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[Lazydocker]

Need some advise here...

Battery light glows very faintly when a load is on. It seems to get slightly brighter with increased RPM and gets dimmer the longer the car has been running. I have cleaned the body earth poins and currently have a good quality jump lead connected between the battery 0V and an engine bracket for earthing but not a massive improvement.

Is this likely to be a poor/corroded connection at the Alternator and how much of a PITA is it to get the alternator off?

[RobG]

Voltage regulator failing.
Multiram setup out.

Aux belt off.

Disconnect battery

Remove the two securing bolts (one end is torx, the other end hex)

swing the alternator out and disconnect the two rear electrical connections.

[Lazydocker]

Voltage regulator failing.
Multiram setup out.

Aux belt off.

Disconnect battery

Remove the two securing bolts (one end is torx, the other end hex)

swing the alternator out and disconnect the two rear electrical connections.

Thanks Rob... I reckon it may actually be the connection at the regulator as these do suffer with corrosion but need to get it out to check I suppose. TBH, it has been like it for over a year now, just starting to git a little worse now (probably because I want to use the heated seats/screen again!) so could well be the connection.

How long (roughly) do you reckon it takes?

[Andy B]

.....  the battery 0V and  .....

Which one is that? I only have a +ve & -ve on my battery. 
You've been taking too much notice of the electrickery sparks here 

[Andy H]

.....  the battery 0V and  .....

Which one is that? I only have a +ve & -ve on my battery. 
You've been taking too much notice of the electrickery sparks here 

That will be your earth connection 

[Lazydocker]

.....  the battery 0V and  .....

Which one is that? I only have a +ve & -ve on my battery. 
You've been taking too much notice of the electrickery sparks here 

That will be your earth connection 

I may have been absent for a couple of weeks but knew someone would bite if I worded it like that

[Kevin Wood]

Does it brighten with all loads or just some? Could also be some voltage drop on the supply to the instrument panel - but most likely an alternator that has a failed diode in the rectifier pack. If you can get to the terminals connect a voltmeter between the b+ and indicator light terminals on the alternator and see if you get a significant rising voltage here with increasing load.

Kevin

[Shallow Al]

Mine did this back in the summer and the + battery terminal was getting hot. Was the crimped joint between the main cable and the battery terminal itself going bad.
I got a new terminal and cut back the old cable and joined a new piece of cable between the two. Its been good as gold since. I think it was you Kevin who told me about it. Worth checking anyhow. I only noticed it at night and the more load I put on, the brighter the warning lamp got.

[Lazydocker]

hmm... I must admit I was convinced it was a connection issue and my terminals do seem to get quite hot!

Perhaps I should be looking at the terminals first?

Yes Kevin, it doesn't matter what load is applied, the light glows slightly brighter with anything. As a matter of note, the reading at the battery terminals never drops below about 12.4V and this problem did improve considerably when I replaced the battery earlier this year (which I may well have to do again  )

[Andy H]

Have you seen MarkDTM's guide Repairing the Alternator?

I found removing the alternator relatively easy (for an Omega.....).

If I were in your position I would check the connections first but be prepared to take the alternator and have a look under the plastic cover to see what state it is in.

[Kevin Wood]

hmm... I must admit I was convinced it was a connection issue and my terminals do seem to get quite hot!

Perhaps I should be looking at the terminals first?

Yes Kevin, it doesn't matter what load is applied, the light glows slightly brighter with anything. As a matter of note, the reading at the battery terminals never drops below about 12.4V and this problem did improve considerably when I replaced the battery earlier this year (which I may well have to do again  )

Forgot about the most likely cause! If it's dropping to 12.4 with the engine running and the terminal(s) are getting hot fix them first. Normally the positive battery terminal fails as the crimp becomes loose where the cable from the alternator connects.

Kevin

[Lazydocker]

hmm... I must admit I was convinced it was a connection issue and my terminals do seem to get quite hot!

Perhaps I should be looking at the terminals first?

Yes Kevin, it doesn't matter what load is applied, the light glows slightly brighter with anything. As a matter of note, the reading at the battery terminals never drops below about 12.4V and this problem did improve considerably when I replaced the battery earlier this year (which I may well have to do again  )

Forgot about the most likely cause! If it's dropping to 12.4 with the engine running and the terminal(s) are getting hot fix them first. Normally the positive battery terminal fails as the crimp becomes loose where the cable from the alternator connects.

Kevin

Like I said, was my gut feeling. Especially as it seems to have gotten very gradually worse for about a year

Can the +ve connection be crimped again or is a replacement needed?

[Shallow Al]

I think I gave mine a good tug, if you pardon the expression
and gave it a spray with WD40 to try and prove it, and it made the light go out. Lasted a week or two until I could make a proper repair.

[Shallow Al]

I didnt have any means of crimping the joint as it was very tough. I considered soldering it, but it would have been difficult to get the joint hot enough without melting the insulation of the cable.
In the end I cut back the cable a little and put a heavy duty connecter on and put about 6 inches of new cable in, to a new battery terminal.

[Andy B]

I've just started my Omega to move it, & it appears that my car has come out in sympathy, the charge light is glowing very dimly at idle.  I noticed that my battery cable was warm ages ago & chose to ignore it.
A job for Wednesday I think.