Corolla problem, long shot.

[Chris]

Guys, the current Mrs Chris came home today in her 55 plate Corolla saying that the water trap light came on followed a little while later by the battery light.

OK. Took alternator off, pulled brushes (very neat little unit) cleaned put back. Fuel filter off, drained put back primed engine running fine. Volts across battery 12.22v Water light still on, pulled the sensor connection light STILL on. Tried googling various combinations but no hits for those lights being on together.

She can take mine tomorrow, but any ideas at all - anything in the backs of your minds? I don't want to have to buy regulator unit if I don't need one. Probably stupid money

Any simple tests that I can do? I have pulled every fuse out and inspected it with a torch. Can't find any duff ones and everything else seems to be working. Battery indicator is still showing green in the sight glass. Belt is fine. Connections fine (cleaned) I can't find the engine earth strap though. So tomorrow I might run a quick bypass on that to the battery. It's in generally all round very good condition, clean, no rust, corrosion and no history of any kind of electrical problems.

Chris and Mrs Chris

 

[Crispin]

was the battery voltage 12.22 while the engine was running? if so, then it's a bit low and probably not charging?

edit:

I would have thought the water switch was a normally closed (opens when there is water) and by disconnecting it the car thinks there is still water. A red herring though maybe?

 

[Chris]

12.22 stopped, running dropped very slightly as there are dash lights etc but not much, then back to 12.22 when switched off again, so the battery is holding up well. That's after starting the engine a dozen times.

Not sure about the water trap. Normally the light on the dash is off. So if you cut the wire it should still be off, no? But it's on. I think that something is using that light in the dash as a combination warning light. Possibly.

Chris

 

[Jon Wildsmith]

13.7v should be the minimum you see with the engine running, less than that suggests the alternator isn't working / connected?

 

[Chris]

Indeed Jon, it points that I know, but in terms of the warning lights, why those two? If it were just the alternator surely just the battery light would come on.. Got a Google hit with exactly the same problem - no flaming replies! The only bit available on the alternator is the brushes pack. The rest of the electronics is all incorporated into the main winding it seems. Price? nearly 500 euros on Toyo, or something daft. I shall try some more tests when it's light tomorrow. Brushes were certainly making contact with shaft.

Chris

 

[Crispin]

Toyota recon jobbie...cheaper

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[Chris]

Crispin, there was never any question of me walking into the main dealer, presenting my arse, and saying "here, take what you need, I'd like a new alternator for my Corolla please"

You know me better than that. Bit frustrating that it doesn't seem to come apart more than that. I put new bearings in it last year and it's running sweet. Just not producing electricity.

C

 

[Crispin]

Looking back at my old thread, I paid 270 for toyo recon one instead of 515 new.
If you know a good rebuilder then rather them. I have an inherent distrust of them though.


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[Chris]

Local motor factor. It's Corolla! And, not mine.

C

 

[Graham]

Crispin, there was never any question of me walking into the main dealer, presenting my arse, and saying "here, take what you need, I'd like a new alternator for my Corolla please"

You know me better than that. Bit frustrating that it doesn't seem to come apart more than that. I put new bearings in it last year and it's running sweet. Just not producing electricity.

C

.
Hi Chris, now I totally dissagree with you,
With all your tools, and gas axe,
I am sure this little alternator WILL come apart more than that.
It might not go back together, but coming apart, I have no doubt.

Graham

 

[Chris]

Thanks Graham. Oh that's a real help!

Actually I may use my new angle grinder. Can't believe it doesn't have serviceable parts in it.

C

 

[adrianr]

Long shot. Have u disconnected battery for a wee while and reconnected to see if that works to reset an ecu somewhere?

 

[Chris]

Going to try that this morning. It does work sometimes, but still doesn't cover the lack of charge voltage. Must be the alt, but trying to be really sure before shelling out! Not given any indications - just failed. I will strip the fuel filter sender too and clean any contacts just to confirm that this is functioning correctly.

After a coffee that is.

Chris

 

[adrianr]

Good luck. getting rid of one problem at a time.....

in case alternator / parts needed i wonder if alternator for corolla is common to other models in range...

 

[Paul]

Sometimes an ECU can have weird issues if the supply voltage is low and it can switch off.
I wonder if the warning lights do a cycle on start up and show before engine is started as a test, but then the power is robbed during the start up by the engine because of charging/battery voltage problems and they stay on.

 

[Andrew Prince]

Chris, can't help with the alternator woes but perhaps you need to think outside the box...

Halfords have a special on ladies bikes here About a third of the price of a new alternator

PS: Make sure you have warm bedding in your RTT if you go this route...

 

[Chris]

Battery still holding good but deff not getting any charge that I can see. Was a good 12.5 volts this morning, dropped to around 11v when I cranked it but slowly recovered over a few mins. Not through charge, I don't believe. I have been applying the voltmeter to the alternator stud and that's making no difference. I presume that If I start it, then disconnect the battery and test alternator output, a big fat zero is pretty conclusive? Checked every fuse including the big ones this morning. All fine. We'll see if an ECU reset does make a change. Just a bit surprising that the alternator would die with no warning. It's clearly not draining the battery through a failed diode like many do. Looking like thick end of £225 for a new one. It is shared on other vehicles but this doesn't help with the price. If the internal gubbins were removable, I might be tempted to get a pattern part, take it out and put it in the genuine Denso one. But seems it's all solid state in there.

Chris

 

[Paul]

My local guy rebuilt mine for £45. Might be worth a try.

Direct Power 01730 710210 Petersfield.

 

[Chris]

I shall seek advice on that. Petersfield obviously not very local to me, but there might be somewhere.

Chris

 

[Ian Rubie]

Not much to add except the water trap light might be a false alarm, much the same way as an 80 dash lights up like a Chrismas tree when the alt stops charging.

Ian