Issue with alternator/headlights

[yUBER]

Issue with alternator/headlights

So my r32 gtst is having this problem where my car batteries would die the next day so i changed the car batteries 3 times and the problem persist. I figured maybe it was my alternator so i got a multi-meter and tested it the numbers coming in were in the normal ranges. I tried all the load test and they came back normal but the one thing i noticed was when i had my headlights on and i revved the car the voltages would drop on the meter down to not so normal ranges around 12 volts. On idle everything is normal but when i rev up the car around 1500-2000 it goes down only when headlights are on any idea what could be the problem?

[admS15]

The alternator is on its way out.

[89CAL]

Why say "I got normal numbers"? wouldnt it make more sense to give actual voltage readings? not trying to be rude but perhaps they are not normal numbers.

It sounds like the altenator is not able to keep up with high load, so above statement is possibly correct. More info needed

[tridentt150v]

flux capacitor needs replacing...lol

Take the alternator out and get it checked by an auto sparkie shop....they have the best test rigs for this and generally they will test for nothing or at worst nominal cost.

[yUBER]

Sorry i assumed people would know what normal voltage readings is if they knew about what i was talking about lol. The voltage reading is around 13.90v-14.30v on idle no load with load 14.11v - 1370v with headlights on only it idles about the same but when revving the engine it drops too around 12.38v. Probably is the alternator thanks for the quick response.

[Missileman]

could also be loose connection or a bad earth

[blind_elk]

Could also be a loose fanbelt. Or a dying fanbelt.

[niZmO_Man]

Replace the negative terminal earth strap with something bigger.

[Robzilla32]

  On 04/03/2017 at 3:51 AM, niZmO_Man said:

Replace the negative terminal earth strap with something bigger.

This - you haven't installed an amp recently? Probably obvious but I did this recently and the battery was draining super quick.

[yUBER]

Sorry for the noob question but what exactly do you mean by bigger? as in the size of the strap?

[89CAL]

I would say he is talking about thicker gauge wire yes

[niZmO_Man]

  On 04/03/2017 at 8:33 AM, Robzilla32 said:

This - you haven't installed an amp recently? Probably obvious but I did this recently and the battery was draining super quick.

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I was actually trying to diagnose issues with HICAS, upping the earth strap definitely helped. But yes I have an amp (two actually haha).