Alternator not charging, battery and alternator are good.
 

Okay here is the run down. My inertia fuel switch in my maf sensor went bad in my fc causing me to burn up the starter. The wire from the starter to the solenoid was completely burnt. So I got a new starter and put it on, and also wired a 30 amp toggle to the fuel pump which is running off a 20 amp spare in the fuse block.

Well my problem now is that the alternator isnt charging the battery. both the battery and alternator are good. Even swapped out the alternator with a new working one, still happening. All grounds are secure.

Please help.

S4 or S5? NA or turbo? I can't tell you much about the fuel toggle, but I would say that's a good place to start. Have you attempted to do without the toggle since replacing the starter? Also did you replace the MAF? Because if you didn't, it's probably toast.

What is the voltage output of the alternator would be some important info to share. And how would a switch in the AFM burn out your starter??????????

Its a s4 non turbo 5 speed. i have the fuel pump toggled due to the maf not sending the signal to the fuel pump due to the fuel switch that isnt working thats inside the maf.

the voltage output isnt a steady voltage. after i jump the car it goes from 14 down to around 9 volts and its kind of a gradual decrease. but goes pretty fast.

Tried a new working alternator and it done the same thing so i ruled out the alternator.

Hmmm. Why not just replace the AFM and the MAF to start? I still don't understand why that would even remotely affect your starter, but if you know there is a problem in it, you need to replace it.

it didnt affect my starter. it went out so i wasnt getting fuel and didnt know it and kept cranking and burnt my starter up. im wondering if the maf would be drawing down the power or not.

You have a plug w/two wires that connects to the back of the alternator. Top wire is Black/White and the bottom wire is White/Black. Do you have this plug connected to the alternator? Are you sure the alternator pulley is at the proper tension, not too tight nor too loose? And the AFM will not affect the alternators output but the starter would. And jumpering the fuel check connector will bypass the broken fuel switch found inside the AFM so there is no reason to toggle the fuel pump at all.

well i didnt know if it would run correctly off of the plug if i jumpered it. it would be the same as grounding out the brown wire to the maf so i may try it and take the toggle off and put it on the signal wire so i can still cut the fuel when starting to prevent flooding.

the plug that went to the alternator looked burnt up so i cut the plug and put connectors on the wires and plugged em back up correctly on the alt. they arent touching each other either.

The two wires on the back must have the proper voltage and again, the B/W wire is on top and the W/B goes to the bottom pin and of course the wires need to be making a proper connection and perhaps maybe this is your problem. W/key to on both of these wires will have 12 volts w/the plug disconnected from the alternator. W/the plug connected the voltage on the W/B wire drops to 2 volts or so w/key to on while the B/W wire stays the same. W/the engine running both wires will have 12 volts to them. And make sure the large voltage output wire is mated properly to the alternator and w/the car running use this output wire to get an accurate voltage reading instead of relying on the voltage gauge in the instrument cluster.

Yeah the wires are showing correct voltage and are in the right spot. ill try jumping the plug once i get home from work and see if that helps. if not then i think i got a short somewhere. all my grounds are fine, secured and not dirty or anything.

The alternator will self excite itself if you rev the engine above 4 to 5k and if the voltage returns to normal levels then either the alternator is no good or the wiring is just not right. And alternators can test well outside of a car but not when installed and this occurs rather regularly w/cheap aftermarket replacements. One thing you can try is to disconnect the output wire from the alternator and read the output from the alternator terminal and see if there is a difference. And when replacing the starter are you certain you reconected it properly w/respect to the wiring that comes from the battery (positive and negative cables)?

I've tried to excite the alternator and it didnt work, and like I said before i swapped it out with a working one and it done the same thing. I reconnected everything properly when i put the starter on.

could it be a possibility that my battery is bad? or would that even effect the way the alternator works? Im not 100% on how the charging system works on the s4 fc's.

It might affect it, but if you disconnect the output wire from the alternator and test the alternator output from the alternator terminal that will tell you if the problem is caused by the alternator itself or some outside source.

ive tried with the output wire on and the voltage was decreasing the same amount as the battery.

With it off, with it off.

okay, ill try it.

With the output wire off it was showing 17volts while running

It should peak at 14.4 volts. Apparently the voltage regulator is not doing its job.

EDIT: You might want to reconnect the output wire then start the car up then disconnect the battery and then test the output of the alternator.

Thanks satch. I found the problem. If I take the ground terminal off it runs fine and charges. So I have aa bad ground.

Post a pic of that "ground terminal" will ya.

It has brand new terminals on it.

..and WHAT has brand new terminals on IT?..the harness,the battery cables,the alternator?
You say you took the ground terminal off and it runs OK now,So take a pic of the terminal you took off and post it.
I'm curious as to what you did and the only way to get that answered is with a pic.Your explanations..frankly lack any info.(sorry)..

The battery has brand new terminals on it. i took the negative terminal off of the battery while running and it ran fine.

would that mean i have a bad ground, my battery is shot, or what?

Could be or the negative cable from the battery which runs to the ground at the fender is poor and then the cable after passing through this ground point continues on to the starter and that might be going to the wrong connection as it should be going to the long mounting bolt of the starter.

well i have the starter hooked up properly. the ground is going to the bolt that doesnt have the wire connected to it.

Pic of the starter in the link at post #40. This pic illustrates an incorrect starter so take this into account. Notice the triangular flange of the starter which has the hole through it? This is where the ground wire goes. And read the next post, post #41 as well.

https://www.rx7club.com/2nd-generati...-932163/page2/

i believe i only have one thick wire going to the starter. Not two. ill check when i get home and take a pic and upload it.

You must have two, both are from the battery. The one w/the Yellow stripe is the ground and goes to the triangular part which mounts the starter to the transmission. This is how the circuit is grounded to the car. The other cable is the positive wire from the battery.

yea i messed up. i have the ground going to the post on the starter. thats my problem. i have 2 wires but ones the thick black and yellow and the other is the small power wire.

But how would the car stilll be starting up if i got it wired incorrectly?

The more important aspect should be if you don't have it wired properly then how do you go about in rectifying the situation as opposed to anything else because under the current scenario your car is not operating properly. As already stated, the negative ground cable off of the battery runs to a grounding block at the driver's side fender. Additionally, the starter grounds to the transmission housing.

Im so confused, and cant find a picture of one hooked up the correct way either.

All you have to do is read post #41 in the link provided and that's all you need to know and nothing else. Nothing.

I have 3 wires. Two are skinny. One of em has the connector for the starter. Other has a eyelet eith a black box on it. The large wire is all black and is a positive wire. So is the skinny wire with the black box a ground?

Like in post #1, first pic?

https://www.rx7club.com/2nd-generati...d-help-851629/

If so then it is a condenser and is not starter related. For the umpteenth time, the negative ground wire goes from the battery to the driver's side fender grounding block and then on to the starter's mounting spot. You need to follow this cable down frrom the battery to the grounding block and then down to the starter. I mean we're talking about a whole five feet or so of wire. You need to figure it out for yourself.

Yupp that one. The eyelet just broke tho. It was a signal wire tho.

I've followed it. It just goes to the trans.

The battery cable is like Rope size.
that little wire with the black chunk of hash on it is spaghetti size and has Zilch to do with the starting system.

If you look at the pic once again for the starter it has a triangular portion at the end of it in which the long mounting bolt goes through it. This is where the ground goes. It does not go to any other spot. The starter mounts to the transmission so the ground gets sandwiched between the two.

EDIT: And have you examined the negative battery clamp you recently installed? It should be soldered to the cable. Make sure it is up to square.

The eyelet chip thingy is for the Oil Sender and is normally bolted to the slave cylinder but the wire itself should not be grounded to anything or the oil gauge will say "I'm not working any more." Just tape it off as it is rather useless.

Well I added a 6 gauge wire from the battery to the mounting spot and it helps but I'm still getting a draw. Ill searchmore ttomorrow for the wire.

And in the process clean up the grounding block at the fender and redo the terminal clamp at the battery (both of them).

Ill do that as well. I also swapped the toggle out and just hooked the signal wire back together and jumped the bypass connector. Running at 12 volts. All accessories off. 11 volts with accessories on. Battery was still being charged by the alternator I assume. But when I cut the power I couldn't start it back up without a jump.