2005 RRS TDV6 HSE

Took the car for a short drive today and it was reading 15.2 volts (through cigarette lighter socket). Battery is new. Do I need to replace the alternator?

Rev the car to 1000rpm. Note voltage.

Rev car to 2500rpm+. If the voltage has increased significantly, then yes, regulator in alternator probably fault.

When using the car, keep the revs down.
Don't use sport mode.


Could also be a cheap voltage read out.
Use something else to check it

Thanks for that, will try in the morning and report back.

The reader records 13.8 volts in my other car so I am satisfied it is fairly accurate.

15.2v is perfectly normal

Every morning my radio and satnav would play up for a few mins. Noticed if I put heated screens on the worked fine. I got a put in voltage reader and it was pushing over 16 volts for first couple of minutes then settled around 15 volts. Got a new alternator fitted and all is fine.

Thanks for your replies.

I have used the car over the past couple of days, once started it reads around the 15.2v mark, after 10 or so minutes it drops to 14.4. There is no change in voltage when revving the engine, so I will monitor things for the time being and change the alternator if it gets any worse.

Why - as said it is all normal.

If you had taken the car for a longer drive you would have found that voltage is up around 15v for a short period after start and as you also found then drops away and will come back around 12.5 to 13v depending on battery charge - the alternator is a smart alternator and provides the correct amount of charge to the battery as required - not a steady voltage that may change with changing revs. Higher after start and lower when running. 07MY RRS TDV6
Arctic Frost
Aspen Interior

You may find the regulator rectifier is on the way out. If it's not causing problems leave it alone until it starts to play up with your electrical systems.

As Disco Mikey said:

15,2 Volts is perfectely Normal ( as in absolutely OK )

When just started, especially in Winterconditions,
the voltage will be at 15,1-15,2 Volts for a while.

If You take the car for a spin, lets say about 10-15 miles,
make a brief stop, and restart the engine, You will notice that
the voltage will be around 14,5 Volts, and the next time, maybe 14,1 Volts..

All Ok, standard procedure, no need to change anything.

Here in Sweden, my car gives a steady 15,1-15,2 output fot the first
20-30 minutes, all within the parameters.

The car has lots of stuff that wants electricketry, so the generator has
some serious "deliveries" to make to all hungry customers "online"

Rgds

Uffe As a rule, I always resist temptations,
unless they are irresistible.
My Ride: 2006 RRS HSE TVD6 Java Black/Cherry Woods with HST factoryfitted pack.

Thanks for all your replies. I will take the reader out of the charger socket and enjoy driving the car.

Happy New Year