Alternator Gearbox faults on start up only in the morning..

petie said:

Oh dear, not too sure what to say to that but I have to do something.. Having said that it started perfectly this morning again - on the third turn - but thats freaky.. It would appear that my voltages are low anyway and so I will have to get that sorted and see how I get on from there... They do sound very similar mind and a little worrying... Sure 'ever onward' as they say and see what happens..

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Fanny beat me to it. If your "O" rings have been leaking and the carpet is wet it won't help either.
There is a voltage drop/bad connection somewhere. Could still be fuse box.

On a phone, but a brass brush to clean contacts if you can't get contact cleaner then chemists sell isopropyl alcohol

Keep your eye on the prize. Replace or refurb the alternator and I am confident your problem will be resolved.

Got the dreaded "Alternator Fault" message today after hurridly running out to close an open sunroof in the middle of a downpour. Engine wasn't running, message appeared halfway thru closing.

Should I panic?

Unless the OP has a refurbed alternator with an up rated controller. You should never see 14.8 volts changing rate on a P38 diesel. 14.2 volts is the maximum you should ever get. You will get up to 14.5 on a post 2000 4.6 fitted with an 150 amp alt, but not on the diesel.

i had this problem on my 1998 DSE p38 a month or so back and i found that mine was voltage related i found if i had the radio on with out the engine running when i come to start it is would play up but if i dont leave anything electric on then it starts perfectly every time also i had the dreaded hotstart after cureing this it helped alot just saving top get a new alternator and the biggest battery i can possibly get so it will sort my problem all together

Turn on as many electrical gizmos as you can then check alternator output again, just after your first start if the morning... Alternators can sometimes give decent output but fail to ramp up sufficiently under load.

Failing that, have a THOROUGH check of the engine bay fuse box, as others have suggested... ie remove it and take it apart... So many electrical gremlins caused by corrosion and scorching in those things...

I just want to finish up this thread by saying that at long last I think I have this sorted.. At the moment its been perfect for about three weeks and I'm delighted. We removed the ECU from its housing, cleaned and re-crimped all the terminals and replaced it. Simple as that. Thanks everyone for the advice, really really appreciated it and fingers crossed that it stays healthy.