GEN cluster lamp stays ON with ignition OFF

Hello everybody!
After plugging everything together have a little electrical disaster

All wiring is stock, with some wires repaired or changed to new pieces
especially under the hood. The full story is:

I (as I thought) plug in all pigtails/plugs inside the cabin, and under the hood. Battery connected. Ignition key in 1st position (GEN OIL lamps ON). Turn ignintion key in 2nd position (GEN OIL lamps off, TEMP lamp blinking) engine starts, all lights cluster idiot lights out. Everybody think everything is ok. Testing battery charging with alternator - no charge. Alternator pulley getting extremely hot after a minute of work (don't know why, all pulley's are lined). After making some research there is no "+" on alternator wire in plastic plug (wire that goes to lamp GEN in cluster, pin #13). After making straight wire to alternator's plug from wipers motor "+" everything works and battery is on charge.

Making further reseach and wire that doesn't have "+" in alternator's plug is going to pin #13 in cluster, than to GEN lamp and exit at pin #14. From cluster pin #14 pink wire goes to several places.
Further wiring research in the cabin I noticed two disconnected pigtails inside the cabin, first (it contains brown and this cluster #14 pin). Steve Mcarlo77 noticed that my plug has pink wire and his wiring doesn't. But I think it's made so from factory. New black tape is mine.


and second



I tried to find where else I can plug in male pigtail but found nothing else except female that are on photos. From this female pigtail two yellow wires are going under hood, one to blower switch, second as I understand to blower relay.


So, I connected that male to female and what we have now - Battery is connected to system, ignition key position 0 (off), and GEN lapm is always ON.

The main idea is that everything in car worked well before frame off, except blower lower and middle speeds, as I remember. So everything must work ok or in the same way after connecting all males/females.

I guess now something gives a straight "+" on this pink wire (pin #14) from junction on the firewall via heater relay and lights on the GEN lamp when ignition is off. This pink wire must have constant "+" signal only in 1 key position not always if I'm thinking right.
I think the only place where I could confuse wiring pins is heater relay or alternator plug. My heater relay has 5 pins, 2 for join female pigtail and 3 separate pins.



Are there any other relays in car that can control GEN lamp and
alternator? I can recognize only one this blower relay.

I will dig in wiring more this weekend but may be somebody had similar problem or knows where to dig in first.

Alternator is checked and is OK.

Thank you for help!

Forgot one more thing, when engine ran and battery wasn't charging GEN lamp didn't turn ON

We just discussed this in another thread not long ago, so it's still pretty fresh in my mind.  The PNK and BRN wire connector does connect to the double YEL wire.  The BRN is the + feed from the HVAC fuse , and it feeds all three of the other wires: the YEL wires feed the HVAC circuits, and the PNK wire runs to the GEN light.  On the other side of the GEN light is a BRN wire that runs to both the ignition switch and the alternator itself, which are the only two things that should be able to turn on the light.

So diagram #2 is little off: in the middle of the BRN wire running from the fuse to the controls you'd have to put a splice, then from the splice the two YEL wires leading to the controls and the PNK running to the the PNK in diagram #1.

The way the circuit works for the GEN light is that if the ignition is on, there is 12v + coming down the first BRN wire to the PNK wire and then to the light.  The ignition switch in position 1 (lamp test) grounds the BRN wire from the lamp, completing the circuit, and the bulb lights up as a test.  In the run position, though, the ground from the ignition switch is disconnected, the lamp goes off, and the alternator is in control.  If it senses a problem, it grounds the BRN wire itself and the lamp lights up because the juice now flows from the lamp to the alternator ground.

So, assuming all the wires are run correctly, if the GEN lamp is on when the ignition is off, the first BRN wire (the one that comes from the fuse and directly splices to the PNK at the connector) has 12V when it shouldn't.  To verify, connect a meter from that BRN/PNK connector to ground.  There should only be 12v when the ignition switch is on.  If there's 12v when the ignition is off, there's probably an issue with the ignition switch itself or the wires feeding from it to the fuse box.

Thank you very much for the answer!
Like this?


Your theory about constant "+" at BRN wire will work if not mentioning one thing: that if I disconnect this plug as it was when I first start the engine (BRN/PNK to YEL/YEL) GEN lamp will be out while engine runs and battery NOT charging. So I think it's not BRN wire who's guilty.

Can somehow "+" signal сome to GEN lamp not using BRN wire at all but using these two YEL wires? For example Blower relay has constant "+" from junction on the firewall near the booster. Can "+" get to GEN lamp from junction if wires on blower relay are confused somehow?

And if engine runs, GEN lamp is off, and there is no charge on battery... wires on alternators plug can be confused??

Thank you!

builtnotbought wrote:Thank you very much for the answer!
Like this?

Yes.

builtnotbought wrote:Your theory about constant "+" at BRN wire will work if not mentioning one thing: that if I disconnect this plug as it was when I first start the engine (BRN/PNK to YEL/YEL) GEN lamp will be out while engine runs and battery NOT charging. So I think it's not BRN wire who's guilty.

Can somehow "+" signal сome to GEN lamp not using BRN wire at all but using these two YEL wires? For example Blower relay has constant "+" from junction on the firewall near the booster. Can "+" get to GEN lamp from junction if wires on blower relay are confused somehow?

When you say the alternator is not charging, what do you mean specifically?  You disconnected the main feed?  Or the plastic side plug with the RED and BRN wires?

If we assume the BRN/PNK wire is working as it should (12v only when ignition is on), there's only one crazy way I could see the GEN lamp getting 12v when the car is off: The ORN wire that feeds the blower relay (high speed) comes from the horn relay and has 12v all the time, even when the car is off.  If the wiring got screwed up somehow (or the internal circuitry of both the blower relay and the resistor pack) and power came from the ORN back to the YEL wire, then there would be a 12v supply back to the PNK wire when the car is off.  Since the ignition switch does not ground anything when it's off, the 12v doesn't go that way.  However, it's possible the BRN wire to the alternator is always grounded when the car is off.  Normally you don't notice anything because the lamp has no volts then.  But if now the YEL wires are supplying 12v from the ORN wire instead of taking it from BRN, the 12v could go from YEL to PNK directly and the lamp lights up when the car is off via the alternator plug BRN wire.  (Obviously this all assumes you have the BRN/PNK and double YEL wires connected.)

Try some tests:

1) When the car is off and the light is on, disconnect the plug on the side of the alternator.  Does the GEN light go out?  If yes, the 12v is grounding through the BRN wire in the plug.  If no, it has to be grounding through the ignition switch, which would make me think something is wrong there. Either way, we still need to find out why there's 12v when there shouldn't be.

2) Disconnect the ORN wire at the horn relay or the blower relay.  Does the light go out?  If yes, this is where the 12v is coming from, and somehow finding it's way back to the YEL wires -- either these two are connected somehow, or the blower relay and resistor pack are seriously screwed up.

3) Test the BRN/PNK connector to ground while it's disconnected from the double YEL.  There should only be 12v when the ignition is on.  Let's at least make sure this is working like it's supposed to.

4) Test the double YEL to ground when the car is off.  It should be dead.  If it has 12v, you have juice coming from somewhere it shouldn't.  My first suspect would be that ORN wire since that should be the only other source of 12v for the HVAC system.

What do you get?

Saying this i meant that voltage on the battery was showing 12v when engine running, not 14.4v as it should be when charging. I think BRN and Red wires are not in their places in plug because it looks like alternator sends "+" to lamp and ignition send "+" and alternator don't get impulse to start charging battery.
So there are 2 problems, lamp On when car off(2 YEL connected) and No battery charge and lamp out (2 YEL disconnected).


I will check everything that you told on Saturday.

Thank you

builtnotbought wrote:Saying this i meant that voltage on the battery was showing 12v when engine running, not 14.4v as it should be when charging. I think BRN and Red wires are not in their places in plug because it looks like alternator sends "+" to lamp and ignition send "+" and alternator don't get impulse to start charging battery.
So there are 2 problems, lamp On when car off(2 YEL connected) and No battery charge and lamp out (2 YEL disconnected).

Actually the alternator doesn't send + to the lamp.  It receives 12v from the lamp, which comes from the PNK wire.  The alternator keeps that circuit disconnected (so the lamp stays off) until it senses a problem, then it connects that wire to ground -- the 12v now flows through the whole circuit and the lamp lights up.

Most people think of a circuit that lights up a lamp like this:

BATT+ ------> switch ------> lamp ------> BATT -

But many circuits (including this one) work like this instead:

BATT+ ------> lamp ------> switch ------> BATT -

In this case alternator has the switch inside itself.  The result is the same either way -- the switch has to be thrown for the electricity to flow, but the switch can be on either the positive side or the ground side.

The other wire (RED) on the alternator also receives 12v (so neither of those puts out 12v), but it gets it from the rest of the system.  It measures this to determine how much to put out, or if there's a problem, throw the switch on the other one to light the lamp.  If the RED and BRN are reversed, it will definitely mess things up, but it should not light the lamp.  But that shouldn't happen unless you pulled the wires out of the plug -- the plug only goes in one way.

Thank you for explanation very much!

I pulled the wires out because i changed pins to new. May be i reversed them(

I have i think usual 3 wire alternator.
Is there any way to understand where is pin 1 BRN and where is pin 2 RED according to third stud location on the alternator body?

As I understand from what i can found pin 1 Red is closer to Battery + stud, isn't it?

Here you go, Demid.  Red is on the bottom and brown on top.

[quote="Mcarlo77"]Here you go, Demid.  Red is on the bottom and brown on top.

Cool! Thank you very much!

Noticed one more thing, that I relocated ground wire from alternator's bracket directly to engine block. I don't think it makes sense but may be need to check ground on alternator.

Mcarlo77 wrote:Here you go, Demid.  Red is on the bottom and brown on top.

Cool! Thank you very much!

Noticed one more thing, that I relocated ground wire from alternator's bracket directly to engine block. I don't think it makes sense but may be need to check ground on alternator.

Moving that ground to the block is fine as long as it makes good contact there. The alternator grounds through its own case and the brackets, so the same rule applies -- as long as one bolt has good metal-to-metal contact (no rust or paint) it will be fine.

So
1. Yes light go out if alt plug disconnected
2. + is getting there via ORG wire
3. BRN pink is hot only with IGN on
4. Yel are always hot.

Heater relay is ok, checked it.

Plug wires in relay the other way - Purple to blower motor is general, then after putting 12v switches to direct Bat high speed or resistor mid/low.

Everything ok, battery is charging 14.4v, all blower speeds are working BuT blower starts when ignition ON.

What is the right way of blower work?
Should it turn OFF with heater controls or it is always ON when car runs?
I pushed heater controls left/right - no action.

I'm looking at the scheme and don't understand in what way heater must be Off when ignition is On.
It feeds with + any way, through resistors on Low or through horn relay on High speed.




Thank you

Blower is designed to always run as long as the key is in the "ON" position.

With no joke?

Why did they do so?

I've read where Federal law was passed in the late 60's requiring all cars have the ability to draw outside air into the cabin at all times (Ign. "ON") to prevent possible carbon monoxide poisoning from exhaust fumes they thought were capable of getting inside. This coincided with the elimination of vent windows.

Mcarlo77 wrote:I've read where Federal law was passed in the late 60's requiring all cars have the ability to draw outside air into the cabin at all times (Ign. "ON") to prevent possible carbon monoxide poisoning from exhaust fumes they thought were capable of getting inside.  This coincided with the elimination of vent windows.  

Cool!

Today i cranked engine 3 times. Only last time alternator began to charge battery. I didn't touch anything between the cranks. All starts without choke on idle.

My friend tells me that this type of alternator begin to output energy only after revving engine up to 1200rpm, and if start engine on idle nothing will stir up alternator.
Is it truth? As i think it's not.

What can be reason of such tricks?

Thank you

The suggestion that a healthy alternator doesn't put out a charge at idle is ill-founded.  However, it's probably true that the amount of charge increases with RPM off idle...to a point.

Charging at idle is just one of the reasons that an alternator is so much better than a generator. A generator is the one that needs the RPM to begin to charge.
Older airplanes had that problem, and needed the idle up around 12 to 1500 RPM when using the radios. The conversions to alternators are getting common. I've done two of those in the past year.

I look at the GEN ( don't know why they still say GEN !)light as having battery + voltage on both sides when the alternator is charging, so no ground for the light. When IGN is on & engine not running, the lamp gets a ground through the diodes etc in the alternator, when it is not running/charging, and light is on...
Kind of a simple way to look at it I suppose...

Mcarlo77 wrote:The suggestion that a healthy alternator doesn't put out a charge at idle is ill-founded.  However, it's probably true that the amount of charge increases with RPM off idle...to a point.

I agree

pila wrote:Charging at idle is just one of the reasons that an alternator is so much better than a generator.  A generator is the one that needs the RPM to begin to charge.
Older airplanes had that problem, and needed the idle up around 12 to 1500 RPM when using the radios.  The conversions to alternators are getting common. I've done two of those in the past year.

I look at the GEN ( don't know why they still say GEN !)light as having battery + voltage on both sides when the alternator is charging, so no ground for the light.  When IGN is on & engine not running, the lamp gets a ground through the diodes etc in the alternator, when it is not running/charging, and light is on...
Kind of a simple way to look at it I suppose...

Lol, I thought that alternator and generator means the same gadget in English =)
So our cars have alternators not generators.

Yes I know that GEN light show how healthy alternator is, but the problem is that my light is on when IGN on engine not running, and light OFF when engine running, no matter charging exists or not.

When engine running and no charge exists, alternator is heating like crazy. Maybe smth wrong inside it...but I took it to Alt shop and they test it, but without disassembling.

builtnotbought wrote:My friend tells me that this type of alternator begin to output energy only after revving engine up to 1200rpm, and if start engine on idle nothing will stir up alternator.
Is it truth? As i think it's not.

What can be reason of such tricks?

Mcarlo77 wrote:The suggestion that a healthy alternator doesn't put out a charge at idle is ill-founded.  However, it's probably true that the amount of charge increases with RPM off idle...to a point.

This depends on the type of alternator.  The factory alternator produces voltage all the time, and varies its output based on pulley RPM (not the same as engine RPM) and what it senses is needed via the RED wire in the side plug.

1-wire type alternators (the kind I have) do not have the 2nd RED wire, so it has no ability to sense current need.  Therefore, the trigger to turn 'on' is when the alternator pulley reaches 1500 RPM.  Since the pulley is much smaller than the crank pulley, this happens sooner than 1500 engine RPM.  (I don't recall the exact ratio -- maybe 1000 engine RPM?)  Once the alternator is producing, though, it stays on until the car is shut off.

An important consideration for alternators is how many amps they produce at idle.  Obviously the lower the RPM, the less amps it will produce, but modern alternators produce much more at idle than older models from back when cars had much lower electrical demands.  This is why a modern alternator is a smart and popular upgrade these days, especially if you're going to have a lot of power accessories.

pila wrote:I look at the GEN light as having battery + voltage on both sides when the alternator is charging, so no ground for the light.  When IGN is on & engine not running, the lamp gets a ground through the diodes etc in the alternator, when it is not running/charging, and light is on...

The GEN light only has + voltage on one side ever (the PNK wire), and the alternator only produces + voltage from the large terminal on the back that feeds the rest of the system.  The alternator side terminal wires "take" + voltage rather than produce it.  The alternator simply decides in the event of a problem to switch the BRN wire from the light to a ground source (the alternator case) -- now the voltage flows through the light to ground in the alternator and the lamp lights up.

The issue Demid has is that the lamp has voltage on the PNK wire when the car is off when it shouldn't.  The ground on the BRN wire at the alternator is apparently normally connected to ground in its "off" state, which then gives the voltage (that shouldn't be there) a path to travel through the lamp to ground and light the lamp.

builtnotbought wrote:So
1. Yes light go out if alt plug disconnected
2. + is getting there via ORG wire
3. BRN pink is hot only with IGN on
4. Yel are always hot.

Heater relay is ok, checked it.

Plug wires in relay the other way - Purple to blower motor is general, then after putting 12v switches to direct Bat high speed or resistor mid/low.

Everything ok, battery is charging 14.4v, all blower speeds are working BuT blower starts when ignition ON.

What is the right way of blower work?
Should it turn OFF with heater controls or it is always ON when car runs?
I pushed heater controls left/right - no action.

I'm looking at the scheme and don't understand in what way heater must be Off when ignition is On.
It feeds with + any way, through resistors on Low or through horn relay on High speed.

1. This tells me the BRN alternator wire is normally grounded when the car is off.  This would not be a problem if the lamp did not have + coming from the YEL/YEL wires.

2. So the lamp goes out if you disconnect the ORN wire?  I'll dig back through the diagrams to see if I can figure out how + might be getting to YEL/YEL.

3. Good -- this tells me we're good here, and this is where the HVAC controls are supposed to get their power.

4. Ties with #2.  I presume when you disconnect the ORN wire these go dead when the car is off, right?

The non-responsive heater controls are part of this problem too.  Let me do a little digging and see what I can come up with.  If you can post a couple photos of these connections it will help me:

1. The wires to the heater controls
2. The wires to the blower relay
3. The wires to the resistor pack

I'm wondering if something got crossed or miswired, and I need to compare what you have to what the diagram says.

Thanks!

thatfnthing wrote:
This depends on the type of alternator.  The factory alternator produces voltage all the time, and varies its output based on pulley RPM (not the same as engine RPM) and what it senses is needed via the RED wire in the side plug.

1-wire type alternators (the kind I have) do not have the 2nd RED wire, so it has no ability to sense current need.  Therefore, the trigger to turn 'on' is when the alternator pulley reaches 1500 RPM.  Since the pulley is much smaller than the crank pulley, this happens sooner than 1500 engine RPM.  (I don't recall the exact ratio -- maybe 1000 engine RPM?)  Once the alternator is producing, though, it stays on until the car is shut off.

Does the 3-wires alternator need 1500RPM on pulley to start producing energy? Or as I understand it's controlled with red wire in plug.

thatfnthing wrote:
1. This tells me the BRN alternator wire is normally grounded when the car is off.  This would not be a problem if the lamp did not have + coming from the YEL/YEL wires.

2. So the lamp goes out if you disconnect the ORN wire?  I'll dig back through the diagrams to see if I can figure out how + might be getting to YEL/YEL.

3. Good -- this tells me we're good here, and this is where the HVAC controls are supposed to get their power.

4. Ties with #2.  I presume when you disconnect the ORN wire these go dead when the car is off, right?

The non-responsive heater controls are part of this problem too.  Let me do a little digging and see what I can come up with.  If you can post a couple photos of these connections it will help me:

1. The wires to the heater controls
2. The wires to the blower relay
3. The wires to the resistor pack

I'm wondering if something got crossed or miswired, and I need to compare what you have to what the diagram says.

Thanks!

Thank you for help! The mystery of GEN lamp always going on were these 3 heater relay wires not in there places:
Red was on the place of BLU and this took + through resistor to double YEL and then pink.

After I plug everything back in the right place, I got blower working always when IGN on, but Steve told that it's designed from factory.

Now the only problem I have with alternator is that it charges battery when he wants and GEN lamp is always off on running engine, no matter if it charges battery or not. I think it's something wrong inside the alternator because I started 3 times, 2 times no charge, last time charging ok. When no charge alternator is heating like crazy.

Alternator mystery reveal.

I connected voltmeter gauge to system. Switched off my electric choke so engine starts on idle rmp. This way volmeter always shows 12v - so alternator doesn't work and doesn't charge battery.

If now hit throttle and increase rpm a little, smth whistles a little I think it's an alternator belt, idle rpm changes a little according to sound and volmeter starts showing 14v.
Alt belt is stretched ok.

So increasing rpm's makes alternator switch on. I didn't have electric choke on previous engine and didn't have this trouble with this alternator...

Reveal №2.

It was alternator's belt. Low belt tension. Stretched belt with metal crowbar resting on alternator and tighten the bolt, everything in 4 hands. Before this I stretched belt myself with hands turning the alternator on the bracket.

But then new problem appeared. During air compressors are working voltage in the system goes down back to 12v from 14.
So I think I need more powerful alternator.

Now a days a 100 or 140 amp alternator is not hard to find. But maybe in russia you have like in Denmark guys that can fix broken alternators/starters ect. Maybe they can also rewire it to output more amps.