BillZ260 Posted December 6, 2007 Share Posted December 6, 2007 Voltage reading is w/ ignition on, motor running or not is alway pegged above 18 volts. I need to check w/ a meter what the battery is putting out but in the past i know it's not much more than 14V. Any idea why this is? Painless Wiring Harness Bought John C's ROD battery which is an Eagle sealed battery, it's tiny 25 lbs. (Has held a charge sitting on the shelf for like 2 years or something, pretty impressive) I have, i think, a 60 amp GM alt, w/ the single wire hook up. Everything electrically seems to be workinig just fine. Just wondering if there is a wire I didn't hook up somewhere or something... Thanks. Quote Link to comment Share on other sites More sharing options...
Zmanco Posted December 6, 2007 Share Posted December 6, 2007 Just to be safe, you should verify the battery's voltage with a different meter. But it is VERY VERY VERY unlikely that it is much above 12v when the engine is off. So I would shift my focus to the autometer gauge itself. I'm not familiar with them so perhaps this won't help, but are there any "switches" that allow it to be used with different car voltages? For example, if it had a 6V setting, a 12V battery would peg the meter as you describe. If the voltmeter only reads high when the engine is running, I'd look at the alternator and the wiring around it. Quote Link to comment Share on other sites More sharing options...
Evan Purple240zt Posted December 6, 2007 Share Posted December 6, 2007 I have a cyberdyne gauge that reads low consistently. Also depends where your grabbing your power. Quote Link to comment Share on other sites More sharing options...
Zmanco Posted December 6, 2007 Share Posted December 6, 2007 Also depends where your grabbing your power.Connecting the voltage meter at the wrong point with the engine off would only result in a reading that was too low. Since the gauge reads too high, the focus really needs to be on the gauge itself. Quote Link to comment Share on other sites More sharing options...
Evan Purple240zt Posted December 6, 2007 Share Posted December 6, 2007 True I wasn't paying too much attention about the voltage being read with the car off. My bad! Agreed on checking voltage with a DMM with the car off as well. Good luck! Hope its nothing more serious! Evan Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted December 6, 2007 Author Share Posted December 6, 2007 Battery reads 12.4 volts car off. Got some other things going on so i can't start up the Z and check the alt. No switches that I remember on the guage, and it's hooked to the specified VOLT Guage wire from the painless harness... I'll read up on the guage liturature that came w/ them, if i can locate. Thanks for the input fella's, looks like it is the guage... Quote Link to comment Share on other sites More sharing options...
Zmanco Posted December 6, 2007 Share Posted December 6, 2007 Given your battery is fine (as expected) try measuring the voltage across the gauge. If it's 12V and the gauge is pegged, then the gauge is the problem. Another thought: does the autometer gauge have any kind of "sending unit"? In other words, is there something that should go between the gauge and the battery? Again, I'm not familiar with the their gauges so am just throwing things out there. Perhaps the autometer website has installation instructions. It's conceivable that the sending unit would drop the voltage down and without it being included in the painless harness, the meter is seeing the full battery voltage. Just a thought... Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted December 7, 2007 Author Share Posted December 7, 2007 DOH! Another good though. I'll check voltage from the wire. I know the other HOT wires have been reading 12ish volts but there coould be something cooky going on w/ the one eh? running to the garage... Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted December 7, 2007 Author Share Posted December 7, 2007 11.5 Volts at the supply wire.. Quote Link to comment Share on other sites More sharing options...
Zmanco Posted December 7, 2007 Share Posted December 7, 2007 Recap: when you are measuring 11.5 volts across the autometer gauge, it is displaying 18+ volts, correct? If that's the case, then the gauge is the problem. Quote Link to comment Share on other sites More sharing options...
Zmanco Posted December 7, 2007 Share Posted December 7, 2007 http://www.autometer.com/cat_gaugedetail.aspx?ref=search&gid=2494 I had a minute to check out the autometer website. I don't know which type of gauge you are using, but this one (which reads up to 18v) appears to be a stepper motor design, at least that's what the website says. If you haven't already done it, download the installation page for your model. An "old skool" voltage gauge will just have 2 connections for the battery and ground. This one also needs 12V switched when the ignition is on. I'm guessing that the Painless harness is set up for old skool only and that may be what is causing the gauge to read high. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted December 7, 2007 Author Share Posted December 7, 2007 Zmanco, thanks for being so helpful! The guage is MAX out at the guage, and 11.5 at the supply wire. It's this one http://www.autometer.com/cat_gaugedetail.aspx?ref=search&gid=2626 I read the instructions listed on the page and w/ in 30 seconds realized whats been going on. I'll give you a hint, the guage is trying to read 24v! The instructions point out that you only need to utilized 2 of the 3 posts on the guage. So i unhooked the sending unit wire and ta dah! 11V on the guage. I get that the 3 posts are there cause the other guages use 3 posts, but why hook them up so that this could potentially happen? WEIRD! I'm lucky it didn't burn up. Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted December 7, 2007 Author Share Posted December 7, 2007 Tech's reply on the use of 3 terminals instead of 2. Hello. The "S" terminal is simply not used for the internal meter when being used as a volt meter. It is used only when being used as a variable resistance meter. Thank you. Cory Tech/Service Quote Link to comment Share on other sites More sharing options...
Zmanco Posted December 7, 2007 Share Posted December 7, 2007 Glad you got it sorted out without any smoke! Quote Link to comment Share on other sites More sharing options...
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