whats wrong
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whats wrong
everytime i go and put on the headlights or any electrical load, my summit water temp gauge goes up 10 degrees and my oil pressure drops 5 psi. turn them off they go back to where they were?? they share a ground from the battery
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From: Virginia
Where is your power feed coming from for the gauges? Does the water temp gauge fluctuate when you rev the engine?
I bought some Summit mechanical water temp and oil pressure guages, and was surprised how low quality they are. The water temp guage sticks occasionally, and you cannot read them at night with the illumination on. I have better luck with the cheap gauges at the parts stores.
I bought some Summit mechanical water temp and oil pressure guages, and was surprised how low quality they are. The water temp guage sticks occasionally, and you cannot read them at night with the illumination on. I have better luck with the cheap gauges at the parts stores.
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ran power from the accessory fuse (which was unused i believe) its a 15A fuse and that is powering my summit gauges. when i first hooked them up my ground wasnt the greatest and the gauges would bounce all over the place while revving like you said and do all kinds of weirdo ****. fixed the ground and thought they were okay, but now when turning on the lights exspecially when its warmed up the gauges will move from the load?? couldnt be the power feed could it. i have all 3 gauges sharing the same power feed
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From: Bristol, TN.
ran power from the accessory fuse (which was unused i believe) its a 15A fuse and that is powering my summit gauges. when i first hooked them up my ground wasnt the greatest and the gauges would bounce all over the place while revving like you said and do all kinds of weirdo ****. fixed the ground and thought they were okay, but now when turning on the lights exspecially when its warmed up the gauges will move from the load?? couldnt be the power feed could it. i have all 3 gauges sharing the same power feed
Steve
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From: Virginia
All gauges have built in power supply compensation. Ford up to about 1986 used a voltage regulator system in the dash. GM used internally compensated gauges, and Ford went to that type after 86. The normal 12v supply in a vehicle is all over the place, so you have to regulate or compensate the gauge.
I would temporarily run a power wire from the battery + to the gauges. Of course you cannot leave it this way, but it would be a interesting experiment to see if the supply does affect the gauges. If it does, I would chalk it up to cheap or faulty gauges.
I would temporarily run a power wire from the battery + to the gauges. Of course you cannot leave it this way, but it would be a interesting experiment to see if the supply does affect the gauges. If it does, I would chalk it up to cheap or faulty gauges.
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Joined: Jan 2010
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From: Bristol, TN.
All gauges have built in power supply compensation. Ford up to about 1986 used a voltage regulator system in the dash. GM used internally compensated gauges, and Ford went to that type after 86. The normal 12v supply in a vehicle is all over the place, so you have to regulate or compensate the gauge.
I would temporarily run a power wire from the battery + to the gauges. Of course you cannot leave it this way, but it would be a interesting experiment to see if the supply does affect the gauges. If it does, I would chalk it up to cheap or faulty gauges.
I would temporarily run a power wire from the battery + to the gauges. Of course you cannot leave it this way, but it would be a interesting experiment to see if the supply does affect the gauges. If it does, I would chalk it up to cheap or faulty gauges.
I understand that voltage can vary. How much can compensation can the gauges handle? What I mean here, is there has to be a maximum they can compensation for. I don't know the answer, but there must be some limit.
Steve
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Hotshot
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From: Bristol, TN.
I have been trying to research this topic. There is quite a bit of information on Internet regarding microprocessor use to increase gauge accuracy, but I can not find anything that discusses the use of microprocessors to compensate for gauge lighting.
This point remains a question for me at present,
Steve
This point remains a question for me at present,
Steve
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From: Bristol, TN.
From reading, and this is not a strong area for me, it sounds like many gauges suffer from substantial inaccuracies due to a variety of influences. As suggested earlier in this thread, manufacturers rely on advanced technologies in an attempt to correct for problems inherent in most gauges, some more successfully than others. From what I have read, I would expect more modestly priced gauges to have more problems. Others might be able to comment on their own experiences in this regard.
Steve
Steve
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Don't see here if you actually put a meter on your battery to check to see if the BATT voltage is fluxuating.....if OK, also do the alt. Write down voltage at rest. running at idle, running at 1200 RPM, running at 2k RPM. Report back.
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From: Virginia
The voltage at the battery WILL fluctuate. That's normal everyday operation for a vehicle. Nothing much running, it will be high, around 14.5v or so. As you put more loads on the system, the alternator will kick in and try to keep up, but voltage drops in the wiring still create fluctuations. And the alternator cannot have full output at idle speeds, so that also adds to the fluctuations.
The old Ford regulator worked like a flasher unit. It pulsed the voltage to the guages, and averaging it out it was about 5v. The old Ford guages worked on heat and a bi-metallic. The bi-metallic piece would bend and this made the needle read.
GM used a dual coil system in their guages. There was a coil on either side of the needle, and each coil was fed by the vehicle voltage. The difference in the coil voltages was created by the sending unit. So as the vehicle voltage varied up and down, it made no difference to the needle, since it was being pulled in two different directions by each coil. The sending unit changing the difference in the coil strengths is what made the needle move.
I am pulling this out of my memory banks from reading the manuals. Lets see if we can find a better explanation on the web somewhere.
The old Ford regulator worked like a flasher unit. It pulsed the voltage to the guages, and averaging it out it was about 5v. The old Ford guages worked on heat and a bi-metallic. The bi-metallic piece would bend and this made the needle read.
GM used a dual coil system in their guages. There was a coil on either side of the needle, and each coil was fed by the vehicle voltage. The difference in the coil voltages was created by the sending unit. So as the vehicle voltage varied up and down, it made no difference to the needle, since it was being pulled in two different directions by each coil. The sending unit changing the difference in the coil strengths is what made the needle move.
I am pulling this out of my memory banks from reading the manuals. Lets see if we can find a better explanation on the web somewhere.
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talked to summit today and they told me to put a grounding strap on the truck and take the ground for the gauges off the battery and ground it to the chassis. they seem to think as i put on a load the voltage changes at the battery as a result and screws with the gauges. sounds possible??
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From: Virginia
I would do what they say, since it's their gauges. The only problem I could see that could happen with grounding, is if the two grounds the gauges use where different. One ground is the power ground, and the other ground is the ground the sending unit is picking up from being screwed into the engine block. That might be why they are saying to put a "ground strap" on the truck. They may be saying to run a ground strap from the engine block to the cab sheetmetal.