Good Alternator/battery/starter but no charge?

[rpgvortex]

Hello new to the message board here but looking for some help....... My wife and I bought a rather clean looking 89 t-bird lx, and quickly found that the alternator was not working. we promptly replaced it. But the car still died while driving from draining the battery, I had the new alt. tested again and found that the alt works the (newly charged) battery is good and the starter had just been replaced (we didn't test it as it starts the car when there is juice in the battery). but we are not getting charge still I cut back the wires to the bat. mounts and replaced the mounts all together. still not good... there are two wires from the neg.; one to the engine (have not checked its connection, will in the morning) and one small one grounds to the chasis and then runs through a sensor looking thing and enters a harness and ... Also I can not find a fuse labeled Alternator the largest fuses do not have sizes one is Horn relay? the other is ecc? driving me nuts

[yank with ute]

Did you test the new alternator ON or OFF of the car? If the test was made off the car they may have bypassed the problem.

From first hand experience: The ground straps may LOOK like they are connected but are they in fact physically grounded to the chassis and battery? The alternator won't charge if it is not grounded.

In one of my cases the bolt that was meant to ground the system to the chassis was in fact dangling in air with a part of the body panel attached. Noticed that when I drove home in the early morning that the lights would go out when I depressed the clutch pedal (the ground for the car was working through the light circuit via the pivot shaft for the brake/clutch pedal).

Went to a battery company and was charged for a new regulator. Battery died that night.

Went to Sears and was told once again the regulator was shot/battery won't charge, bought a new battery. The new battery died that night.

Frustrated, I traced the wiring and found the ground was disconnected. So much for "honest" companies in the retail battery business! Neither had checked to see if the battery/charge system were grounded.

Since that time I have bumped into several people who have been finding their battery is discharged in the morning. In every case it was a faulty ground.

Second problem I had only recently is one you should have noticed since you state you cut back the wiring: The retaining nut on the back of the alt that was supposed to secure the charging wire had backed off and in fact the wire/terminal were shorting out against the alt case. The system would charge and then short out draining the battery (was 30 miles from home when I finally noticed the problem).

Tried to tighten the nut but by then it had been arc weled in place and the post snapped. Had to replace the alt I had just installed last year.

But all and all, I'd suggest you check and are certain the system is grounded AT ALL TIMES. It may be a now-and-then problem that is currently in the "now" mode.

Adding more ground straps might solve the problem

[franmosso]

I had the same issue with my 92 Taurus. There was two grounds from the battey, one to the chasis and one to the engine block. The problem was the one to the engine blog was bad. made new connection and all is fine.

[Bowtiebreaker]

Do you have the two pos wires or one. if you have the two hot wires one runs to the starter the other to a box right behind the battery. The alternator hooks to that box. if the wire from there to your alternator is bad you will not get a charge. If the wire from there to your battery is bad you will not get a charge. If you do not have that setup the wires for the alternator can be corroded at the clip that is assuming if you have the three wire alternator. Ground is least important for your engine cranks with no problem.
I 've got a 94 Tbird that had an issue similar to yours. Found loose and corroded connections.

[sek1027]

My husband and I bought a 95 Thunderbird for my nephew and the alternator was making a noise so we brought it to a shop to have it replaced. They have installed 2 alternators and are telling us that the alternators they got are bad because the battery is not keeping its charge. Could we be having the same issue? If they are testing the alternator while its in the car, would it tell them right away if this was a grounding issue?

[BatteryMan]

If you still are having problems after checking the alt, regulator, and grounds; then you need to test to see if the regulator is recieving power at all the right wires on the plug. You shoud have a main battery wire usually orange, or green/red. It should show 12.5v or battery voltage. If you do then run a jumper wire from the battery wire on the plug to the regulator wire on the plug bypassing the regulator. With a volt meter on the battery, you should see the voltage increase if the ALT is good. If this is true then you have a bad regulator, if not probably a bad ALT and should replace both. If you do not recieve power at the regulator plug any where then just follow each wire back and make sure you do not have any bad, loose or dirty connections. They are far more likely on the cars than a bad ground, although that is still a possibility.