Charging System

Topic: Charging System (Read 5565 times) previous topic - next topic

Charging System

Reply #15 – November 19, 2016, 10:12:59 PM

Unplug the regulator connector on the alternator.
Check for battery voltage on the yellow wire with the engine off.
Turn the key on, don't start the engine. Check for voltage on the green wire.

Charging System

Reply #16 – November 19, 2016, 11:26:34 PM

Confirmed, 12.5 volts on the yellow wire with the key off.
However, only 0.5volts on the green one with key on, engine off.

So what does that mean?

-Kyle

Charging System

Reply #17 – November 19, 2016, 11:50:13 PM

Quote from: kylesburrell;458068

Confirmed, 12.5 volts on the yellow wire with the key off.
However, only 0.5volts on the green one with key on, engine off.

So what does that mean?

-Kyle

No battery voltage on the green wire with the key on is your problem.

What was the car originally? Year, engine and instrument cluster?

If you have changed the cluster. what is the cluster from?
Is the original cable harness and connectors still in the car?
Do you have the instructions used to change the cluster?

Charging System

Reply #18 – November 19, 2016, 11:58:41 PM

originally 1986 tbird elan 5.0, AOD, this cluster was replaced years ago cuz the original one from 86 failed. Ive also put LED 914 bulbs in said cluster to help with illumination

I havent messed with the wiring since last fall. So thats why I thought it was weird that it is acting up NOW.

-Kyle

Charging System

Reply #19 – November 20, 2016, 12:18:19 AM

Does the red battery light turn on? This is the wire that turn on the alternator. There should be a resistor on that wire somewhere in case the light bulb burns out. You essentially bypassed the bulb by putting in led. Leds are light emitting diodes, they stop power from flowing one direction. Could be as simple as an led being installed backwards. Try a regular 194 bulb.

Charging System

Reply #20 – November 20, 2016, 12:27:22 AM

Voltage on the green wire is required to signal the voltage regulator to turn on the alternator.

I am pretty sure the stock 86 5.0L had a alternator warning light on the cluster. The keyed voltage for the green wire to the regulator comes through the warning
light bulb and it's parallel resister.
Was the cluster replaced with a stock 86 cluster or something else? Did you do the job?

How come the problem is just showing up now if it started with the cluster change?
If you don't drive it much, you could have been running on the battery.
Or, some times these alternators can turn themselves on if they have enough residual magnetism and you rev them up high enough.

Charging System

Reply #21 – November 20, 2016, 12:39:20 AM

Quote from: Haystack;458071

Does the red battery light turn on? This is the wire that turn on the alternator. There should be a resistor on that wire somewhere in case the light bulb burns out. You essentially bypassed the bulb by putting in led. Leds are light emitting diodes, they stop power from flowing one direction. Could be as simple as an led being installed backwards. Try a regular 194 bulb.

Good thought haystack. I thought I was the only one who stayed up this late.

Charging System

Reply #22 – November 20, 2016, 01:05:58 AM

Quote from: Haystack;458071

Does the red battery light turn on? This is the wire that turn on the alternator. There should be a resistor on that wire somewhere in case the light bulb burns out. You essentially bypassed the bulb by putting in led. Leds are light emitting diodes, they stop power from flowing one direction. Could be as simple as an led being installed backwards. Try a regular 194 bulb.

So with the key on, the red E-brake light comes on, as well as the red "fasten seatbelt" light. I should clarify: when I put in the LED 194 bulbs, I only put them behind the 3 main modules, the green digital displays in the cluster

Charging System

Reply #23 – November 20, 2016, 01:10:08 AM

Quote from: softtouch;458072

Voltage on the green wire is required to signal the voltage regulator to turn on the alternator.

I am pretty sure the stock 86 5.0L had a alternator warning light on the cluster. The keyed voltage for the green wire to the regulator comes through the warning
light bulb and it's parallel resister.
Was the cluster replaced with a stock 86 cluster or something else? Did you do the job?

How come the problem is just showing up now if it started with the cluster change?
If you don't drive it much, you could have been running on the battery.
Or, some times these alternators can turn themselves on if they have enough residual magnetism and you rev them up high enough.

the cluster came from a similar year lincoln i think. But again, the cluster was replaced 3 years ago. Yes i installed it, I didnt trust anyone else to take it apart and not break the 30yr old plastic.
And I do usually drive the tbird, just havent recently, have had 2 brake issues in the last several months. And I have a truck, so i never HAVE to fix the tbird.

Charging System

Reply #24 – November 20, 2016, 01:36:00 AM

Check the ignition switch. From memory, it pretty much run straight through the ignition switch to the red battery light turn on to the alt. I think you have it narrowed down pretty good.

Try putting a jumper to the green wire under the hood and see if ya can send 12 volts to make it turn on, this will guarantee that its in this part of the system.

Oh, and im not up that late... Im mst so it was only 10:30pm when I posted.

Charging System

Reply #25 – November 20, 2016, 03:51:21 AM

What you have is a common problem people have when they swap in a cluster that does not have an alternator warning light.
The fix is to find the green/red stripe wire on one of the cluster connectors. Cut it and splice it to the gray/yellow stripe keyed power wire.
Some people are more comfortable connecting the wires through a 500 ohm resister, rather that a direct connection.
I personally am not convinced it makes any difference.

If you find the green/red wire on pin 4, the gray/yellow wire will be on pin 6.
If you find the green/red wire on pin 10, the gray/yellow wire will be on pin 11.

Charging System

Reply #26 – November 20, 2016, 05:22:23 AM

Do you sit with an EVTM in your lap?

Charging System

Reply #27 – November 20, 2016, 09:59:15 AM

Quote from: Tbird232ci;458089

Do you sit with an EVTM in your lap?

we have a few years scanned and up on various cloud locations as well.

Charging System

Reply #28 – November 20, 2016, 11:47:09 AM

Quote from: softtouch;458080

Some people are more comfortable connecting the wires through a 500 ohm resister, rather that a direct connection.
I personally am not convinced it makes any difference.

I'm in favor of some sort of current limiting, at least with resistor wiring won't likely burn in main harness if there is a short to ground at alt... Doesn't have to be 500 ohms, circuit is stupid works just as well with anything between probably 100 & 500 ohms... If bulb is used, parallel resistor should be included in case lamp burns out, that requires a fairly high value resistor as lamp will be dim with a low value... Old stuff with mechanical regulator generally used 15 ohms in this position but had to pull in relay contact...

Charging System

Reply #29 – November 20, 2016, 11:55:54 AM

Quote from: softtouch;458080

What you have is a common problem people have when they swap in a cluster that does not have an alternator warning light.
The fix is to find the green/red stripe wire on one of the cluster connectors. Cut it and splice it to the gray/yellow stripe keyed power wire.
Some people are more comfortable connecting the wires through a 500 ohm resister, rather that a direct connection.
I personally am not convinced it makes any difference.

If you find the green/red wire on pin 4, the gray/yellow wire will be on pin 6.
If you find the green/red wire on pin 10, the gray/yellow wire will be on pin 11.

Hmmm, im really impressed with how knowledgeable you are. So just add a resistor to bridge green/red stripe wire AND gray/yellowstripe wire.

And, how have I been driving the car like this for 3 years? I might also check my crimp connections for the 3G alt. wiring.