High Charging Rate. Found Voltage Drop Need Guidance Please

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This is an example of a Bosch spst high current NOTICE the difference: There is no normally closed contact. Both the 87 terminals are normally open

You can tell with an ohmeter by probing 30, and both 87 terminals. If there is NO continuity between 30 and either 87 terminal then it is an NO (normally open spst relay

relaydiag-spst.jpg
 
This is an example of a Bosch spst high current NOTICE the difference: There is no normally closed contact. Both the 87 terminals are normally open

You can tell with an ohmeter by probing 30, and both 87 terminals. If there is NO continuity between 30 and either 87 terminal then it is an NO (normally open spst relay

View attachment 1715377251
@67Dart273
Thanks for this. I checked the relay and the diagram on it and it is the same as your last diagram showing the SPST type. I also have the plug-in for it and each 87 terminal has a wire lead (12 gauge) on the plug so assuming power to each from 30. I will test that before I get the fix effort underway. With the voltage drop in the blue wire (trigger) has it at 11.6V will this be sufficient to trigger the relay in your opinion? Also do you see any issues with attaching 87 (1) to the ballast ignition terminal and 87 (2) to the voltage regulator terminal?
 
Yes the trigger should be fine

@67Dart273
@Mattax

O.K. guys I got my Pico connectors from Steve (4spdragtop). What a guy! I got back at my issue(s) this morning.

I was thinking that the bastardized wire terminal at the ballast ignition side would be the culprit but no such luck. Repaired I still had the usual voltage drop.

So I decided to go the relay route. All looked good as the blue ignition wire triggered the relay and I had battery voltage in the relay output wire to connect to the ballast. I setup a 3 way piggy back terminal for the ballast ignition side. 1. Batt. power from relay 2. Power wire to ECU from harness. 3. Wire to regulator from harness. I installed a new ballast resistor Mopar 209....
Ballast ground= .4 ohms.

I plugged everything in. Key on: the new ballast resistor started to smoke which I know is typical. I killed the power (key off) and thought I would check out resistance at the new ballast. Bare: Got zero ohms each side. Checked the old ballast. Same thing so might be my meter not measuring very low ohms. However I checked the top side coil wiring (disconnected) and got 21.6 ohms. I plugged in the coil side wiring to the ballast and got the same 21.6 ohms and 22.2 ohms on the ignition side (bare). I don't know what to make of this. Normal/Abnormal? Problem?

I didn't try to start the engine. It turns over as it should though with everything disconnected from the ballast. I need an opinion/guidance on whether I potentially have a new problem that has surfaced before I try a start up. Thanks!!
 
Sketch the wiring scheme you'e made.
Check it over and post it up.
There's different ways of executing 'wire around' whether its 'Crackedbacks' 'MAD' 'Nacho' etc.
With a schematic of what's actually on your car, it will be easier for both you and us.
Feel free to use any of the stock charging system diagrams I've posted as a starting point if that's easier.

Resistance - always checked with no power connected.
- Ballast resistor should be .5 to .7 ohms. Does that meter have different scales?

Stock Coil resistance, '73 Dodge FSM
About 1.5 ohms in the primary windings. Positive post to negative post.
From either post to ground should be open, infinte.
upload_2019-8-18_15-52-15.png
 
Sketch the wiring scheme you'e made.
Check it over and post it up.
There's different ways of executing 'wire around' whether its 'Crackedbacks' 'MAD' 'Nacho' etc.
With a schematic of what's actually on your car, it will be easier for both you and us.
Feel free to use any of the stock charging system diagrams I've posted as a starting point if that's easier.

Resistance - always checked with no power connected.
- Ballast resistor should be .5 to .7 ohms. Does that meter have different scales?

Stock Coil resistance, '73 Dodge FSM
About 1.5 ohms in the primary windings. Positive post to negative post.
From either post to ground should be open, infinte.
View attachment 1715380989

Thanks I'll do a drawing. FYI I installed "Crackedback's"wire around. Simply a 6GA wire from the alternator to the starter relay stud. Rob said that it reduces the load on the bulkhead and that the ammeter would show reduced current (discharge off center) which it does. Rob also said that I could optionally pull the wires off the ammeter and join them but not necessary if the wiring is in good shape (it is). Seems to work well and the car ran fine for years after the installation, except for what WAS the issue: Over Charging. With this setup the starter stud is receiving power from BOTH the alternator and the stock red wire from the battery? That was always confusing to me but as I said there were no apparent issues.

I thought I was away to the races with the relay setup. I really need an opinion as to why the run side terminal (two wires) fully disconnected at the ballast resistor would show an ohms reading of 21.6 (ignition side bare). Is that not a lot of resistance? Could be that has always been the problem since the blue ignition wire always had battery voltage that would drop to 11+ volts as soon as it was connected to the ballast. That's why I originally suspected the wire terminal as a cause. I'm totally baffled at this point.

To answer your question the lowest ohms setting on my meter is the 200. It does correctly measure ground point ohms at .5 .4 etc. But I got nothing (blank) when measuring both my previous and new ballast resistor.

Thanks much for your continued input and help.
 
I really need an opinion as to why the run side terminal (two wires) fully disconnected at the ballast resistor would show an ohms reading of 21.6 (ignition side bare).
I don't understand what is being measured. One probe into the run side connector and the other probe into what?
Maybe it will be easier with a diagram.
 
I don't understand what is being measured. One probe into the run side connector and the other probe into what?
Maybe it will be easier with a diagram.

Black probe to battery negative, red probe to run side terminal. I'm doing it the same way that I check ground points. Is this not right?
 
Black probe to battery negative, red probe to run side terminal. I'm doing it the same way that I check ground points. Is this not right?

This would show total resistance from "run side terminal" to ground post?
Is this what you wanted to measure?

If by "run side terminal" you are refering to the terminal on the ballast resistor, then we might be onto a hunt for a poor ground connection.
If it refers to the terminal with wires crimped to it inside the connector, then something is weird. Assuming the battery positive is not connected, it indicates a ground short.
 
This would show total resistance from "run side terminal" to ground post?
Is this what you wanted to measure?

If by "run side terminal" you are refering to the terminal on the ballast resistor, then we might be onto a hunt for a poor ground connection.
If it refers to the terminal with wires crimped to it inside the connector, then something is weird. Assuming the battery positive is not connected, it indicates a ground short.

Thanks. Yes I was referring to the wired terminal inside the connector on the run side not the ignition side. Sorry for the confusion. Reading was taken while disconnected from the ballast. However now that you mentioned it the positive battery terminal was hooked up at the time. Difference?
 
However now that you mentioned it the positive battery terminal was hooked up at the time. Difference?
If I'm understanding correctly:
With the battery hooked up, I have no idea what will happen. If the meter is set to measure resistance and is placed across voltage, somehting often goes up in smoke. One meter lead is on a ground, and the other on a wire that's switched off?? If it was on, then the meter may be damaged.
If the battery positive is disconnected, then the meter is indicating a fairly low reistance connection between the run circuit and ground. That's a short to ground!
 
If I'm understanding correctly:
With the battery hooked up, I have no idea what will happen. If the meter is set to measure resistance and is placed across voltage, somehting often goes up in smoke. One meter lead is on a ground, and the other on a wire that's switched off?? If it was on, then the meter may be damaged.
If the battery positive is disconnected, then the meter is indicating a fairly low reistance connection between the run circuit and ground. That's a short to ground!

I was assuming that there would not normally be power at that connection with key off and the ignition side of the ballast disconnected. Is that correct? I will try again tomorrow with the positive batt cable off.

Sorry to be such a challenge. I'm pretty good mechanically but electrical is pretty much zilch. I'm concerned about a short (fire), aren't we all. In your experience, all things being good, approx. how long would you expect a new ballast to emit smoke?
 
I was assuming that there would not normally be power at that connection with key off and the ignition side of the ballast disconnected. Is that correct? I will try again tomorrow with the positive batt cable off.

Correct.
So key off and that wire disconnected, would be safe.
Should be infinate resistance. Should be no connection to ground. Follow?
If not, make the sketch and we'll work from there.
 
Correct.
So key off and that wire disconnected, would be safe.
Should be infinate resistance. Should be no connection to ground. Follow?
If not, make the sketch and we'll work from there.

O.K. that was the condition when I got the 21.6 ohms measurement. Sorry I don't follow or understand what you mean by "infinite resistance" and no connection to ground. Does that mean in the above "safe" condition the ohms reading should actually be zero? I'll draw the sketch first thing tomorrow. Thanks for your input and patience. Have a good night!
 
O.K. that was the condition when I got the 21.6 ohms measurement. Sorry I don't follow or understand what you mean by "infinite resistance" and no connection to ground. Does that mean in the above "safe" condition the ohms reading should actually be zero? I'll draw the sketch first thing tomorrow. Thanks for your input and patience. Have a good night!
Here. we can prob work off of one of my generic 60s schematics for the concept.

upload_2019-8-18_20-42-36.png
 
The ignition wire is disconnected from the ballast resistor.
Key off should be equal to all the wires at the key switch being disconnected.
upload_2019-8-18_20-51-36.png

That does leave a possible connection to ground. The voltage regulator still has a ground connection (mechanical) and possibly through the rotor too in parallel.
Disconnect the power into the regualtor (blue wire) and a digital ohmeter should MegaOhms or the same symbol it shows when the probes are touching nothing.
 
The ignition wire is disconnected from the ballast resistor.
Key off should be equal to all the wires at the key switch being disconnected.
View attachment 1715381217
That does leave a possible connection to ground. The voltage regulator still has a ground connection (mechanical) and possibly through the rotor too in parallel.
Disconnect the power into the regualtor (blue wire) and a digital ohmeter should MegaOhms or the same symbol it shows when the probes are touching nothing.

@Mattax
Thanks much for the sketch. Sure saves me from an effort.

For clarity let’s start by labelling the various wires as identified in the ’65 Valiant FSM Wiring Diagram.

1. The 14ga brown wire shown at “Starter Ignition” is: J3

2. The 16ga dark blue wire at “Starter Ignition” is: J2

3. The IGN wire to the Regulator is: R5

4. The FLD wire from the Alternator is: R3

5. The run side of the Ballast Resistor: 2 wires joined: J2A J3

So the above establishes the “Stock” factory wiring.

The car is modified with Mopar Electronic Ignition ECU and Distributor. So an ECU power wire (Lt. Blue) was run to the ignition side connection of the ballast. Let’s label that wire: E1

Before any modifications J2 R5 E1 were joined together into a single crimped wire terminal plugged into the Ballast Ignition side. E1 was a soldered connection to the join.

Other than the voltage drop in J2 and by default also R5 the car ran well with no issues other than a resulting high battery charging rate. Thinking there was likely voltage drop in E1 also but apparently not enough to affect the ECU. ?

The co-joining of J2 R5 E1 at the ballast looked messy so the first modification I made was to separate them in the hopes that was the cause of the voltage drop. I connected each individually to a 3-way Piggyback plugged into the Ballast. No luck, still had the same voltage drop.

So I decided to modify further by installing a relay workaround as suggested by 67Dart273. J2 triggered the relay and out of “87” on the relay I have battery power. Let’s label that wire RL1.

So now my connection at the Ballast IGN 3-way Piggyback terminal is:

RL1 R5 E1 on a new Ballast Resistor

As per our more recent communications, Key On I saw smoke at the Ballast and bailed out. Didn’t try a startup but the car should start?? Unless another problem has surfaced. That’s when I started checking for other issues at the Ballast and got the Ohms reading at J2A J3 with everything disconnected at the ballast.

This morning I disconnected the battery positive and checked the J2A J3 join again and still got 22.6 Ohms. Wondering if that might be a cause of the voltage drop and the smoking ballast? Beyond me for sure.

Sorry for the long communique but at least there is now a clear view of the particular situation. Where to go from here?
 
I still have no idea why you are measuring that resistance.
This would show total resistance from "run side terminal" to ground post?
Is this what you wanted to measure?

As I saw when posting the diagram:
That does leave a possible connection to ground. The voltage regulator still has a ground connection (mechanical) and possibly through the rotor too in parallel.
Disconnect the power into the regualtor (blue wire) and a digital ohmeter should MegaOhms or the same symbol it shows when the probes are touching nothing.
In other words, I was wrong when I said this shows a ground short. There were still ground connections in the circuit, especially if its an electromechanical regulator.
I still don't know what you are trying to measure.

With the battery hooked up, I have no idea what will happen. If the meter is set to measure resistance and is placed across voltage, somehting often goes up in smoke. One meter lead is on a ground, and the other on a wire that's switched off?? If it was on, then the meter may be damaged.
If the meter has ever been connected to a voltage source while set for resistance, it may be damaged.

Lets go back to this.
Ballast ground= .4 ohms.
There should be 1/2 ohm across the resistor. In other words internally. If you lay it on a wood table and measure the resistance from terminal to terminal.
No grounding.
It's contained in an ceramic heat sink. If you lay it on a steel table there still should be no grounding. One probe on the table and the other to check each terminal and the result should be an open circuit.
No grounding.

When the resistor is wired to the coil, the coil has its own internal resistance. The primary coil windings are only gtounded through the points (or ECU). If there is continuity between the coil's terminals and the housing, it has short. Between he two terminals, the resistance should be as listed in the book.

So these are the resistance and continuity checks that can be made to check for ground shorts or excessive resistance in the ignition circuit.

Voltage drop is a check for excessive resistance when current is flowing through a circuit. In the case here, your observing (or looking to observe) a difference in voltage between the battery and the something downstream when the current is flowing out of the battery.
and
It is the difference between the alternator output voltage and some point downstream when current is flowing out of the alternator.
 
I still suggest you schetch/modify a diagram of your car's wiring.
It sounds like there are now 3 paths to the junction at the ballast connector (j2 R5 E1)

If there is still a drop, then need to figure out what they have in common, or disconnect each to isolate the problem.
Then you can hunt voltage drops within the circuit that's carrying the current.
While doing so you might just spot it visually.
That's not a bad thing.
wink-gif.gif
 
I still suggest you schetch/modify a diagram of your car's wiring.
It sounds like there are now 3 paths to the junction at the ballast connector (j2 R5 E1)

If there is still a drop, then need to figure out what they have in common, or disconnect each to isolate the problem.
Then you can hunt voltage drops within the circuit that's carrying the current.
While doing so you might just spot it visually.
That's not a bad thing. View attachment 1715381407

Your sketch pretty much nailed it. The only change was the addition of E1 (ECU) and RL1 replacing J2 at the ballast. J2 now just triggers the Relay. Anyway duty called (wife). I did bench check the ballast and it measured .8 Ohms. I'll get back to it tomorrow. Thanks much.
 
Your sketch pretty much nailed it. The only change was the addition of E1 (ECU) and RL1 replacing J2 at the ballast. J2 now just triggers the Relay. Anyway duty called (wife). I did bench check the ballast and it measured .8 Ohms. I'll get back to it tomorrow. Thanks much.

Just a quick note to close this thread off. Got the relay setup working. Car is running well. Battery is charging at a steady 14.4! Back on the road! Happy days!

Many thanks to @Mattax and @67Dart273 for your guidance, help and patience!!! You guys exemplify what FABO is all about.
 
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