My car died (alternator has been weakening..now crapped out earlier today) & I replaced the alternator. I jump started the car after I replaced the alternator & it fired right up. The voltage level (according to the car gauge) was dead in the center of the "R" in "NORMAL" on the gauge.. normally it's on the "N" or "O".
The problem is... the battery symbol (MIL) is illuminated (red). It is not going away at all. I tried disconnecting the battery ground cable for 25 mins to reset the computer, but this didn't work. It holds a good charge, but the light will not go away. I checked all fuses & none are blown. Any thoughts?
A inexpensive thing to do would be to run down to the local Radio Shack and pick up a $5-$10 DMM (digital multi meter). It's hard to diagnose anything through a computer with out at least a modicum of information.
...Ron
--
68' Camaro RS
88' Firebird Formula
00' Mustang GT Vert
I went to Autozone because my buddy is a manager there & he brought out the battery tester... it's apparently in extremely good condition, EXCEPT at idle with headlights on & A/C going full blast... it's drawing about 4-5 amps (-4 to -5 displayed). I snipped the battery cables & re-connected them to the terminals with new battery terminal connectors... didn't help. I cleaned the battery terminals as well. I also tightened all connections w/ the alternator (which was just 1... the power wire..).
Any thoughts? This stinkin' red battery light remains illuminated.
On Fri, 29 Jul 2005 17:24:35 -0700, snipped-for-privacy@cellulean.com rearranged some electrons to form:
Apparently, your alternator is not supplying enough current to charge the battery and run the electrical accessories.You really need to measure the output voltage... why didn't your Autozone buddy measure it?
So you're thinking the alternator could be at fault? I'll go to Hammons Auto Parts first thing Monday (where I bought it) and let them test it. Grrr.. what a pain in the ass =(.
On Sat, 30 Jul 2005 03:43:17 -0700, snipped-for-privacy@cellulean.com rearranged some electrons to form:
An alternator works by creating a rotating magnetic field which cuts across a set of wire windings. As Mr. Faraday and Mr. Maxwell told us, a changing magnetic field intersecting ith a wire creates a current in the wire. Since the field is rotating, the current alternates between positive and negative and thus creats alternating current (AC). Strategically placed diodes forces the current to go in the same direction, thus creating direct current (DC).
The rotating field is created as DC current from the battery flows through slip rings to a field winding on a rotor that is spun by the belt pulley.
Some time ago I disassembled the alt. on my Torino and installed a "hi-output" kit.. new brushes, different stator winding, and some bigger diodes. If I am at a slow idle (stopped at a stop light whilst still in drive), the alternator output will drop enough that the voltmeter drops below 13 volts. The regulator leaks enough current through the ALT light to turn it on just barely in that case. Goosing the throttle makes it go back to normal.
The regulator is trying to put enough field current through the rotor to keep the voltage up at low RPM. When it hits the maximum current, the output voltage drops and the light comes on. The OEM style regulator was only able to vary the field current discretely, it had a relay inside that basically turn the field on and off to maintain the output voltage. An electronic regulator (which I have now) can vary it across the range of adjustment.
Guess what, 35 years later, alternators still work the same way, except now the regulator is built into the unit. I would take the unit back and have it tested. I haven't ever had too much luck with generic auto parts stores alternators, they don't really last very long. I would try NAPA.
Also, it's possible that they didn't hook it up right....
Well, he hooked it up to the battery... and tested both, but I want Hammons to specifically test the alternator when it's removed from the car. I figure they could do a more thorough examination, no? I dunno. I might just try to get a refund from them & get an alternator from a more "recognized" establishment.. like local NAPA store.
Many alternators can't run the AC full blast and the lights at an idle. A lot depends on the design of the charging system. The real question is not what the battery voltage is, but what would a similar car with a good charging system do under the same conditions. A car with an engine that pulls a lot of RPM has the have the alternator "geared" to not exceed its RPM limit. At idle that alternator will turn slower. Like when you install a pulley kit.
David M wrote in news:pan.2005.08.01.19.51.01.220785@sled351:
Pulleys killed my LX. I was going through a battery every 10-12 months, and the thing was never charging unless it was turning at least 1500 rpm. And that's not mentioning the overheating problems in the summer.
Put the stock pulleys back on and everything's great.
Joe Calypso Green '93 5.0 LX AOD hatch with a few goodies Black '03 Dakota 5.9 R/T CC
Stock pulleys are on. I never had much interest in underdrive pulleys.
The battery light stays illuminated ALL the time..not just at idle. I want that light GONE.. don't want to hafta replace the battery every few months. It's drawing power from battery at idle with headlights on & A/C full blast... and that's the only time, but still... it's a pet peeve at least & that's enough to make me replace the alternator w/ a better one.
" snipped-for-privacy@cellulean.com" wrote in news: snipped-for-privacy@z14g2000cwz.googlegroups.com:
pulleys.
Mike, you've got a problem somewhere if that light's lit all the time. Double-check the alt, maybe get another replacement. Check the wiring leading up to the alt also. HTH.
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