1968 (build date December) Convertible with Factory Air-(not working)

When the engine is running the Gen Light is on and will not go out till the engine is off. The Alternator is putting out 13.6v +/- pending on the load. I believe the regulator is the problem as the Alternator is a new rebuild. The Regulator has a burnt look to the coil where the brown wire is connected to pin-4.

What I am having a problem with is when I push the relay on the regulator (pin-4) where the Brown/Gen Light wire is, I hear a relay making and breaking. The Gen Light goes off and on as I push this contact, I traced this to a relay on the inside of the driver side kick panel. The relay has a orange & red/white wire. I still have to disassemble the kick panel and remove the parking brake to inspect and follow these wires.

Any ideas to what this relay is? All the wiring diagrams are clueless to this relay and wire color code. It might be part of the A/C system as the car had factory A/C.

Ideas anyone?

I currently have a similar problem with my regulator.

The gen light has come on with the engine off and key removed. After a rap on the regulator with the handle of a screwdriver, the light went off. Now and again the gen light comes on when the engine is running, but turns off when the engine is shut off. If I rap on the regulator when the engine is running, the light goes off. All of this happens about every three or four days, but does not act up in-between.

I purchased the regulator in March from Ames. I am going to give them a call and see if they will exchange or do anything. I am convinced the entire charging system is fine, just a bad regluator.

But perhaps you have a different issue with yours. All the connections on my regulator look fine, and I did not hear any relay clicks, but I admit I was not listening for something like that.

Sounds like a defective regulator...cheap enough to replace before you start chasing down wiring problems.

The Gen Light goes out when the power is turned off. I was trouble shooting the regulator and was able to switch the gen light on & off by pushing the relay that is connected to the brown wire to the dash gen light. At that time I also heard a relay clicking, the dash light goes on and off per the regulator and so does the relay.
I feel the regulator is at fault but I am lost as to what the relay is. I found a replacement regulator at napa and will try that option out. All the A/C diagrams show a master relay but the wire colors are wrong and the number of wires used and the location is in the wrong area.

Keep the replys coming.

Bob

If you put in a new regulator, let us know if that solved the problem.

I am looking for a Cap that plugs into the regulator also. The Cap is pluged into the same pin as the brown wire to the Gen light. I am going to unplug it and see if that changes the game plan.

Ames has them backorderd and Classic has discontinued them. Only one MFG is making them at this time except NOS.

Wonderful!!

I guess I'll be carrying that screwdriver around with me for the next month or so...

Found a replacement Cap From:

Lectric Limited, Inc.
6750 W. 74th Street - Suite A
Bedford Park, IL 60638
U.S.A.
1-866-624-1850 Toll-Free
http://www.lectriclimited.com

01960957 RADIO CAPACITOR: VOLTAGE REGULATOR, -reproduction-, (mounts to voltage regulator, connects to ground tab on regulator)

It cost more than I want to pay but it is the real deal. This web site has lots of hard to find items for our older cars. It should be here in a few days oh well.......

I was wondering what you meant by "cap". Now we know! That capacitor is just to keep RF noise coming through the radio. Won't make a difference in alt or reg performance.

Well I used a new voltage regulator and the gen light is still on. There was no electrical voltage difference between the new and old other than burnishing of the coils and no way to adjust the voltage. I have been looking at many different wiring diagrams and found a Pontiac diagram (nonspecific) that shows the brown wire going to the ignition switch then pairs off two wires to the Gen light and elsewhere, I will look at it more closely to where it goes.

Back in the 70's I had auto shop at the JC and still had some notes & Echlin tech bulletins from 1972 this is for the Delcotron System.

1. This is what is called the resistor test:

If the system is equipped with a signal lamp remove the connector block from the regulator. Connect a Voltmeter from pin-4 terminal on the connector plug to ground. Turn the ignition switch to the ACC position. The voltage reading should be approximately 12 volts. If there is no voltage reading, the resistor or resistor wire connected to the ACC terminal of the ignition switch is open and must be replaced.

In doing the resistor test my results show the voltage at 10.5volts which is within spec.

2.Signal lamp test :(TO BE DONE TONIGHT)
Connect a jumper wire from pin-4 terminal on the connector plug to the F terminal (first pin). Turn on the ignition switch. If the lamp does not light the bulb may be burned out (it works), or the alternator brushes may be worn (have new Alternator) or sticking in the holders.

There are two more test to do after this:

3. Field Relay Test.
4. Alternator Test.

I will list these as I do them. I need to make 5 jumper wires to do these tests. The test requires some wires hooked up and other split.

Does anyone have a drawing showing the brown wire going to the igition switch?

Check this out:

http://thefirstgensite.com/html/68wirindex.html

Hi Jeff and Thanks for the link

Yes, the brown & brown/white wire does goes to the ignition switch. I am going to take a closer look at the wiring and connector on that switch. I might need to replace the switch, as the gen light is on all the time. The instrument cluster is out and I have easy access to the switch. The ignition switch from that terminal powers the Radio, A/C, Heater Switch & Wiper/Washer.

Now that I think about it more, I replaced that switch when I bought the car, so I had the only keys. I got the switch from Classic Industries awhile ago. I will dig thru my spares box for the old one and try that.

Another thread (wire) to chase.......

I had a similar problem, turned out to be a bad ground. Make sure the instrument cluster ground strap is in place when you put things back together. Electricity isn't magic, but it certainly does funny things when allowed to roam free!

Thanks Jeff

That was one of my first projects was to replace the clear plastic bezel on the instrument housing. I made a good ground strap and used crimp lugs to connect it from the back of the housing to ground. I glass beaded the housing as it was rusted and repainted to stock colors including the bare metal on the back which made it look good and have a finished look. I took special care not to paint areas that need to be bare metal. I just wish the Speedo cable was easier to R&R, my hands are large and it is a tight fit to get to it not to mention dropping the steering wheel column.

Disconnect the cable from the trans side and then you can give yourself some slack by pulling/pushing through the firewall...[censored] near impossible without doing that.

Thanks Jeff

Glad to know that there are veterans that have been there done that for us climbing the ladder of knowledge.

Just a Flesh Wound

No problem.

Well I did the signal lamp test last night and it was in Spec. the lamp turned on.

3. Field Relay Test

If the signal lamp is lighted with the connector in place and the engine running at a fast idle, the field relay which is located in the regulator may be faulty or there may be trouble in the alternator.

Connect the VOM to pin-2 to ground. With the engine running at a fast idle, if the VOM reading is 5volts or more the signal lamp remains lighted, the field relay is faulty and the regulator must be replaced.

This test was a fail but when I replaced the regulator with a new one it failed also. This blew my mind and I started to look elsewhere for the problem. I found a fuse blown in the fuse panel but is was for the backup light? The fuse on the bottom left of the fuse panel 10amp?

Now the lamp is on and off intermittently go figure. It is now normal I can’t seem to tie this problem to a single fail point

Replaced:

1.Alternator (was bad failed bench test someone sprayed silver paint all over it)

2.Voltage Regulator (Still not sure new one is the right one)

3.Alternator 2-pin connector (very worn and questionable pin fatigue)

4.10amp fuse (not related)

5.Voltage Regulator connector (very worn, not done yet ,on order)

6.Ignition switch (suspect intermittent, not done yet, on order)

Back to the drawing Board.............

Did you by chance replace the circuit board on the back of the cluster. I had an "always on dim" condition with the right signal lamp that turned out to be a bad connection at the circuit board, I'll guess, due to the fact when I replaced the circuit board the lamp now functions properly.

Hi Jeff

I am still using the original circuit board. I have it at work today to repair a trace to the connector slot. When I was in trouble shooting mode I was constantly plugging and unplugging the darn thing and one trace needs to be re-glued back down. I haven’t looked up what trace it is yet. When I restored the cluster I did a check on all the traces and they checked out. The new damage could be the culprit. I am leaning on the ignition switch as it seems to be a little sloppy. I did change the key tumbler out, not the switch itself when I picked up the car.

I looked up the trace and I am repairing the common for Temp, Gen, Temp, & Oil. The trace lifted up at the very end where it drops down into the socket. I will clean all contacts till they are shinny new looking again.

I hope this is the end game I will find out tonight.

Those old boards due tend to due some strange things intermittently. They curl and lift when it gets hot and shrink when it gets cold.

Hope you get it figured out!

Well in trying to repair the copper leads to the plastic, I fix one and another separates. I think that the circuit board is the problem. I hate to spend the bucks but I got to replace it, because it is in such a hard place to get to. I want to get it done and know it is good.

It looks like I will get to it when I get back from vacation, my kitchen pass expires Friday and I fly up to Washington to spend a week and drive the wife home.

Bob…

Well in a last minute test my friend loaned me his 67 speed cluster to test the bad circuit board theory. I still am now having the same problem with the Gen light coming on and off randomly. The next item will be the ignition switch test. I have one coming from Classic and will give it a go when I get back from Washington.

Bob....

Well back from my short vacation and back to ferreting out this problem. I have a new circuit board and ignition switch to test with. My good friend needed his speed cluster back so he could drive his ride.

I saw an earlier post from Vikky (Yellowbird) which had a link to the Pontiac charging system (Great Info!) and will look for the splice and give it a good visual for corrosion.

Bob...

Bob, This is an excellent thread. I am having a similar problem with my gen light on dim and intermittent. I have a small garage and have to test when I can pull the car out and have time to work on it. Please keep your findings coming. They are extremely helpful to me.

I work with an electrical engineer and have feed him information on my symptoms. He is currently going through the wiring diagrams and information provided by Vikki and this post. I'll let you folks know what he comes up with unless I find it on my own. Unfortunately work keeps getting in the way of both of us troubleshooting my problem!

Thanks again to Vikki, Jeff, and yourself.

For whatever help it may be worth:

Well I lost my kitchen pass tonight, I forgot we are going to Crosby, Stills & Nash concert at the Santa Barbara Bowl, so it will be Wednesday before I get to continue on the GEN light quest.

Bob....

Rats, The Concert was canceled and rescheduled for 1 October and the wife has me for a date night. Wednesday it is for troubleshooting the light.

Thank you Jim for the flow chart. I will run the flow chart test and see what happens.

Helitech PM me when you get a chance.

Bob....

I changed the ignition switch last night and the outcome has changed again.

The Gen light has changed from full on, to dimly Glowing.

I put back the old ignition switch and the Gen light just glows as with the new switch.

I plan to do voltage test today on the regulator again to get a baseline. Jim has shown me a good Flow Chart to do testing

The regulator is working as the alternator is putting out 14.32 volts and the battery is at 14.13 volts at idle.

The regulator is a NAPA replacement and it may be the problem child. The 67 Pontiac charging circuit file shows a flow chart that Jim posted on checking the GEN Light, I plan to do this again to recheck all items.

I replaced:

Alternator
Regulator
Regulator Cap
Alternator plug (2 wires)
Ignition switch
Circuit membrane on back of Speedo Cluster.


Back to square one! At least I have parts to test with.

Bob...

I had some funky stuff happening with bad grounds in the headlamp harness (either side of rad core support) check those out real good. Is there a change in the brightness of the GEN lamp when you turn on the lamps? Just more stuff to check! But it did cause an anomoly in the GEN lamp circuit amongst others.

I forgot that I still have that relay in the drivers side, behind the kick panel that energizes when the regulator coil makes.

My guess it is part of the A/C.

Pins 3 & 4 of the regulator, pin 4 goes to the ignition switch/gen light. Then splits off I think to the fuse block to power three fuses.

This adds to the fun....

Anyone have an idea what that relay does? or even seen it?

Bob....

Hi Jeff

I did not think to turn on the lights when I was testing the new switch. I will give that a try tonight and post the results.

You have a very valid point on the grounds I always overlook checking those out.

I plan to unwrap the tape and take a look of the red wire splice and give it my eyeball for corrosion.

Bob....

I looked at the A/C relay diagram and it gets power from a wire with a fusible link inline straight from the alternator, or at least that's what it looks like. If you pulled the relay it would be interesting to see what happens.

Good luck and let us know!

Hi Jeff

When I pull the parking brake assembly I can remove the kick panel. I did put my hand on it and it has 2 wires, orange & red/white wire going to a simple relay. No clue to the colors and where they appear. My car did have A/C, I plan to pull the parts out and install an A/C Delete Panel.

Your right I can pull the connector off and see what happens.

On my bucket list.

Results to follow.......

Bob

Well I did the Generator Indicator Lamp Test per 1967 Pontiac Engine Electrical tonight. The flow chart states that I need to replace the regulator, the lamp test failed.

That said the Gen light is just barely glowing is that a on or a maybe?

I have a new regulator coming in the mail this week from Classic Industries, for the price I paid it might be gold plated.

The only other thing that I might do is replace the plastic connector to the regulator. It seem worn and well used.

I guess I will test again when I get the new regulator. I hope that I can return the Napa Parts regulator for a credit.


Bob...

Hi Jeff

I turned on the lights tonight and there was no change in brightness on the Gen Light. The Alternator is putting out 14.83 volts at idle with the lights on and 14.34 at the battery.

That said I forgot to read the voltages off the regulator to see if it is 5 volts or not.

Flow chart states if it is above when running the regulator is bad. I will test this in the next day or so, (need to renew kitchen pass).

Bob.......

Wow! heck of thread. I need you to stop by and figure out why my Generator gauge on my Ralley setup doesn't work once you get this figured out.

I had a 85 Caprice where the gen light would lightly glow. I replaced the alternator twice then just lived with it for a couple years. Ended up being a bad diod in the alternator. Must have been a bad batch of them.

I would sure like to see a simplified drawing of how the gen light works. It would make the trouble shooting alot simpler.

Well I got my parts in the mail from Classic Industries today. I got a whole weekend to chase sparks & arcs, and try to resolve this problem.

The Regulator is a Delco part and I hope that this is the end game (sounding like a broken record).

When poking around I noticed that there is a solenoid on the driver’s side firewall which is down low near the starter. This is an afterthought from some previous owner kluge? It looks like that I am going to rewire my whole starting and charging circuit before I get to move on to other fun challenges.

Also I found that there is an extra red wire from the horn relay to the firewall, I plan to find out where that goes. Maybe the drop-top motor, A/C or power windows? Looks like a factory install.

I just finished a complete 4 wheel disk brake with e-brake install (complete with shedding the last of my gray hair). Had the TH-400 rebuilt. Rebuilt the rear end. Now the electrical. Fun Fun and more Fun.

Results to follow………… (pending a free Weekend Kitchen Pass).

Bob….