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Discussion Starter · #1 ·
Hello, All!
My soap opera continues...
I am installing a Gauge dash in my 70 Chevelle, from idiot lights, I have rerouted wiring in the pin connector has should be from previous responders info & downloaded diagram, but when I plug it in and turn the key I get NOTHING. Fuel, Temp, or Amp, No left turn signal indicator, No high beam light, no low oil light.
HELP, I would like to someday drive this car, at the rate I am going it could be Nov.
 

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Discussion Starter · #3 ·
Yes,& I have power to the #7 Pin on the master pin connector as well?? When I check (use my test light)on the MPC I have all functions.
 

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Discussion Starter · #4 ·
I tried the battery to gauge set-up for bench testing, NOTHING!! (when I installed the dash in the car, at least I had dash lights, turn lights, no left turn light, no hi-beam, no oil), on the bench test the only thing I could get to light was hi beam. Could the PCB be bad??? I ordered new from Grd up? It's getting close to miller time!!

I have traced and traced all that my little brain knows to check??
:eek:
 

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I'd do a quick check with a test light to make sure you have power from the PCB connector since it sounds like you have power to the plug. Check the temp sending unit plug (the one that connects to the sender), fuel gauge plug (at the rear of the car), turn signal, and high beam switch. Are the dash lights working? Is the turn signal bulb grounded in it's socket?

Is the cluster grounded? I had that same problem and found out it was a grounding issue.
 

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Discussion Starter · #6 ·
I know I hate grd, it can always trip a fellow up, As I stated above, I had lights when I had the dash in the car, my problem is that the gauges themselves were not working. I have the dash on my workbench right now, trying to bench test it.
 

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Discussion Starter · #7 ·
Here is a thought, Does all of the dash lights have to be grounded? will this cause the rest not to work?? or if a light is out?? will it not work, seems like when I benchtest I get a very weak light on my tester, and cannot get the lights to come on>>>>>
 

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THe dash has to be grounded. The pod that holds the instruments is metal but it is mounted to a piece of plastic. IF that metal pice is not grounded someplace you are screwed.

These are NOT Christmas tree lights!!!!! One being out will not kill the others.

"seems like when I benchtest I get a very weak light on my tester, and cannot get the lights to come on" Seems like you get a weak like or you DO get a weak light? How were you bench testing this and what were you bench testing for the instrument lights or the instrument functions???
 

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Discussion Starter · #9 ·
In search I have found a method for bench testing and follow it's instructions, I am using a 12v battery out of the car, Fuse in-line on the posi+ side grd to metal part of the cluster?? I think that Grd may be the problem but it's just going to take some time to figure out, I have been working at this for 3 weeks, Thx for your help.
 

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OIL does not use the dash ground.
Do you have 12 volts on the IGN and ACC terminals on the fuseblock. If so, try grounding the blue wire that goes to the oil sender and see if that light comes on with the key turned to ON.
 

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Discussion Starter · #11 ·
Question # 300,00000,00000000,00000.
When I installed a new temp sender unit into the block I used alittle teflon to help the threads, did I screw up , because this needs to ground to the block to work. I am thinking that it will but since I am having sooooo much fun typing these lame questions on the computer thought I would ask!!!!!!!!!


"Lights are on, But! bubba ain't home..."
 

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Teflon is not recommended, in fact it is loathed by the Vette guys. Grounding is all important in Vettes and the teflon can effect the ground and therefore effect the readings on the temp guage. Now understand the Vette guys are a hyper sensitive, more often than not 10 thumbed crowd, who send the cars to "Their mechanic" for the slightest repair. Keep that in mind as I go on.

In the case of the Chevelle I suspect the teflon has little effect but you never know. The only guage that would be effected would be the temp guage when the ground is bad.

Also the senders can be problematic. Again from the ever accurate world of the Corvette Resto crowd...the temp senders made today as replacement parts MAY NOT have the same range of resistance as the originals. When a new (or different) sender is installed the reading on the guage can be altered even if nothing else is changed on the car. The resistance range of the sender as it is exposed to the varying temp of the engine coolant will send different "signals" to the guage head.

The Vette gys correct for the foreign / incorrect senders by wiring a resistor into the lead to the sender. They swap resistors in and out while checking the true engine temp with the IR temp "guns". Once the guage head reads the same as the gun "Accuracy has been estanlished" and it is on to the next resto issue. You don't have a Vette so why do you care about this?

Well you care because depending on the condition of the engine ground on your Chevelle and the ground between the sender and the manifold different "signals" can go to the guage head. Most often this "teflon phenomina" effects the accuracy of the reading as opposed to producing a no reading at all condition.

This really is a relatively simple procedure are you wishing you never started this swap?
 

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Discussion Starter · #13 ·
Pretty much!! (on the last statement)

No, it needed to be cleaned up, as with most things that get your goat, this is not a rocket ship, or engine. I think at this point Iam going to reinstall the dash and snug everything down. If it doesn't work, the next post will be for a nice (less dash) 70 Chevelle SS for sale. ( hahahahaha)

Thx
 
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