dies or with the engine off.


After a while the dash lights, interior light etc. are fine, I start the car it runs, drives, lights etc all work but it dies again after about 5 - 10 mins!


Grrrrrrrrrrrrrrrr!

 

It does sound a bit like a smart charging issue as mentioned before. Is the replacement alternator a known working one? What voltage do you get at the battery immediately after the car is started? Static battery voltage should be about 13V or so and running engine around 14V.

 

Yes , the alternator was from a working Spec C, JDM for JDM just in case. The battery is always registering 12v or near as damn it no matter if the engine is running or not.

 

What about the voltage when the engine is just started?

 

Ignore me just seen the last post. That alternator is not charging at all, looks like you need another one or else try switching on the rear window de-mister when the engine is going.

 

Errr, explain?

 

First the voltage reading at the battery posts with the engine running should be around 14/14.5V if the alternator is doing its job properly. You need to be 100% sure that all the connections are clean and secure if you think your replacement alternator is working. This includes the large earth cables around the engine/engine bay and at the battery itself. If I remember there's a large cable bolted to the alternator as well as a smaller push on plug. Check all.

If all is well with the wiring etc then you need to introduce some kind of load to the electrical system for the smart charging bit to produce some power. So switching on the de-mister, headlights or something like that should be enough. If you still haven't got 14V at the battery posts after all of this then I'd be inclined to think the alternator is dead.

 

Thanks for the help mate, I really appreciate the advice.


I have started the car then turned on every single available accessory, in order to induce a load including the AC, Radio, lights etc. The alternator is good as it was removed from a working Spec C Blobeye, but I will check the voltage on initial turn of the key.


I'll pull all the fuses, SBF's and relays again tomorrow but I also have a top Subaru mechanic coming up to check on Wednesday for a mooch about.


Cheers butty.

 

It'll be something daft I bet. Let us know how you get on.

 

Ian what size cable have you used and what connections have you used for the new inline fuse? Have you tried just connecting the wires without fuse or relay just to see if this is the problem or not. Also check the other fuses relays chances are another relay has gone? It sounds like when the car gets hot that's when the problem starts now that would say to me that there is a gap in the wire connection and seperates when hot shutting down the engine. Are you going to the meet on wed and will you have the car? If you are I'll have a looksy

 

Yes Daz.


The broken blade turned out to be the ABS unit slow blow fuse, but the issue does seem to be thermal related.


Unless I can get the car running for longer than ten minutes then I will not be at the meet.


Dean from Three Arches is coming up Wednesday after normal hours to the Man Cave.