Lights don’t dim with more electrical devices on?

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Phil21502

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So my 74 darts headlights and instrument lights flicker at idle and while going down the road but if I turn my electric fan on they are perfect? It’s on a manual switch. Is this weird to anyone else? I would think it would be the opposite.
 
Hmm. Read on here about adding a jumper wire from blue wire on voltage regulator to the battery stud on starter relay. Is this worth doing?
 
also look at bulk head connector. pull a part coat with silocone grease. a mopar trait. you may also look 4 any nasty corrision on any connector.
 
best ck grounds. batt first have u worked on recently or any repairs. u keep it clean? no but realy flasing is vreg any elec or old. ck connections..cheaper
 
sorry usaid don't dim mopar that's great. no but look as I advised. post Batt or what u may have done a connection or er
 
Elec fan? Aftermarket then, I would check connections related to the fans 1st and go from there.
You best carry a fire extinguisher....I do.
 
Connections are all good. Just installed an MSD Ignition too and I’ve double checked those wires too. Grounds have all been cleaned checked and re installed. Now to think of it I did install a new voltage regulator from the parts store last week. Factory one seemed fine just looked rough and I’m on a mission to clean up the engine bay. I’m gonna try putting the factory one back in and see what happens.
 
Mine did this, even after i bypassed the bulkhead and ran charging current directly to the battery, until I replaced the instrument cluster regulator with a solid state one. You can buy them or make them easy enough. I made mine and that fixed it.
 
until I replaced the instrument cluster regulator
IMHO it was coincidental....Unless the instrument cluster in a 74 is VERY different than a 67 (yes I know it is physically different, I mean electronically) the instrument cluster regulator ONLY feeds the fuel gauge and the temp gauge. The instrument panel lights are 12 V and get their power from the dimmer in the headlight switch. so changing to a solid state instrument voltage regulator would have no effect on the dash lights AND the headlights as the OP stated.
 
Have you done a voltage test or a charging system test?
 
Now to think of it I did install a new voltage regulator from the parts store last week. Factory one seemed fine just looked rough and I’m on a mission to clean up the engine bay. I’m gonna try putting the factory one back in and see what happens.
That would be a great first step.

I would also take car to parts store and have them test the alt, especially for bad diodes. (free and easy)

My 67 would (while sitting at a light) wiggle the AMP meter. I had the alt tested and they reported bad diode. I replaced it and the wiggle is gone.

The diodes convert the AC from the alternator to a form of DC and if diodes are failing the DC is less DC which can result in a flicker etc.

BUT my bet is on the voltage regulator, especially if you did not notice it before the change but notice it now. If that is not the case and it happened before then I would focus on the alternator.
 
That would be a great first step.

I would also take car to parts store and have them test the alt, especially for bad diodes. (free and easy)

My 67 would (while sitting at a light) wiggle the AMP meter. I had the alt tested and they reported bad diode. I replaced it and the wiggle is gone.

The diodes convert the AC from the alternator to a form of DC and if diodes are failing the DC is less DC which can result in a flicker etc.

BUT my bet is on the voltage regulator, especially if you did not notice it before the change but notice it now. If that is not the case and it happened before then I would focus on the alternator.
And make sure the regulator case is grounded well to raw metal on the firewall. You need star washers or even a separate ground strap to make sure. A lot of people have charging system issues after new parts and/or firewall painting. Get a regulator from your Mopar dealer. I believe they are still available.
 

Will run some voltage tests here when the rain quits. The joys of no garage. Gonna go ahead and get a new negative battery cable and terminal as my terminal looks a little worse for ware. Thanks for all the info
 
While I’m waiting on the weather what are everyone’s thought on adding a larger ground wire from battery to core support?
 
IMHO it was coincidental....Unless the instrument cluster in a 74 is VERY different than a 67 (yes I know it is physically different, I mean electronically) the instrument cluster regulator ONLY feeds the fuel gauge and the temp gauge. The instrument panel lights are 12 V and get their power from the dimmer in the headlight switch. so changing to a solid state instrument voltage regulator would have no effect on the dash lights AND the headlights as the OP stated.

The power from that regulator only feeds those two items but you have to understand how the regulator works. The regulator is dumping power 7/12'ths of the time, to provide 5V for the instruments. The electromechanical regulator is literally grounding itself, repeatedly, all the time, and the grounding is causing the load variations in the charging circuit.

It is the same principle as the vehicle regulator, and the same net result when that is replaced with solid state, which does not fluctuate at all.

AND your gauges will be more consistent.
 
The regulator is dumping power 7/12'ths of the time, to provide 5V for the instruments.
I have to disagree with you. the regulator is not dumping power to ground it is opening the cir so no flow of current

The electromechanical regulator is literally grounding itself, repeatedly, all the time,

The instrument panel voltage regulator has a heater coil that heats bi-metal and it opens and closes (like a flasher) the 12 volt from the battery to the gauges resulting in a pulsed DC with an average voltage of ~5V





causing the load variations in the charging circuit.
I agree that like a blinker when the connection is made there is more current draw and a dimming of bulbs can result BUT the gauges do not draw very much current and if you have headlights and instrument cluster lights flashing from the Fuel and Temp gauge you have some other BIGGER problem.
 
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I have to disagree with you. the regulator is not dumping power to ground it is opening the cir so no flow of current



The instrument panel voltage regulator has a heater coil that heats bi-metal and it opens and closes (like a flasher) the 12 volt from the battery to the gauges resulting in a pulsed DC with an average voltage of ~5V






I agree that like a blinker when the connection is made there is more current draw and a dimming of bulbs can result BUT the gauges do not draw very much current and if you have headlights and instrument cluster lights flashing from the Fuel and Temp gauge you have some other BIGGER problem.




OK, how about this.

I replaced my IM regulator with solid state, and 9 years later Trump got elected, but the Russians fixed my flickering lights 9 years prior via a magic communism ray, and it was just a ******* coincidence that my **** stopped flickering at the exact moment that I replaced the IM regulator.

Does that ******* work for everybody in this ******* thread? Jesus mothertrumping Christ. OP, everyone else, try the **** or don't, but my lights flicker worse on my Neon than they do on my Dart, and both cars are better than yours.
 
Nah. 2morro should finally clear up around here. Or start that is everything I’d like a swamp
 
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