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Gauges not working on my 74’

74bronk

Full Member
Joined
Sep 1, 2004
Messages
301
Been putting my Bronk together and got it running last couple of years. Sent out my gauges cluster had it refurbished. I also had the the dash board “powder coated” front and back, wondering if this is the issue? I can get the dash lights to work speedometer works I just can’t get the fuel gauge to function (most important to me) does seem that the oil pressure gauge does work other 3 do not. I know they all work because I was working on another problem someone move something under the hood or I did something in the cab and the gauges all started to work for about a minute. Getting a little frustrated. I even ran a special ground specifically to ground all gauges. It is getting voltage and regulator on cluster is good. Any help appreciated.

Thanks
 

Brush Hog

Contributor
New Member
Joined
Mar 16, 2022
Messages
23
Is your dash grounded? Needs to be grounded to bare metal. Just grind off small spot of the powder coating that’s what I had to do. Then attached ground wire from dash to windshield frame.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
44,404
Yep, powder coating is the bane of the existence of new wiring on an old vehicle.
You should run at a minimum:
1. Ground wire from the battery to body (in addition to the normal one to the engine).
2. Ground wire from the back of the engine to the firewall.
3. Ground wire from firewall or other body part to the dashboard.
4. Ground wire from the dash to the instrument cluster itself. Without a good ground connection your gauges will not work properly.
5. Make sure that the instrument cluster housing was not painted. If it was, then make sure that the IVR (instrument voltage regulator) is grounded to the housing. Or it won't work...

It's also not a bad idea to check the input of the IVR to make sure that 12v is getting to it reliably, and that approx. 5-6 volts is getting out of it to the gauges.
Is this a stock IVR or an electronic replacement?

And you didn't say, so we can only assume that you also re-wired the entire vehicle. If so, what harness did you use?
And either way, new or old wiring, did you make sure to put the body ground back in place? When you moved something under the hood and they worked for a bit, I wonder what you were messing with or bumped?

So more details please. And maybe even some pics.

Good luck.

Paul
 
OP
OP
74bronk

74bronk

Full Member
Joined
Sep 1, 2004
Messages
301
Yep, powder coating is the bane of the existence of new wiring on an old vehicle.
You should run at a minimum:
1. Ground wire from the battery to body (in addition to the normal one to the engine).
2. Ground wire from the back of the engine to the firewall.
3. Ground wire from firewall or other body part to the dashboard.
4. Ground wire from the dash to the instrument cluster itself. Without a good ground connection your gauges will not work properly.
5. Make sure that the instrument cluster housing was not painted. If it was, then make sure that the IVR (instrument voltage regulator) is grounded to the housing. Or it won't work...

It's also not a bad idea to check the input of the IVR to make sure that 12v is getting to it reliably, and that approx. 5-6 volts is getting out of it to the gauges.
Is this a stock IVR or an electronic replacement?

And you didn't say, so we can only assume that you also re-wired the entire vehicle. If so, what harness did you use?
And either way, new or old wiring, did you make sure to put the body ground back in place? When you moved something under the hood and they worked for a bit, I wonder what you were messing with or bumped?

So more details please. And maybe even some pics.

Good luck.

Paul
Yes wiring was replaced about 10 years ago. I do need to add all those grounds the IVR should be new when I ordered a referbished cluster along with the gauges
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
44,404
I was thinking you had a new harness when you said the lights worked. The aftermarket harnesses have separate grounds for the lights, illuminating the dash.
Whereas the factory relied on the dashboard to ground.
 

sprdv1

Contributor
REBEL
Joined
Mar 8, 2007
Messages
80,465
Yes wiring was replaced about 10 years ago. I do need to add all those grounds the IVR should be new when I ordered a referbished cluster along with the gauges

maybe time for new? I guess it could still be okay tho
 
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