Fox T-Bird/Cougar Forums

Technical => Electrical Tech => Topic started by: chach868 on November 19, 2015, 11:31:36 PM

Title: T-Bird's Not Charging....
Post by: chach868 on November 19, 2015, 11:31:36 PM
Hey guys, its been a while....

I was on my way home when the interior lights dimmed, radio died, and I eventual found myself on the side of the road waiting for a tow.  I have a fairly new battery and alternator, but just to be safe, i switched out my alternator and voltage regulator.  Exact same problem.  I used a probe to check all of the various connections, and cant figure it out for the life of me.  I got the alternator bench tested, and plan on exchanging the volt. regulator tomorrow but i seriously doubt thats the problem.  Any suggestions? Im stumped!!!
Title: T-Bird's Not Charging....
Post by: Haystack on November 20, 2015, 12:13:46 AM
What year and motor? If it's a 86-88 5.0, soft touch just posted the wiring diagram in another thread.
Title: T-Bird's Not Charging....
Post by: Haystack on November 20, 2015, 12:16:03 AM
http://www.foxtbirdcougarforums.com/showthread.php?39292-test-attachments

Here is the 86-88 302.
Title: T-Bird's Not Charging....
Post by: chach868 on November 20, 2015, 12:36:44 AM
Thanks so much, but I have all the factory manuals, and cant figure out the problem.  My motors a 2.3 turbo.  No dash indicator for the alt.  (I port on the volt regulator).  Any other common problems or a way to trace the issue?
Title: T-Bird's Not Charging....
Post by: Haystack on November 20, 2015, 12:48:10 AM
Give me a bit, I'm looking up a 2.3 alt diagram now.
Title: T-Bird's Not Charging....
Post by: Haystack on November 20, 2015, 01:02:42 AM
There are 3-4 different 2.3 alt setups supposedly. Outside of fuseable links, replacing the alt and regulator should fix the problem.

I had an alt go bad on me, I had to have them test it 3-4 times before it actually failed.
Title: T-Bird's Not Charging....
Post by: softtouch on November 20, 2015, 01:11:36 AM
The 86 EVTM shows the 2.3 Turbo has a 1G alternator and external regulator.
Title: T-Bird's Not Charging....
Post by: Haystack on November 20, 2015, 01:40:21 AM
http://www.foxtbirdcougarforums.com/showthread.php?38176-Problem-with-anti-theft-system-(I-think)-please-help!!!

I was looking for this thread, and it turns out it was your car lol.

I had a few weird things with the car running and charging, kept getting a battery light while driving and the car shut off. I threw in a new ignition switch and while I was there I found my problem. A few of the wires were loose and needed to be recrimped in the connectors. After that, I had no more issue. I wonder if your problem could be the same? My 86 does have almost 300k more miles then yours though...
Title: T-Bird's Not Charging....
Post by: chach868 on November 20, 2015, 02:26:14 AM
..... Im super confused.  I didnt realize that it was you that solved my previous problem. I am still indebted. Hmmmm maybe ill check out the switch again. hell if its under warrantee, maybe ill switch it out.
Title: T-Bird's Not Charging....
Post by: Haystack on November 20, 2015, 04:37:31 AM
I didn't fix your let problem. Like 5 other people jumped in first and said ignition switch.

I ment to check the plug side of the ignition switch. It looked like to me it was just crimped fittings and they can come loose. Several connections have two wires feeding them and one could easily come loose. Im going by memory though, think its been close to 4 years since i had mine apart.

When you had the alt tested good, how many times did they do the test? Like i said earlier, it took 3-4 times to get mine to fail last time.
Title: T-Bird's Not Charging....
Post by: chach868 on November 20, 2015, 02:38:47 PM
Ok, so I bought a new alt and volt reg. when the car died; same problem.  So when i went back to the store, I brought both alt.s and had my Original alt. tested 3 times.  It passed all three times, so i returned the new alt. and volt. reg. and am about to go pick up a new volt reg. and give it a shot, if its not that......im confused.  I tested the fuses and am not even sure which fuse would effect the charging system the way it is.  I suppose it could also be one of the fusable links.  Hell, who am I kidding? I havent the slightest idea....
Title: T-Bird's Not Charging....
Post by: TurboCoupe50 on November 20, 2015, 04:00:02 PM
Quote from: chach868;452451
  I suppose it could also be one of the fusable links.  Hell, who am I kidding? I havent the slightest idea....


OK you said you have the manuals, look at page 22 in the EVTM, fuse link A is most likely open, connects between S131 & S132... Next look at page 32, states fuse link A is near starter relay(several others as well)... Fastest way to test is pull on link(s), if it bad will stretch easily... OR you could use real troubleshooting and test to see if there voltage on terminal A of the voltage regulator and on battery(largest wire) terminal of alt... With engine OFF, lack of voltage on both indicates fuse link A is open...
Title: T-Bird's Not Charging....
Post by: chach868 on November 20, 2015, 04:03:03 PM
alright, I'll go check it out right now.  As of now i just jumped the car with a tested alternator and a new volt. reg, same problem.  This leads me to believe that the problem lie in neither component.  The strange part is that the car started fine when I was heading home and just randomly died on the freeway.....  Ill check the books.  thanks man, your flock of t-birds makes me jealous.
Title: T-Bird's Not Charging....
Post by: softtouch on November 20, 2015, 04:08:10 PM
Quote from: TurboCoupe50;452452
OK you said you have the manuals, look at page 22 in the EVTM, fuse link A is most likely open, connects between S131 & S132... Next look at page 32, states fuse link A is near starter relay(several others as well)... Fastest way to test is pull on link(s), if it bad will stretch easily... OR you could use real troubleshooting and test to see if there voltage on terminal A of the voltage regulator and on battery(largest wire) terminal of alt... With engine OFF, lack of voltage on both indicates fuse link A is open...

And after you make those voltage checks, turn the key to RUN (don't start the engine) and check for voltage on the S terminal of the regulator.

In the 3.8 and 5.0 cars with the alternator warning light, after the Alt starts turning and has an output voltage, it keeps itself turned on. This done with a wire from the Alt S terminal to the regulator S terminal.
In your case, the ignition switch wire goes to the regulator S terminal.
Title: T-Bird's Not Charging....
Post by: chach868 on November 20, 2015, 04:14:56 PM
Quote from: softtouch;452454
And after you make those voltage checks, turn the key to RUN (don't start the engine) and check for voltage on the S terminal of the regulator.

do you mean S on the harness? how do i test the reg. with it plugged in?
Title: T-Bird's Not Charging....
Post by: softtouch on November 20, 2015, 04:42:49 PM
Quote from: chach868;452455
do you mean S on the harness? how do i test the reg. with it plugged in?
I don't remember if the harness connector is labeled with the terminal letters or not. It will be the LG/R wire on the S terminal.
Are you looking at page 22 of your EVTM?
You can try back probing where the wire enters the connector.
With a test light that has a sharp probe, you can pierce the wire insulation.
You can unplug the connector. Recommend disconnecting the negative battery cable while unplugging and plugging the connector.
Title: T-Bird's Not Charging....
Post by: chach868 on November 20, 2015, 05:06:31 PM
ok.  Well i know where the fusable link is. it doesnt feel too squishy, but i cant think of a problem other than this, now that ive basically gone through the whole system.  I ran some basic diagnostics on the wires when my buddy was here with a power probe, but ill have to wait for him to come back to finish testing everything.  that diagram was super helpful thanks.  The volt. reg. is labeled as well..... ill give this all a go as soon as i have access to the proper tools....and I'll post results.....thanks a ton.
Title: T-Bird's Not Charging....
Post by: softtouch on November 20, 2015, 05:17:13 PM
Here is an old school no fancy tools test.
With a screwdriver, feel around the alternator case for a difference in magnetism between key off and key in run. (don't start the engine)
Title: T-Bird's Not Charging....
Post by: chach868 on November 20, 2015, 06:33:08 PM
i am positive that the alternator is not charging. with the car running it only puts off 8 volts.  just trying to figure out where the drain is.
Title: T-Bird's Not Charging....
Post by: softtouch on November 20, 2015, 07:00:02 PM
Quote from: chach868;452460
i am positive that the alternator is not charging. with the car running it only puts off 8 volts.  just trying to figure out where the drain is.
Is this measured at the battery terminals?
What does it read with the engine not running?

Sounds like a battery with 2 dead cells.
Title: T-Bird's Not Charging....
Post by: chach868 on November 25, 2015, 03:25:21 PM
the battery is fine, i guess im going to take a shot at the fusable links today.  I suck with electrical so wish me luck!  I'll be back on when I figure out what is going on
Title: T-Bird's Not Charging....
Post by: Haystack on November 25, 2015, 04:13:27 PM
Fuseable links are easy. Just probe the wire before and after and do a resistance check.
Title: T-Bird's Not Charging....
Post by: chach868 on February 29, 2016, 11:20:51 PM
alright, so sorry for taking so long to get back to ya guys..... it ended up being a regular old fuse under the dash.  I tested em but apparently missed one.  thanks for all the help.