Helps to know a few more details....year, engine, what is doing, what it isn't doing, whats strange, any troubleshooting you have already done....Anyone in cornwall who's a whizz at p38 central locking problems or if not is there anyone who wants to watch me burn the annoying thing
Without you telling us what the symptoms are we would be here till kingdom come postulating ideas...!!
p reg 96 4.6 V8 - alarm stopped working, central locking did work apart from passenger door. It then stopped working with the fob but would work with the key for awhile then that stopped !!!!! Boot wont open either. Havent tried much yet coz don't no where to start really.
Datatek
Well-Known Member
Assuming the battery is good (12.5 volts or more) look at the drivers door lock assembly micro switches.
Datatek
Well-Known Member
Brand new battery means absolutely nothing, check the voltage when it's been stood for a bit.
Datatek
Well-Known Member
What do you think is a good voltage?
Should be around 12.5-6 when been stood a while and at least 13.8 when running at 2000 rpm with everything switched on. Any less than that and your alternator is tired.
Addendum to my post above.....or 13.8V with load as per the Wammers comment!
That is the max Ant for other than the 4.6 with the 150 amp alternator which is around 14.5 or 7 can't remember. But alternators tire, so anything around 13.8 with everything switched on at 2000 rpm i would be happy with.
If its low it will cause allsorts of problems...P38's hate low volts and duff batteries.
Datatek
Well-Known Member
We have been round this loop umpteen times, lead calcium low maintenance batteries need higher charge voltages, all the P38's I have tried have 14.2volts at 2K rpm, any less will not fully charge a modern battery. Up to 14.6 is safe, 13.8 is marginal and will not keep the battery fully charged unless long runs are the norm.
If the alternator is set for 14.2 volts and is actually producing 13.8 volts it could well be a diode failure.
If the alternator is set for 14.2 volts and is actually producing 13.8 volts it could well be a diode failure.
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Datatek
Well-Known Member
12 volts = battery almost flat, 13.5 volts = alternator fecked or the battery is so bad that it's holding the charge voltage down, or the connections are bad.
Datatek
Well-Known Member
Alternators do not "tire". The regulator is solid state, it either works or it does not, the diode pack is solid state, diodes fail but do not get tired, brushes wear but generally also either work or stop working, sometimes intermittantly.
