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Old 14th September 2019, 09:47   #1
pletevl
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Default Alternator output

Hi all.
My alternator is putting out 14.5 volts. Is this too much?

Pete.
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Old 14th September 2019, 09:54   #2
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14.5 volts is ok mate
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Old 14th September 2019, 19:40   #3
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Perfect.-----
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Old 15th September 2019, 09:24   #4
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Quote:
Originally Posted by pletevl View Post
My alternator is putting out 14.5 volts. Is this too much?
I would keep a very close eye on that Pete. 14.5 volts is regarded as the absolute maximum charging voltage. To put that in perspective, my C-tek smart charger is currently applying 13.71 volts when connected to my SD1's battery.

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Old 15th September 2019, 09:58   #5
pletevl
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OK. So different opinions.
My other cars are around the 13.5 mark too.
Would this voltage kill my battery?
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Old 15th September 2019, 10:05   #6
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It's normal for an alternator to put out 14.5 volts, if the battery is short of juice and demanding a high level of charge, however, if it is doing it constantly I would get the battery load tested to see if its holding its charge ok.

It may simply be that the air con is working hard and drawing a lot of juice from the alternator, but it's worth checking the battery, just in case.

Good quality chargers like Ctek will always do a better job at caring for the battery than the alternator will.
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Old 15th September 2019, 10:44   #7
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Quote:
Originally Posted by chillyphil View Post
It's normal for an alternator to put out 14.5 volts, if the battery is short of juice and demanding a high level of charge ...
It may simply be that the air con is working hard .
I think you're confusing voltage with current Phil. The charging voltage should be relatively constant, it's the alternator's current delivery which changes depending upon the vehicle's demands.
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Originally Posted by pletevl View Post
Would this voltage kill my battery?
As I said Pete, 14.5 volts is acceptable but it's not normal. I'd suggest that you activate the IPK diagnostics before a journey and monitor the charging voltage. Does it vary depending upon engine speed and/or heavy current demand?

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Old 15th September 2019, 11:23   #8
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Unhappy Alternator charging voltage

I just checked my 2004 ZT 260. My charging voltage is also exactly 14.5 volts on tickover. At 2500 revs, still 14.5 volts. I never thought about this, but I have had minor battery acid leakage which caused me to remove the slightly corroded battery plate and refurbish it. I also found that someone hadn't put back in the battery drain tube properly. Since the drain was installed correctly, the corrosion has stopped. Anyone know where the voltage regulator is and should it or can it be altered to a lower voltage? My ctek charger also seems to be at 13.7. I'm taking a keen interest in my electrics just now as I have a 1.4 amp current draw from the battery with ignition off. If I remove the 50amp fuse from the fuse box, the current drain stops completely. Anyone got a circuit diagram for tracing what comes off FL3
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Old 15th September 2019, 12:28   #9
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Quote:
Originally Posted by edwardmk View Post
... I have a 1.4 amp current draw from the battery with ignition off.
Are you waiting longer than 18 minutes after turning off the ignition Edward?
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Originally Posted by edwardmk View Post
Anyone got a circuit diagram for tracing what comes off FL3
If your 2004 car has the later type of passenger compartment fusebox, the answer is as follows:

Power wash relay and fuses 28 to 36, 38, 40, 42, 44, 47, 49, 51 and 53 of the passenger compartment fusebox.

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Last edited by SD1too; 15th September 2019 at 12:45..
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Old 15th September 2019, 12:34   #10
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My voltage changes depending on the demand from the vehicle, ranges from 13.7 to 14.5.

I thought this variation was normal?
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