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1970 Standard Gauge Cluster circuit board question

signalsparks

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Question first: Can anyone verify whether the '68-'70 NON-Rallye gauge cluster circuit board has diodes and capacitors on it or not? IF they are normally there, what are the values on the diodes?

*Edit* I figured out this array of components must be a substitute for the voltage limiter device found on stock circuit boards. I have a new circuit board and voltage limiter on the way from Y1 now.

Background:

So I think I may have had a bit of a water puddle on my fuel sending unit, and the previous owner of my car put ALL 20A fuses in the fuse block... It smoked, then the fuel and temp gauge quit working.

I finally got the time and the good weather so I pulled my dash apart to see what was going on. Figured I blew a trace on the gauge circuit board and a little time with a soldering iron would straighten that out.

Lo and behold, the circuit board was a retrofit, screenprinting says "Charger Specialties CQ2" and it has a curious array of a couple diodes, 2-3 capacitors, and a rectifier of some sort soldered to the board behind the fuel gauge. At least one of the diodes is completely blown. I can still read the values on the caps, but no clue on the diodes. They're crispy.

Charger Specialties is out of business, assets purchased by what appears to be a Mopar junkyard in Georgia that has a perpetual busy signal on their phone and has not yet returned my email inquiry.

I noticed Classic Industries's replacement board has no such components. Could be an inaccurately assigned photo, not sure.

Any guidance would be helpful. A Mouser or Digi-key part number would be AWESOME. I could take it from there and get back on the road... I'll be changing the gauges fuse while I wait, and probably put an inline REALLY low-amperage fuse inline on both sending units.

336682930_212850454722147_8297166764344838917_n.jpeg
 
Last edited:
That is an aftermarket board with an incorporated voltage limiter for the gauges.
 
That is a kluge using a LM7805 and a few capacitors. Electrically okay with a good heatsink, but I prefer the rt-eng.com limiter.

Member @Nacho-RT74 will guide you thru the repair.
 
That is a kluge using a LM7805 and a few capacitors. Electrically okay with a good heatsink, but I prefer the rt-eng.com limiter.

Member @Nacho-RT74 will guide you thru the repair.
THANK YOU for the part number! I'll see what I can grab and solder up. Maybe as a backup.

Unfortunately I've been blackballed from Paypal since 2003 so I can't buy that rt-eng device, but it looks nice.

I purchased something legit from a site that apparently sold something not-so-legal (no idea what) for the exact same price. Paypal limited my account. No avenue for appeal/recourse. Just two years ago they 'found' my Venmo account after I'd had it for 2+ years and closed that, too. They're NOT subject to FDIC regulations; they're not a bank, they make their own rules. Unless I simultaneously change my address, email address, bank accounts, and credit cards (which will trash my credit!), I'm screwed.
 
That is a kluge using a LM7805 and a few capacitors. Electrically okay with a good heatsink, but I prefer the rt-eng.com limiter.

Member @Nacho-RT74 will guide you thru the repair.
Yes.....get rid of the installed components and use RT-ENG.com. without a heat sink on the diode array it will overheat and fail. RT's offering has circuit protection. You could call RT ENG and offer to buy using a check or money order.....just a thought....
BOB RENTON
 
You need to either replace the board and get a new limiter or. You could clean the junk off that board and use an external set up like this. More info here MOPAR Products

AbodyRallyeLimiter3.jpg
 
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