Charging System Troubleshooting--Blown Ignition Light Fuse?

[patrickt]

Originally Posted by ACHiPo

An update from yesterday. The problem is not fixed. When I turned the ignition "ON" yesterday, no ignition light. Checked fuse 3 and sure enough it was blown. Replaced the fuse with a 15A one and it blew as well. Changed the wiring back to Bob's recommended configuration eliminating the stator connection on the alternator, removing the "I" spade from the VR, and jumpering the A and S spades on the VR. The pink wire is still disconnected from the fuel sender. The charging works again, but of course no tach or anything else on the ignition circuit.

And with all that disconnected, if you put a fuse in #3 it still blows?

[hauss]

If you would like, I would let you borrow my tester, it is a very high quality unit I paid over 900$ for. You may use it as long as you would like. Met you at the restaurant a year or so ago and you took me for a ride in your superformance. There are instructions in the case and you will need AA and 9v batteries Hope this helps you.

[patrickt]

Originally Posted by hauss

If you would like, I would let you borrow my tester, it is a very high quality unit I paid over 900$ for. You may use it as long as you would like. Met you at the restaurant a year or so ago and you took me for a ride in your superformance. There are instructions in the case and you will need AA and 9v batteries Hope this helps you.

I vote "Yes."

[ACHiPo]

Originally Posted by patrickt

And with all that disconnected, if you put a fuse in #3 it still blows?

Haven’t tested that yet.

[ACHiPo]

Originally Posted by hauss

If you would like, I would let you borrow my tester, it is a very high quality unit I paid over 900$ for. You may use it as long as you would like. Met you at the restaurant a year or so ago and you took me for a ride in your superformance. There are instructions in the case and you will need AA and 9v batteries Hope this helps you.

John,
I’m interested in the tester if it will help find a short. Are you coming to Cobra Day?

Evan

[hauss]

Sent you a p.m. Yes the tester is a high quality tester just read all the instructions Play with it all you want keep it as long as you need.

[ACHiPo]

John,
Thanks again. Responded to your PM. I'm curious what kind of tester it is and how it works.

Evan

[hauss]

NO thanks needed, you are a good man. I emailed you some pictures . I have not forgotten my promise about breakfast so I will make it up to you and bring you the tester.

[ACHiPo]

That Ideal tester looks very cool. Not sure it's small enough to troubleshoot my car wiring loom, though?

[patrickt]

Originally Posted by ACHiPo

That Ideal tester looks very cool. Not sure it's small enough to troubleshoot my car wiring loom, though?

Fortunately, Fuse #3 does not carry much amperage at all. I know you don't want to but, starting at the far end of the circuit, and then snipping the wire, in stages, until you can run what's left of the circuit without the fuse blowing, and then slowly butt-crimping the wire back until the short re-appears, works every single time, especially with funky intermittent faults that seem to come and go. With wipers running, the heater fan on, and all gauges working, I bet that circuit doesn't pull but five amps. For something like that, a butt-crimped line will work just as well as a brand new wire, and no one will know the difference. (It's what I would do, and then heat-shrink the butt-crimps and they'll look OEM, not that anyone will every be looking at them.)

[hauss]

Dropped off the tester today .Hope it is useful . IT has many functions and comes with a amp meter It is a Ideal suretrace open/closed circuit tracer #61-957

[strictlypersonl]

Originally Posted by ACHiPo

That Ideal tester looks very cool. Not sure it's small enough to troubleshoot my car wiring loom, though?

Evan,

I'm hoping the cause is in between the voltage regulator and the ignition warning light. What I will do is give you a replacement for everything in that circuit, from regulator to light to power. The leads will be long enough to test before a permanent install parallel to the original leads.

Bob P.

[ACHiPo]

Thanks Bob and John! Need to focus on getting the car ready for Cobra Day, but hope to get back to troubleshooting Sunday.

[ACHiPo]

I'm finally getting back to troubleshooting.

I ordered one of these:
https://www.realfixesrealfast.com/short-finder.html

Basically an automatically resetting 10A circuit breaker with a Gauss meter to detect current.

I clipped the CB to a test light to have a visual indication of the breaker tripping and replaced fuse three with the set up.

I reconnected the stator and VR to the circuit, but left the pink wire from the dash to the fuel sender disconnected.

When I turned the key to ACC, the test light lit, but the ignition light did not. Also, the CB did not trip, suggesting it's either way more than 10A (15A fuses blow in fuse 3), or faulty. I turned the key to "on", and again no ignition light and no CB trip. I started the car. The ammeter was charging, but no tach. The test light remained lit, although it seemed a bit dimmer than when the key was in the on or acc position.

I reconnected the pink wire to the fuel sender and no change--no acc or on ignition light, car started fine, and ammeter worked. I disconnected the pink wire again.

I inserted a 10 Ohm shunt resistor in parallel with the ignition bulb Bob sent me. The purpose, according to Bob, is to add current to the VR energizer circuit guaranteeing actuation.

I removed the CB from fuse 3 and repeated Patrick's test with the auto-reset CB + test light jumper between the ACC terminal and the outer (double green wire) tab on the ignition light. Both the ignition light and test light lit (although dimly).

I put everything back together, put a fuse in #3, turned the key to acc, and the ignition light illuminated. Turning the key to "on" and the ignition light still lit. Starting the engine, the tach worked, the gas gauge moved off E, the ignition light was not on. Everything seemed to be working correctly.

I reconnected the pink wire to the fuel sender and the 15A fuse 3 blew. I disconnected the pink wire, replaced the fuse with the CB and test light. No ignition light, no tach. Started the engine, the CB did not trip, the tach didn't move, the ammeter showed discharging, but not charging.

I'm now thinking I have two issues: 1) a ground loop or short in the pink wire to the fuel sender, and 2) an intermittent VR.

Thoughts?

[DanEC]

Thoughts - man, you have a lot of patience and perseverance Evan. I'm no help but hope you get it figured out before long.

[ACHiPo]

Dan,
Thanks. I've basically taken a 3 month hiatus. Just now getting back to it. The fact that it almost kinda works makes me think I'm definitely gaining on it. As the joke about the optimistic kid goes, "there's got to be a REALLY COOL PONY under a pile of poo this big!!!"

[Gaz64]

Originally Posted by ACHiPo

I'm finally getting back to troubleshooting.

I clipped the CB to a test light to have a visual indication of the breaker tripping and replaced fuse three with the set up.

When I turned the key to ACC, the test light lit, but the ignition light did not. Also, the CB did not trip, suggesting it's either way more than 10A (15A fuses blow in fuse 3), or faulty.

Thoughts?

A 10A CB will never trip with a test light in series, unless the lamp is 120w.

Gary

[ACHiPo]

Originally Posted by Gaz64

A 10A CB will never trip with a test light in series, unless the lamp is 120w.

Gary

Gary,
Why do you say that? I could understand if the lamp was in parallel with the breaker, but in series amps is amps. What am I missing?

Evan

[fintubi]

I didn't have any of your other symptoms, but I recently discovered that the white and pink wires were reversed at the fuel sender in #3014. Since my car has SW gauges and no requirement for the pink hot wire, this means:

1. fuel gauge was inop because the white sender wire was no-connect at the sender; and

2. the 30-240 ohm fuel-level rheostat in the tank was functioning as a 0.6-5 watt heater because it had +12V applied to it via the pink wire.

Bill

[patrickt]

Originally Posted by ACHiPo

Gary,
Why do you say that? I could understand if the lamp was in parallel with the breaker, but in series amps is amps. What am I missing?

Evan

Let's not get side tracked on that. Gary is taking 12v and multiplying by 10a and saying that you have to have 120 watts to blow the circuit breaker. Instead, I think you should try this approach: 1) Tape off the pink wire that goes to the fuel sender. We're not going to 'untape' it, for any reason, until we have all other charging system issues fixed. 2) Put a fresh, known to be good, fuse in slot #3 and put the CB tester and test light on the floor. 3) Turn the key first to the ON position, but do not start the car, and observe the charging light on the dash (should be on). If it is not on, stop the testing and report back. If it is on, start the car and see if the light goes out and the ammeter gauge is working properly. Report back.