Alternator fault?

[Blackie]

Ok, I think I know the answer already, but just looking for confirmation before I rip it out again.

Car is a Vectra C CDTi 150bhp

Today the battery light came on whilst driving, the little usb charger/volt meter showed the voltage dropped down to around 11.3v. When I got the car home I did the old fashioned trick of turning the car off and back on and the battery light went out and the voltage meter is reading around 12.4v.

Prior to today the voltage typically would have been around 13.6v to 14v.

The alternator was changed on 13th June this year, not because it was faulty, but because at the time I believed it to be the cause of a squealing noise whilst the engine was running, which was the wrong diagnosis it later turned out.

I just went out and did a fairly unrealistic test of switching everything on and turning the steering wheel (the car has electronic hydraulic power steering) and the voltage dropped to around 11.3v again but it didn’t put the battery light on.

The battery was replaced in February of this year as well.

I suspect the alternator to be at fault, it thankfully has a years warranty.

What are your thoughts kind RMS folk?

 

[Mark_C]

Bad connection or faulty voltage regulator on the alternator.

 

[Blackie]

Yea gonna check connections tomorrow when the light returns lol. Shouldn’t be lose as I’m a tad anal when it comes to checking and tightening nuts and bolts, not saying its not possible though lol.

Truth be told I’m hoping it’s something simple like that! Will be easier for me time wise.

 

[stevieturbo]

More than likely it is the alternator.

 

[Blackie]

Just took it a quick run in it there and dare I scud myself, it seemed to be back to normal again, putting out around 13.7v again.

 

[dervsport]

What brand was the replacement Altenator?

 

[Blackie]

What brand was the replacement Altenator?

I can’t remember and I can’t place my hands on the receipt. Hopefully when I get a look at it tomorrow I’ll see. Failing that I’ll contact the motor Factors who sold it to me.

 

[colin84]

When I changed my alternator to a recon from Euro crap parts, soon after I had a permanent battery light on. A replacement regulator solved the problem.

 

[Blackie]

Seems to be an intermittent fault as the battery light came on today again, switched the engine off and back on again and it was gone. Gonna have to wait until this storm has passed as I don’t have a garage or a shed to work in.

 

[eamon343]

You didnt keep the old alternator?

 

[Blackie]

You didnt keep the old alternator?

No it was on an exchange basis. I wasn’t and still not able to write off the £50 surcharge that the motor factors were charging at the time, however in hindsight I really wish I had have just bitten the bullet as it were.