!969 Charger Gages Slow to Start Working - Help

Chasing some electrical gremlins. My gauges work almost instantly when I turn the key to accessory but take about 5-10 minutes to start working after I start the car. I replaced the original dash voltage regulator with a new solid state piece and I have the same problem. On a possible related gremlin, car will not fire when cranking but starts the moment I release the key. I quickly checked and I don't have voltage to the start pin in the bulkhead. Any ideas? Possible ignition switch?

Usually when it only starts after you release the key it's a ballast resistor issue, but if you have no voltage at the bulkhead pin it's most likely the ignition switch.

Check at the output of the ignition switch to verify.

If you have voltage there but still not at the BH, could be a flaky bulkhead connection. On the gauges, could be related or a separate issue. resolve the start issue first.
Once that is resolved if the gauges are still acting up, do not forget to check and verify your grounds between the battery, engine, body and dash cluster on the gauges.

Hmm. I thought the opposite. If the car was able to run after releasing the key from start mode, the voltage must pass through the ballast resister to step down the voltage to the coil so the resister must be working, no?

You are correct, getting old sux, lol

Mopar engineers designed a ballast resistor bypass circuit when they switch from 6 Volts to 12Volt sin 1956, the ignition switch has two 12V feeds into the ignition circuits, one to each side of the resistor so it will start quicker with 12V. feeding the coil in the start position and then run on the voltage coming out of the resistor with the key in the run position
You're not the first one to run into this, trust me

Thanks. Anyone want to take a guess at why the gauges take 5-10 minutes to start working?

When you start the car and it is running, quickly take a test light and check the voltage at the temperature sensor stud with the sensor connected. It should be flashing about twice a second at full brilliance. If not, you still have a problem with the IVR or its connections.

I will check that. If it's not flashing initially, could it be a bad circuit board?

Electrical instrument cluster problems can always be caused by a bad circuit board. But I am a firm believer is going after electrical problems in a systematic approach, not shot-gunning this or that with no rhyme nor reason. This is the place to start with temp/fuel/oil pressure (if equipped) gauge problems.

I'll agree but REFER you to EARLIER POSTINGS






So, let me rephrase my earlier response.
ARE these NEW issues that just appeared or have they been there and or getting worse over time?

ASSuming the wiring is stock, in good condition and not butchered up proceed as follows:

I would recommend using DVM for testing vs. a test light. A DVM will become a good firend once you learn how to use them and they are relatively cheap. One can get by with a test light if you pay attention to the bulb brightness.
Voltage and Current are two different things that interact and you need both for a circuit to function.
I would strongly recommend solving the start issue first. I would also recommend leaving everything in the circuit hooked up for the initial test.
If you have voltage at the start terminal of the ignition switch but not at the engine side of the BH, your problem is likely a connection between the two causing a loss of voltage or the ability to pass current.
If you DO NOT have voltage or weak voltage at the start terminal, replace the switch.
You can also Disconnect the bulkhead and repeat the test as something maybe drawing the voltage/ current down. However that's a bit of a long shot as there are only two things active, 1. is the start V to the coil 2. woul d be the starter relay. A 3rd could be power to electronic ignition if so quipped

As stated previously the gauge issue may or may not be related. 1 step at a time starting with the easiest first. In my 50+ years of experience, I would suspect the Ign switch as you say they operate fine in the accessory position. The IVR, circuit board, wiring etc. don't know which position the switch is in, BUT they work in accessory. there MIGHT be a clue there but not necessarily. Welcome to the world of ELECTRONS. they are fussy little SOB's that have driven more than one person to the looney bin.

On a side note: I don't seem to recall the gauges being operational in the accessory position ? maybe another can clarify that as if they are not supposed to be that would add another issue to the quandary

It could be a myriad of things. But checking for voltage at the sensors, oil pressure, temperature, and fuel level tells you three things, 1) the IVR is working, 2) the dash gauge is not burned out, and 3) the wiring through all the components other than the sensor is intact. This is the most direct way to troubleshoot gauges of this era. In this case if it takes 10 minutes for the gauges to respond after an engine start, doing this check immediately after the engine starts will point the way to the next phase of trouble shooting.

TPJ - Lots of good info here. The wire harness is stock except the amp meter bypass that everyone is doing these days (see attached method I chose). In accessory mode (turn key to left) , my fuel gauge starts moving and if warm, so does the temp gauge. I'm heading out for a long needed vacation but will return in a week and report my progress.

Sounds like somehting is cross wired.
According to the FSM the instrument cluster gages get power from wire G5 - which comes from the run terminal on the key switch. In other words, there should be no power to gages with key in accessory.
Since there is also the starting issue, might be worth disconnecting the key switch and testing the continuity is correct in each position.

Good point. I've only owed the car for about 2 months so I'm not exactly sure what's going on beyond the Amp meter bypass which is relatively simple. The gauges behaved the same way before the bypass so not related IMO.

As stated, someone crossed something somewhere and when Bubba's been there it can be a challenge to figure out as he's pretty good at hiding his cr-p. AMHIK.
I would start by pulling the front seat as your likely to have some time under the dash Do keep us posted

Just got back from a trip to Cape Cod and I'm going to roll up my sleeves and solve this mystery this weekend. Fortunately I was in the middle of replacing my carpet so I should have easy access to the harness. I'll report back on my findings.

Keep us posted

Ignition switch is apparently part of the problem. No voltage passing through the IGN 2 lug on the switch (Brown wire to ballast) so I need to replace that. I also hooked up a test tight to the temp sensor lead at the front of the block. When turning the key to ACC, the test light flashes but it doesn't when the key is switched to IGN 1. Looking under the dash, everything appears to be stock and in its proper place with no apparent splices. The IGN1 circuit to the dash eventually starts working after 5-10 minutes so maybe a bad circuit board ground? On a '69 Charger, how is the dash/ circuit board grounder?

Mattax, I traced the G5 wire (referred to as P4 18DBL* on 1969 Charger Wire diagram) and it goes to the brake warning lamp. See attached. Looks like the 12V dash feed comes from the Black Wire node splice, no?

I believe the cluster grounds through the screws holding it to the dash.

Studying the wire diagram a bit further, I don't see how the Dash gets 12V from the IGN-1 key position unless IGN-1 grabs its 12V source from the ACC circuit inside the ignition switch. is that correct?

Thanks. I'll try running separate ground to the dash and see if that helps.

The accessories are fed from the ACC terminal on the ignition switch. That is energized in the ACC and Ignition 1 positions of the switch. You are correct, the master splice of the black leads from the ACC terminal are the feeds to virtually everything in the car that isn't individually fused.

I find it interesting that you said "When turning the key to ACC, the test light flashes but it doesn't when the key is switched to IGN 1. Looking under the dash, everything appears to be stock and in its proper place with no apparent splices. The IGN1 circuit to the dash eventually starts working after 5-10 minutes so maybe a bad circuit board ground?".

In this 5-10 minutes do any of the other accessories like the windshield wipers and turn signals work? That would prove if the splice is being energized initially. I am assuming that initially the test light does not flash when the key is in IGN 1. I do not think it's a ground problem. If it were a ground problem the IVR would not be functioning in ACC.

6Pak - With the ignition switch hanging down under the dash, I was able to jiggle and push/pull the harness plug in the back of the switch and got the test light to flask in IGN-1 position. More evidence there is an internal short or something going on with the switch. Blinkers worked at all times. I see that the 1969 ignition switch is one year only and made of unobtainium. Classis Industries sells a reproduction switch made by Max Performance. Anyone have any experience with these?

Are the wires in the harness in the plug in good shape? Sometimes a burnt or expanded terminal will cause issues.

I'm so sorry. My mistake. I was looking at the Coronet diagram.
Correct. G1 (Gage) is supplied from the splice in the accssory circuit.
And you can confirm that by the wire colors you see on your car - since occassionbally there were mistakes in the diagram.



Correct.

According to the diagram, G1 gets power when the key is in either Run or Accessory. Powering the gages with the key in accessory seems a little odd to me, but that's what the diagram is showing.

Ignition switch is apparently part of the problem. No voltage passing through the IGN 2 lug on the switch (Brown wire to ballast) so I need to replace that. [/quote]
IGN 2 terminal is only powered with key in Start.




That would indicate the IVR is working. At least its working in the sense that when current flows through, the bimetal heats up and opens the circuit briefly.
When you did that the temperature gage should have moved. My guess is the test lamp has low resistance - like 1 ohm. if so the gage should have pegged hot.

Going from memory, 10 or 12 ohm resistor would be the equivalent of hot, Something around 23 ohms is midway, and 70ish ohms should just move the needle to first mark.

If you're testing for any length of time, at least have 10 ohm resistor. This will protect the heating wire in the gage.

I agree.

Ignition 1 is the Run circuit. It powers circuits to keep the car running. Generally that's the ignition coil, the alternator's rotor (field circuit), and the gages (although not in this case). Accessory is generally all of the other circuits that require key; wipers (circuit breaker), heater (fused), reverse lights, turn signals, radio.

Key switch continuity generally is as follows:
Key off: J1 (BAT) has no connection to anything.
Key Start. BAT terminal connects to IGN 2, and Start.
Key Run. BAT terminal connects to IGN 1 and Acc.
Key Acc. BAT terminal Connects to Acc.

I know with A-bodies 1969 had a one year only switch, but as far as we can tell the terminal positions and function were the same.
This is probably a good case to verify the drawing with what you see on the car.

There is something odd here. The turn signals are fed with wire D1-18BK from the master splice. The IVR for the gauges is also fed from this master splice on wire G1-18BK. How can one work initially without the other? The gauge issue seems to be changing to an instrument cluster problem. I would once more recommend checking the voltage at the temperature sensor immediately when the gauges are not working. If your test light doesn't flash, I'm going to put my money on the IVR. How do the wipers respond initially?

So I went back and double checked. You are correct. The blinkers work with key in IGN-1 position ONLY when I jiggle the ignition switch/harness plug. The blinkers work at the same time I get the temp gauge working in IGN-1 position and they both stop working together. I've yet to check the wipers.

Ah ha!!! It sounds like you have isolated it to the switch. It still seems odd that initially it won't work but after a number of minutes it will. I am struggling with what can cause that. But as Thoreau put it regarding a trout in the milk, what you have is what you have. Good job!

Could also be a bad crimp/connection
As for the warm up time, excessive resistance, again switch or connection.
I would first inspect that terminal and crimp very thoroughly, post a pic if you'd like

if it is in fact the switch, the Contacts inside the switch may need cleaning, which can only be done by disamrling it or using a contact cleaner Like Deoxit. It will be hard to get inside unless one drills a small hole or soaks it. It helps to actuate the switch multiple times while the cleaner is inside.
If soaking I would do so in a closed container O/nite then set it in the sun or a warm environment to allow the solvents to evaporate before using it as i believe they are flammable.
It's possible the switch is worn beyond use. But I, again would inspect that terminal first

What is still puzzling is the car will run but the gauges etc. are flakey. Do they not both feed off IGN 1 ?
Also no V to the coil from Ign 2 in the start position but the starter relay engages? Are they also both not fed from the same terminal?

Those are definately possibilities.
I'd go with a trust but verify approach.
1. Remove the connector from the key switch. Check continuity from B to the other terminals with key in every position. Using resistance setting on the multimeter would be best.
2a. Check for continuityand wire colors between the connector cavity that matches I1 and the G1 wire terminal at the board.
2b Check for continuity and wire colors between the connector cavity that matches A and the G1 wire terminal at the board.


Once the wiring is sorted out, that shoudl take of the starting issue and hopefully also the gages.
But if the gages still have an issue, even though the other 'accessory' are working immediately, then its probably a connection on the board.
This is an instance where the voltage can read OK during testing, but doesn't reveal resistance. The resistance only shows up as a voltage loss whith sufficient current flowing through,
This can happen with the main feed as well, in particular with the 'MAD' approach. The battery is first in line from the alternator output. That could make the battery the path of least resistance back to the alternator's ground. If the distance and resistance to the rest of the circuits is long enough, high enough, then they don't get the full power until the battery is recharged.
I don't think that's what's happening here. The switch or its connections seem to be the culprit, or at least the main culprit.

Agreed on the continuity / resistance tests, but want to make the OP aware that one can show little to no resistance with a meter and NO LOAD on the circuit / dervice. But it may not be able to pass enough current through the switch /terminal/wire for the load, which would then cause a voltage drop due to the resistance. Aren't electrical problems FUN ???

electrical problems are the reason there is no hair on the top of my head.................

Hmm. Electrical engineer for nearly 50 years, PE for forty of those, I still have lots of hair on top of my head.....even though it's now all white.

TPJ - Good input but at this point, I'm going to replace the switch. It's 53 years old and don't want to risk a short while driving.

I'm getting fluctuating OHM readings in the IGN-1 position. I'm also getting fluctuating readings in the IGN-2 position as well. Switch has been ordered.

Absolutely.
Its always a balance between enough info to get to the next step or two, and too much info and it becomes unreadble or just overwhelming..
I figured the main objective was looking for the continuity results, and secondary was looking for large (by which I mean measurable) resistances.

I still don't fully trust the wiring diagram. Having the gages working while the key is in accessory is an outlier. As far as I know the main use of acc position was/is to listen to the radio without burning fuel, and without cooking the coil.

I agree100% as well as adding more drain to the battery Seems strange and I don't recall any gauges working except the ammeter in Acc.

While waiting for the switch, Inspect the crimps, terminals, and verify that they are ALL properly placed in the correct connector slot

Will do!