No power to gauge cluster?
 

Been reading the forum for a few hrs now trying
to gain some insight as to why my gauge cluster isn’t working on my 67 (I’m pretty amateur at this side of things). Fuel gauge worked when I bough the truck 6mo ago but is now stuck at about 1/2 tank, temp gauge did not and still does not work (pegged at low) and ammeter didn’t and still does not work. All lights,blinkers, etc do work on the truck.

I found that I have no power going to any of the pins on the main cluster plug. I do have power on the LH side of the fuse holder for cluster, but not on the right side with a good fuse in place. I hooked alligator clips to each side of the cluster fuse holder tabs and turned the key to check for power to the cluster plug pins and there was still none. What would be the next thing to check to locate power or a break somewhere? The terminal is pretty corroded and I did try cleaning it up with no changes.

I have a suspicion that when I get power going to the cluster, my gauges will likely work (based mostly on what I’ve been reading along with my fuel gauge working before and there’s not much to the temp gauge/sender troubleshooting process). Also p/o said the truck has new OE fuel tank and sender.

Re: No power to gauge cluster?
 

If you have power on left side of fuse and none on the right, it is either a bad fuse or a bad connection. What do the fuse holders look like? If rusted, take some sandpaper or small wire brush and clean them up good. Take the fuse out and test it for continuity from one end to the other. Put a good fuse in and then you’ll have power on both sides and can keep chasing connections if this doesn’t fix the issue. If one of your fuse holders is rusty, they probably all are. Take some time and clean them all paying attention to the size of fuses indicated and making sure the fuse size matches the slot. The fuse box can be loosened without disconnecting wires to help with access. Good luck.

Re: No power to gauge cluster?
 

The fuse holders are pretty rusty. I went in and cleaned that specific one with my dremel. I only had a 10a fuse handy in the garage so I put that in with the same result (no power across the fuse). I’m picking up some 3a after work today. Then I tried just jumping from one side of the fuse holder to the other with alligator clips, but still got no power to the cluster (or the unfused fuel slot if that’s supposed to be hot). I’ve never taken apart a fuse panel block before but I’m thinking there’s a rusted/broken connection for that fuse as I’ve got power from the ignition to the fuse panel. I guess next step is to try and remove the fuse panel, check it out and clean it up. Eventually I’ll get a harness kit and redo the whole thing but it’s not in the cards right now while opening up a new business : )

Re: No power to gauge cluster?
 

Here are a couple of threads you may find useful info in.
Instrument cluster, gauge type
http://67-72chevytrucks.com/vboard/s...d.php?t=709847
fuse panel
http://67-72chevytrucks.com/vboard/s...d.php?t=741245

Which fuse are you checking? I had trouble testing for voltage through the rust, but if you stab the voltmeter or tester into the fuse end cap and fuse holder you should get a reading. The fuse outlined in purple in the picture below is the one that should have power in the key on position.

Check for voltage on the pink wire at the instrument cluster. With key in on position you should be getting power on that wire.

Are your instrument cluster lights working? How about the turn signal lights on the instrument cluster? Does the brake light come on during start?

Is your instrument cluster plug have the wire colors in the correct spots on the connector? I ask because the non-gauge cluster has different wiring at that plug.

Re: No power to gauge cluster?
 

The purple square labeled ‘key on’ was the area that I tested. Test light lit up when I placed it on the side near the ‘3a’ on the photo but not on the opposite side of the fuse near the ‘clst’ letters. I put in a new fuse with same results. I also attempted to jump across the fuse connectors with alligator clips- still no power to any of the pins on the plug with the key on. With the key on I have no power to any of the pins on the main cluster plug (the plug closest to the ignition). All of my lights, blinkers and dash lights work. I matched the plug to the photos from my search and everything appears to be accurate for the gauge style cluster. It’s like power just terminates at that fuse but I’m not sure what the connection behind the panel looks like or if maybe something just has that bad of a connection. I did try cleaning the fuse holder with my dremel but it didn’t make a difference. I’ll check out the threads you posted, thank you!

Re: No power to gauge cluster?
 

Well if you're getting power on the input to the fuse, but not on the other side of the same fuse, then the fuse is bad or the jaws that grip the fuse are too rusty. I can't think of another explanation. It is possible for new fuses to be bad, and bad fuses to look good through the glass.

Re: No power to gauge cluster?
 

Hopefully I’ll have a chance to check into it a little more today after work, thank you for the reply. I’ll start with trying to get in and clean the fuse holder a little better and then go from there.

Re: No power to gauge cluster?
 

Well the good news is I’ve got power to the cluster and confirmed fuel and temp gauge both work (although temp gauge not connected to sender). Bad news is that there’s a wire jumped from the ignition unfused terminal to what looks to be a broken off fuse holder behind the fuse panel (held together with a modified spade connector lol) with about zero room to repair as it sits. Power to the fuse panel (or most circuits anyway) cuts in and out when the wire is moved due to a bad connection.

How hard is it to pull the fuse panel away from the firewall and is there any slack at all in the wires that might allow me enough room to make a repair? There’s not a lot else that looks non-factory so if I can get behind to repair that connection I’m pretty sure I can get by until I tackle a new harness kit or at least do a fuse panel upgrade.
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Re: No power to gauge cluster?
 

I have removed the couple of screws that hold the panel to the firewall and I don't remember it being very hard, but it has been a while. The hardest part is just being under the dash. When I'm going to spend any significant time there I like to remove the seat. There is not a lot of slack in the wire bundles. It depends on how much you want to get into it. You can unwrap the wire bundles and re-wrap them later after a repair using the same tape or new non-adhesive vinyl tape. I bought some non-adhesive vinyl tape on amazon.com. I normally use solder and shrink tubing to make repairs. I have bought parts and pieces of wiring harnesses from people here on the forum before, by making a want to buy ad in the parts forum. I'm sure there are a lot of people here who have their old wiring harnesses on hand after re-wiring their trucks. You may be able to get a fuse box that is in better shape than yours or which has some terminals in it that are in better shape, or you may be able to connect into the wiring harness and skip the fuse in the fusebox and wire in an in-line fuse holder for that pink wire that goes to the instrument cluster. The fancy way to deal with this is to buy a complete dash wiring harness from a vendor, some are made that are just like the original, and some use newer blade style fuses. I recommend make sure you are using a fusible link wire at the battery connection, that is all that protects the 12 gauge wiring in the truck.

Re: No power to gauge cluster?
 

Thank you that’s excellent info. I was thinking the same thing on method of repair of existing but it didn’t even cross my mind to seek out a good used fuse panel. Those wiring kits look great but pretty expensive and as long as my truck is safe and working, that’s all I’m really concerned with for now : ). Someday I’ll probably do a more extensive restoration but for now it’s just a cool old truck to cruise around in : ). Thanks again for the help, I think I’m on the right track now
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