car question re: my 91 crx

ondarkness

Platinum Member
Nov 10, 2004
2,003
1
81
the battery light appears while idle at red lights, or stop signs.
It only pops on, and goes away when I rev or by itself sometimes.

I changed the alternator. (I did the pull the ground wire test, and the car turned off)
The battery still comes out though.

Can the battery have been drained and not be holding it's charge?
Or what else could it be?

The car runs fine otherwise.
-other than the occasional electrical whine at startups rather than the engine turning.
-but the second try usually gets it running.

Parking this in the garage.

vi edit
Off Topic Moderator
 

rasczak

Lifer
Jan 29, 2005
10,437
23
81
Originally posted by: ondarkness
the battery light appears while idle at red lights, or stop signs.
It only pops on, and goes away when I rev or by itself sometimes.

I changed the alternator. (I did the pull the ground wire test, and the car turned off)
The battery still comes out though.

Can the battery have been drained and not be holding it's charge?
Or what else could it be?

The car runs fine otherwise.
-other than the occasional electrical whine at startups rather than the engine turning.
-but the second try usually gets it running.

#1 wrong forum
#2 take said battery to autozone and tested.
 

mh47g

Senior member
May 25, 2007
741
0
0
Your alternator is bad (or better way to say it is, it's not your battery)

Edit: Your battery light will ONLY come on while the car is running if your alternator is not supplying juice. Even if your battery is bad while your car is running, the light should not come on if you have a good alternator.

Your belt might be slipping, or...?
 

ondarkness

Platinum Member
Nov 10, 2004
2,003
1
81
the rpms are jumpy a little over 1000
im thinking the belt might be loose, as it was my 1st time changing an alternator.
the alternator was refurbished too, so that might be it.
any way to check if it's the refurbd alternator?
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
44
91
Originally posted by: ondarkness
the rpms are jumpy a little over 1000
im thinking the belt might be loose, as it was my 1st time changing an alternator.
the alternator was refurbished too, so that might be it.
any way to check if it's the refurbd alternator?

At idle, you should be getting ~13.5 volts across the battery terminals. to do this properly, you need a load tester, but a quick check with a multi-meter can tell you if it's really bad. Places like AutoZone should have tools to load test a battery that you can borrow.

ZV
 

ondarkness

Platinum Member
Nov 10, 2004
2,003
1
81
good tips guys.

-will check the load, the current charge, and into changing the cables.
When I bought the rex, it had the battery relocated to behind the pass seat, so thats another factor.

thanks!
This forum is like the big brother I never had
=)
 

HiTek21

Diamond Member
Jul 4, 2002
4,391
1
0
My dads Tacoma had a battery light on. We replaced the alternator and it was still on. Turned out theres a signal wire somewhere from the alternator to the gauge that broke causing the light to stay on.