• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Which Instrument Voltage Regulator for a 66 Coronet 500?

Nxcoupe

Nxcoupe

FBBO Gold Member
FBBO Gold Member
Local time
9:35 AM
Joined
Jul 4, 2021
Messages
3,176
Reaction score
4,733
Location
Red Lion, OH
I was just on RTE's website and a 1966 Coronet was not on either list for an IVR3 or IVR4, anyone know offhand which one to use? I feel like it's a good upgrade whether it's my issue or not. I need to get my gauges working properly if I'm going to drive this to Carlisle. I really don't want to trailer it. Any help is appreciated. Also, any links to a good tutorial of how to remove the cluster would also be of help as I need to get the radio functioning as the LED comes on, but I get no sound, so I'm assuming the speaker passed on to a better life.
Also want to ground the cluster, anyone do that on a coronet and have advice or pics?
Thanks!
 
Classic Industries shows a factory style as this one :
https://www.classicindustries.com/product/1966/dodge/coronet/parts/ivr607.html
RTE's site shows the IVR4 which has same appearance and similar connections, but is much better and solid state. You could also E-mail RTE for an opinion on the suitability for your car.
On your radio, before you assume that speaker is bad, you can easily test it when disconnected from the radio.
With a multi meter set to ohms Rx1, or a 1.5 V battery. Very quickly, touch speakers terminals across the battery or meter leads. You should see some resistance on the meter. Don't leave either mater or battery connected !
Either way you should hear a thump from speaker if it's good. Can't help you with how to get the cluster out..
Keep in mind that if your factory regulator went defective and applied full battery voltage to the gauges, it's likely that it may have damaged your temp, oil pressure and fuel gauges which are all sourced from the 5V output of the regulator. .
 
Last edited:
Although you won't get the waveform replication of the original IVR, you can do the simple LM7805 regulator with three capacitors. Heatsink the LM7805 to the frame of the cluster. Lots of "how to" blogs out there on various ways to mount the regulator.
 
Basically, the factory regulator is a thermal device that reduces the voltage via a resistive, or resistance wire. This wire is wound on a bi-metal strip. When the strip is cold, it has closed "points" and it applies near full battery volts to the gauges to get them to rapidly provide readings. Shortly after that full voltage is applied by the regulator, the resistance wire heats up the bi-metal strip causing "points" to open in short order. It will then cycle mechanically, continuously opening and closing the points providing a "pulsating" and reduced voltage to the gauges of approximately 5 volts, NOT a continuous 5 volts. You don't see the pulsation on the temp, fuel and oil pressure gauges due to the electro mechanical design of the 3 gauges which causes a "hysteresis" type effect. The gauges themselves operate in a similar thermal manner with bi-metal strips, but do not have "points". The resistance wire is wound on a bi-metal strip that depending on it's temperature controlled by current flow thru it, mechanically moves the pointers. The regulator's output is fed to the 3 aforementioned gauges. Current flow thru the gauges is controlled by the resistance of the respective senders which are basically variable resistors to ground that complete the electrical circuit for each gauge.
The RTE voltage limiter, or regulator, provides similar operation as the factory units did, but do it electronically with much more accuracy and reliability with a robust solid state design. IMHO, you really want to get the RTE unit. It was one of the first things I changed out when I got my Charger in 2010, been working flawlessly ever since. Hopefully your gauges are still OK and not fried due to having full battery voltage applied to them. This can happen when the mechanical regulators points stick closed applying a continuous full voltage to the gauges. Good luck with it...
 
RTE recommended one for my 66 Satellite which should be the same as for your 66 Coronet. Give them a call.
 
AR67GTX said:
RTE recommended one for my 66 Satellite which should be the same as for your 66 Coronet. Give them a call.
Click to expand...
I looked on their site, found no phone number and the email address I found was returned to me as not a valid address.
Which part number did they recommend? If you have contact info or I missed it, please share.
 
twecomm said:
Basically, the factory regulator is a thermal device that reduces the voltage via a resistive, or resistance wire. This wire is wound on a bi-metal strip. When the strip is cold, it has closed "points" and it applies near full battery volts to the gauges to get them to rapidly provide readings. Shortly after that full voltage is applied by the regulator, the resistance wire heats up the bi-metal strip causing "points" to open in short order. It will then cycle mechanically, continuously opening and closing the points providing a "pulsating" and reduced voltage to the gauges of approximately 5 volts, NOT a continuous 5 volts. You don't see the pulsation on the temp, fuel and oil pressure gauges due to the electro mechanical design of the 3 gauges which causes a "hysteresis" type effect. The gauges themselves operate in a similar thermal manner with bi-metal strips, but do not have "points". The resistance wire is wound on a bi-metal strip that depending on it's temperature controlled by current flow thru it, mechanically moves the pointers. The regulator's output is fed to the 3 aforementioned gauges. Current flow thru the gauges is controlled by the resistance of the respective senders which are basically variable resistors to ground that complete the electrical circuit for each gauge.
The RTE voltage limiter, or regulator, provides similar operation as the factory units did, but do it electronically with much more accuracy and reliability with a robust solid state design. IMHO, you really want to get the RTE unit. It was one of the first things I changed out when I got my Charger in 2010, been working flawlessly ever since. Hopefully your gauges are still OK and not fried due to having full battery voltage applied to them. This can happen when the mechanical regulators points stick closed applying a continuous full voltage to the gauges. Good luck with it...
Click to expand...
The original Mopar IPVR is a, simply stated, a mechanical percent cycle timer......with 12 volts DC applied (approximate), the IPVR opens and closes its internal contacts to yield 5/12 on time to net ~ 5 VDC (approximate) average output to supply the instruments. The electronic IPVR is superior and more accurate, plus it offers protective circuits to prevent individual instrument damage due to short circuits.......just my opinion......
BOB RENTON
 
Found this on the web site listed as contact info. Many small businesses have E mail attached to / as the web address.
Real Time Engineering
19352 Hilton Rd.
Springdale, AR 72764
http://www.rt-eng.com
 
twecomm said:
Found this on the web site listed as contact info. Many small businesses have E mail attached to / as the web address.
Real Time Engineering
19352 Hilton Rd.
Springdale, AR 72764
http://www.rt-eng.com
Click to expand...
Yeah, I appreciate that but it's a link to their pitiful site and no phone number.
 
twecomm said:
Classic Industries shows a factory style as this one :
https://www.classicindustries.com/product/1966/dodge/coronet/parts/ivr607.html
RTE's site shows the IVR4 which has same appearance and similar connections, but is much better and solid state. You could also E-mail RTE for an opinion on the suitability for your car.
On your radio, before you assume that speaker is bad, you can easily test it when disconnected from the radio.
With a multi meter set to ohms Rx1, or a 1.5 V battery. Very quickly, touch speakers terminals across the battery or meter leads. You should see some resistance on the meter. Don't leave either mater or battery connected !
Either way you should hear a thump from speaker if it's good. Can't help you with how to get the cluster out..
Keep in mind that if your factory regulator went defective and applied full battery voltage to the gauges, it's likely that it may have damaged your temp, oil pressure and fuel gauges which are all sourced from the 5V output of the regulator. .
Click to expand...
Thanks, I am going to pull it apart and document my journey with it on my coronet thread. I believe the radio is working because the LED changes color and intensity when tuning and turning it on and off, as that is how you change inputs.
 
A little more visualization in support of my previous rambling on how they work...
A pix of the guts of a gauge limiter / regulator...

Screen Shot 2025-06-05 at 8.04.25 AM.png
 
You must log in or register to reply here.

Similar threads

icetech
Which solid state regulator for a single field?
2
Replies
34
Views
2K
icetech
icetech
twecomm
Gauge voltage regulator.. how does it work ?
Replies
2
Views
487
RJRENTON
RJRENTON
Maus
Voltage Limiter location and disassembly
Replies
18
Views
2K
Maus
Maus
R
Voltage Regulator Condensor wiring
Replies
4
Views
1K
Sinitro
Sinitro
kaj750
Voltage regulator?
Replies
10
Views
2K
kaj750
kaj750
Auto Transport Service
Back
Top