View Full Version : Gauge issue, help please!!
Higgybulin
05-22-2020, 03:24 PM
So I'm getting ready to go kart and I am having issues with my gauges. I have the speedhut gauges with a carburated 351C using the Ron Fransis harness ....all the back lights and needles are working in all gauges. That's it though, I can't get any of the gauges to read anything. Even the little LCD display doesn't come on with the key. I can calibrate the clock. I just made sure the main ground wire by the fuse box has a good connection. Any thoughts would be helpful
Higgy
edwardb
05-22-2020, 03:38 PM
Very basic question. I assume you know the needles and backlighting are on a lighting circuit? Which is difference than the gauge power circuit. So the lights could be powered, which obviously they are, and still work even though the gauges aren't powered. There's a gauge power wire in the RF harness. Plus it has a fuse. Have you checked if that wire has +12V and it's connected to the gauge red power pigtail? Ground is obviously something to check as well. One other question. Do the needles swing at all when you turn the ignition on? I'm betting not since you said the LED window in the speedo isn't lit. But if they don't do something at power on, another reason to suspect power wiring. Apparently you have the clock attached to a different always on circuit, which is correct.
Sounds like you're not getting power to the gauges. The lighting circuit is separate from the gauge power.
Dave
Edit: Paul beat me to it.
Higgybulin
05-22-2020, 05:34 PM
Thanks Dave and Paul for the quick replies. I have two gauge feed wires that I can find, one goes to the red wire in the red/blk/wht speedhut pigtail and to each gauge. The other goes directly to the power on my voltmeter. Neither have 12v going to them with the key on. Checked the fuse and its good....maybe a short in the wire harness?
Next silly question...do you have power to any other ACC circuits? I thought I'd fried my gauges at one point only to find I'd wired the ignition with the wrong "brown" wire.
Corrected...
Higgybulin
05-22-2020, 05:57 PM
Next silly question...do you have power to any other IGN circuits? I thought I'd fried my gauges at one point only to find I'd wired the ignition with the wrong "brown" wire.
I can start the engine...how many brown wires are there?!
Specifically the one that feeds the ACC section of the fuse panel. There are two wires in the harness that could go to the ignition. I installed the wrong one. The two brown wires at the ignition switch are the BRN ACC FEED -> IGN SW (correct wire) and BRN ALTERNATOR IGN (incorrect wire). I had the wrong one hooked up.
Corrected...
Sorry -- It was the ACC feed that was messed up when I miss wired my ignition. You say you ran the gauge feed wire to the volt switch -- does it register any voltage?
Higgybulin
05-22-2020, 07:06 PM
Sorry -- It was the ACC feed that was messed up when I miss wired my ignition. You say you ran the gauge feed wire to the volt switch -- does it register any voltage?
Nope, nothing. Stuck my tester in the wire connector there and nothing. Where can I check for 12v, right at the fuse box?
Nope, nothing. Stuck my tester in the wire connector there and nothing. Where can I check for 12v, right at the fuse box?
I would check the ignition switch to be sure you have power on the ACC screw and verify the ACC FEED wire is connected to the ACC screw. There have been quite a few reports of bad ignition switches, so don't rule that out.
Higgybulin
05-22-2020, 07:54 PM
I would check the ignition switch to be sure you have power on the ACC screw and verify the ACC FEED wire is connected to the ACC screw. There have been quite a few reports of bad ignition switches, so don't rule that out.
Dave, funny you say that cause I am on my second ignition switch!!(not FF's though)
edwardb
05-22-2020, 08:06 PM
If you look at the Ron Francis harness, you'll see gauges, radio, wiper, and heater are all on the ACC portion of the panel. Meaning you engine could start and run if this whole section were out. It's powered by the BRN-ACC-FEED wire which should be on the ACC terminal on your ignition switch. Easy check would be to see if your radio, wiper, and heater wires have +12V when the key is on. If not, then that whole section is out including gauges. If they're working, I'd pull the gauge fuse and probe the fuse terminals. One of them should be +12V with the key on.
Higgybulin
05-23-2020, 06:59 AM
Specifically the one that feeds the IGN section of the fuse panel. There are two wires in the harness that could go to the ignition. I installed the wrong one. The two brown wires at the ignition switch are the BRN ACC FEET -> IGN SW (correct wire) and BRN ALTERNATOR IGN (incorrect wire). I had the wrong one hooked up.
That's a X's two for the wrong brown wire Dave!! I guess we should have known by the size of the wire we were leaving out!
Thanks again to you and Paul.
Higgy
I just had a hunch... It's an easy mistake to make, but will drive you crazy trying to figure it out.
Dave
edwardb
05-23-2020, 08:41 AM
Glad you worked it out. All electrical issues have a logical solution. It's just finding them that's the challenge. :p