Low voltage at low revs

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Jamie
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Low voltage at low revs

Post by Jamie »

Just replaced my alternator on R50 Terrano with brand new item. Not genuine however. Dash lights and heaters dip in power when at idle. Voltage returns as revs lift. What is the problem here?
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kbushnz
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Re: Low voltage at low revs

Post by kbushnz »

Dud alternator...
Cheers Calvin
KZJ78 Landcruiser Prado...
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Mattman
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Re: Low voltage at low revs

Post by Mattman »

Bust out your multi meter and check the voltage and idle. As above possibly a dud. Rather than getting a repo you are often better off rebuilding your existing alternator.

Matt.
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evolution02
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Re: Low voltage at low revs

Post by evolution02 »

Probably normal, need to get a volt meter and check voltages
Alternator output depends on engine revs. So wont have much output at idle and with the lights and heater voltage will go down.
You need to check with a volt meter.
slidenyo
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Re: Low voltage at low revs

Post by slidenyo »

are all the wires hooked to the same spots,
some alternators need a signal wire to let them know when to start charging/regulating to 12volt
problems are only a problem if you not willing to learn how to find solutions
ChurchurDan
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Re: Low voltage at low revs

Post by ChurchurDan »

Check it with the engine warm. The after glow on these stays on for a while when first started and really draws some power. When warm the voltage should be 14-14.5 at about 1000 rpm with every thing turned on, if it cant do that its a dud.
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