Yaris '09 1NR-FE battery light on, alternator problem?

[Seb_90]

Hi all,

my gf's Yaris '09 1.33L 100bhp 1NR-FE stopped charging the Battery - the Battery warning light appeared on the dashboard. It was flickering on and off when we were driving back home and now it's on permament (we don't use this car for now).

I've checked the voltage with a multimiter on the Battery and on the alternator and both are just below 12V when the engine is running.

Is this defintelety the faulty alternator or can it be something else I could check?

It doesn't help, that the valve cover gasket leaked at some point and the alternator is completely covered in oil and grease. But electrical connections are clean.

 

Many Thanks,

Seb.

[Derek.w]

Its a alternator fault but it depends on car milage go for new altinator or strip it down replace carbon brushes and if milage ie bearings are on the way out replace those.

Try just cleaning brushes first but if spring pressure is weak replace all 4.

Tip if you stripping it down center punch maiting parts so you can line it back up on assembling.

 

[Cyker]

If you checked it at the alternator terminals while the engine was running it seems pretty conclusive that's the problem. Otherwise could also be cables, but if it's covered in oil and grease I'd be more inclined to share your conclusion that it's the alternator.

It should be fairly easy to get hold of a replacement from a breakers yard or pattern part.

Not a common fault tho', I think it's the first time I've heard of one going on that engine in this forum!

[flash22]

the alternator is dead, time for a new one

[Seb_90]

Thank you for the replies!

I am surprised it has died so early, my gf hasn's really used the car that much since covid. She did around 5000 miles in last 3 years. I should have paid more attention to the oil leak though 😞

It is a good idea to have a look at the brushes first, looks like I can access it without taking the alternator out completely:

I will try to take off the INSULATOR, EXHAUST MANIFOLD HEAT shield to gain access to the COVER, ALTERNATOR REAR END. Looks like there are only 3 nuts and 2 screws holding it in place.

Wish me luck 😄

[Derek.w]

Lots of video on the internet covering brush replacment but take out your brushes to measure cross section area if no mfg details on alternator.

[Derek.w]

The part in red that you have marked up will have a dust cover over the rings picking up the power.

It just slides off away from shaft end just clean slip rings with a dry cloth to remove carbon dust from the area before refitting brush holder.

If brushes come out over 15mm then press them in with a screwdriver to see if brushes are sticking.

You may have to wrap tape around brushes to aid reassembley then remove tape.

You may find brushes are soldered into holder at opposite end on a wire if no desoldering tool just grind or file it down but you need a soldering iron and solder to fit in new ones.

[bathtub tom]

6 hours ago, Seb_90 said:

It doesn't help, that the valve cover gasket leaked at some point and the alternator is completely covered in oil and grease. But electrical connections are clean.

I'd suggest it may be belt slip due to the oil contamination.

First of all, does the ignition light flicker when there's no electrical load?

Turn on the headlights and HRW, put your foot on the brake pedal. Does it flicker brighter? If so, you need to cure the oil leak, clean the pulleys and fit a new belt.

Perhaps not cheaper than going down the alternator path, but a permanent cure.

[Derek.w]

If you have belt slipping then it would also squeak with burn marks on the rubber belt.

[Seb_90]

An update:

Yesterday I went to change the Battery to the fully charged spare one but the car wouldn't start at all, just the starter was spinning. I've tried both batteries but no luck. I thought maybe it was dogy fuel left in the tank (I had two bars) so went and got some premium in a canister and filled it up and the car started fine. No warning lights on, running nicely, multimeter was showing 14.2V. I went for a little drive around and the warning light came back on just good 30 min later. 

Today I went to remove the brush holder to inspect it but couldn't get to it with the exhaust manifold being in the way. 

Unfortunately it looks like the whole alternator has to come out but that's where my DIY skills end and will be a trip to the garage 😞

Just to add, the alternator and everything below is covered in oil...