Ignition Warning Lamp

VaCat33

VaCat33

Gold forum user
CAT Member
Messages
524
Hi All

This is a follow up to my thread about the charging problem I am battling. I took some more voltage measurements at key places in the system. Here are the measurements.

Battery……………………..………12.82v
V/R F terminal…………..……..12.82v
Pin 1 Ign Switch………..………12.82v
Pin 2 Ign Switch…………..……12.05v (Ignition in ON position)
Ign warning Lamp socket….12.05v (Ignition in ON Position) I also got a spark when the meter probe touched the side of the case
V/R D terminal……………………04v (Ign ON)
Generator BATT terminal…..0.4v (Ign ON)

The lamp lights but it appears the ignition warning lamp is shorting out and blocking the flow of current to the V/R and Gen. I have a new ignition switch on the way from SS.

Does anybody know where to source a new socket? I tried SS…they do not carry them. I also checked the British Wiring, they have a more modern version which should fit but I did not see anything that looked like the factory type socket. I am told there is also a guy up in Vermont with a stash of Brit Car stuff, but he is not answering his phone. Any other U.S. based sources would be appreciated. I have attached a photo of the socket. It is a bit washed out but you can see the white wire into the back of the socket and the brown yellow wire attached to the socket case.

I am under the gun since my car is in the Pinehurst Concours on 2 May.

Thanks.
 
SAY HUH !

VaCat33 said:
Hi All

This is a follow up to my thread about the charging problem I am battling. I took some more voltage measurements at key places in the system. Here are the measurements.

Battery……………………..………12.82v
V/R F terminal…………..……..12.82v
Pin 1 Ign Switch………..………12.82v
Pin 2 Ign Switch…………..……12.05v (Ignition in ON position)
Ign warning Lamp socket….12.05v (Ignition in ON Position) I also got a spark when the meter probe touched the side of the case
V/R D terminal……………………04v (Ign ON)
Generator BATT terminal…..0.4v (Ign ON)

The lamp lights but it appears the ignition warning lamp is shorting out and blocking the flow of current to the V/R and Gen. I have a new ignition switch on the way from SS.

Does anybody know where to source a new socket? I tried SS…they do not carry them. I also checked the British Wiring, they have a more modern version which should fit but I did not see anything that looked like the factory type socket. I am told there is also a guy up in Vermont with a stash of Brit Car stuff, but he is not answering his phone. Any other U.S. based sources would be appreciated. I have attached a photo of the socket. It is a bit washed out but you can see the white wire into the back of the socket and the brown yellow wire attached to the socket case.

I am under the gun since my car is in the Pinehurst Concours on 2 May.

Thanks.
Click to expand...

I'm not convinced that the socket is shorting unless it's been damaged. More likely it's returning current thru the bulb. Remove the bulb and test both leads again before spending money. Trace the leads to their source. 2-cents
 
I took out the bulb and retested, as Oneoffive suggested. Reading was 12.2v at the bulb base...but still 0.1v at the D terminal on the V/R (same as with the bulb in.) Something is preventing the current from getting from the bulb base to the V/R. I am hoping a new bulb holder will recitify that.
 
The good news ...I obtained a replacement BA7 bulb holder for the ignition warning lamp thanks to 65SUNBEAM who overnighted it to me. I just installed it.

The bad news...nothing changed. With the Key ON, the voltage still reads only .02 @ the D terminal of the V/R. I checked the voltage at the Ignition warning lamp socket and it was 12.2. With the car running the lamp stays lit.

Something is impeding the flow of current running through the brown/yellow wire between the warning lamp and the D terminal of the V/R. Unfortunately, this wire enters the harness a short way from the warning lamp and exits right at the V/R. Other than recheck the connection at the V/R D terminal, not sure what else I can/should do.

All ideas welcome.
 
Wire short?

Just a note that after pulling the harness out entirely, a cursory view by the expert deemed the cabling to be "OK."

I went through few areas one by one, and missed some heat shrunk coating that was overlooked. Once the tape was removed, there were a number of shorts / burned cabling along the wire cable itself. (my case: the seemingly common ignition / white)

The good news is that you seem to have narrowed down to a particular circuit / wire? the bad news is that you may need to look closer and UNDER the tape along the harness. Not easy in situ. Or perhaps the connector / solder joint itself at either termination?
 
Before You Rip Up Your Harness

VaCat33 said:
The good news ...I obtained a replacement BA7 bulb holder for the ignition warning lamp thanks to 65SUNBEAM who overnighted it to me. I just installed it.

The bad news...nothing changed. With the Key ON, the voltage still reads only .02 @ the D terminal of the V/R. I checked the voltage at the Ignition warning lamp socket and it was 12.2. With the car running the lamp stays lit.

Something is impeding the flow of current running through the brown/yellow wire between the warning lamp and the D terminal of the V/R. Unfortunately, this wire enters the harness a short way from the warning lamp and exits right at the V/R. Other than recheck the connection at the V/R D terminal, not sure what else I can/should do.

All ideas welcome.
Click to expand...

It sounds like you believe there is a problem with the wire, which could very well be. Before you tear into the wiring loom, can you disconnect at both ends the wire you believe to be the culprit and check its resistance? Or while it is disconnected, temporarily run a new piece of wire in its place, connecting at both ends and then seeing if you get light? You may have already done these, but thought I'd throw out some ideas. Of course, if the existing wire shows high resistance or if a temp wire leads to a working light, you know where the problem lies and you will still need to track it down. Just first make sure you have isolated where the problem is.
 
lamp

the warning light should have no effect on anything. it has one wire that plugs onto the same terminal on the voltage regulator as the wire coming from the generator. this wire runs to one side of the warning light. the other wire from the socket runs to terminal 2 of the ignition switch. you could unplug both wires and the only thing that would happen is the warning light would be unhooked. these have no effect on the voltage to the rest of the car. is the warning light like a test lamp that is testing whether there is voltage coming from the generator?
 
I am learning on the fly...the comments of 65beam and others woke me up to the fact that I had all this backwards:(. I followed the brown/yellow wire from the lamp and thought current flowed from the warning lamp to the arm (D) terminal on the V/R. From what has been said, now I see that it actually flows back from the generator to the D terminal and then to the lamp via the brown/yellow wire which serves as a test if the generator is generating.

Although the generator and voltage regulator are good (they bench-tested perfectly), the generator is not generating in the car. So I am back to some basics...starting with making sure the generator has a good ground. Standby for more of the Adventures of VaCat33 in the Land of the Electronic Wizard.:)
 
I tested the generator with the car running and the generator grounded with an extra ground. I used a ground wire (10 gauge brown wire w/30 amp clamps) clamped to the back of the case and an exhaust manifold bolt. See photo. I also tried it clamped to the G terminal on the generator. Still only generating about .25v at the Batt terminal @ 1300rpm. Warning light stayed on. I was hoping that with the battery now at about 80% I might see some voltage at the generator Batt terminal if it was generating...no luck.
 
red light

That 'harmless' ignition light is not so harmless. For the record, everything in my electrical system works perfectly, including all instruments, lights, every switch, wipers, blowers, charging system- everything- except the clock, but, that's internal to the clock. One day I was under the dash and found this disconnected wire. Figured out it went to the ignition warning light. Thought to myself, "No wonder the ignition light never comes on." Connected the light, turned on the key. Voila! Ignition light came on. Started the car...ignition light still on...what's this? SMOKE! Turned off car, disconnected ignition light, thought to myself, "No wonder the wire was not connected!" Haven't been back to revisit the situation.

What do you think is the issue with my red light?

Kirk
 
65beam et al

I have a wiring diagram but unfortunately my analysis of it sent me off in the wrong direction. I consequently focused on the warning lamp...incorrectly. It was a waste of time, effort and money but I did learn from it.

That said, I still have not found why a generator and voltage regulator that bench-test perfectly, do not charge the battery once installed in the car. :confused: I have cleaned my ground straps and connections and even tested the generator with it grounded directly to the negative post on the battery.

Again, any ideas are welcome.
 
Have you double checked the wiring connections between the components?
A high resistance wire or connection point will upset the voltage supplied.
 
I have checked and cleaned the connections. I have not inspected the wiring itself, since most of it is encased in the harness.
 
Wire Gremlin

VaCat33 said:
I have checked and cleaned the connections. I have not inspected the wiring itself, since most of it is encased in the harness.
Click to expand...

Don't over thunk it: If, in fact, the components both bench tested good (trusting the bench), then I would immediately suspect that something is preventing current flow between them. Do both units have proper grounding? I'm fond of long & hefty jumper wires by-passing all the clutter. If things function once jumped, then introduce the clutter piecemeal until the culprit is found. If things DO NOT function once jumped, the bench fibbed.
 
lamp

do you have an amp guage and if so have you checked the connections to it?
 
65beam & Oneoffive

Yes, I have an amp gauge. It was one of the first things I looked at. I disconnected it, cleaned all the contacts (I use ring terminals secured by nuts and lock washers) and I then re-secured the contacts.

I thought about the bench test fibbing (I watched them do it and saw the readings myself)

so, I used a ground jumper between the negative post on the battery and the G terminal on the generator. With the car running still no charge. I must admit I did not do a similar ground jump at the V/R. That will be next.
 
Check this...

So, it sounds like you still have a charging problem, and the Gen light on?

It sounds like an Amp Meter problem.

Depending on how the Amp Meter is wired, the meter it's self may be bad.

I have seen an Amp Meter that by all indicators seemed good but in fact was
bad.

Consider shorting the amp meter main terminals together and checking the charging system.

DW
 
DW

You could be right on target. I have eliminated just about everything else except for eliminating the ammeter from the equation. I do not think it is the connections on the ammeter. I use ring terminals secured by nuts and lock washers and I cleaned all of them up early on in this process, just to be sure. The ammeter itself is becoming a strong suspect and definitely worth a look.

Thanks
 
You must log in or register to reply here.
Back
Top