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jake
09-06-2005, 03:52 PM
I seem to be only getting 10.5 or so Volts at the dash with the key on or with motor running at low idle, even though I read a strong 14 at both the alternator and battery. Don't know how long this has been going on, but the symptom that tipped me off was my perfectpass (just installed last winter) keeps resetting when I'm at low idle and doesn't even start up with the key in the on position with engine not running.

Wondering if my battery is weak and I'm just measuring it incorrectly. Anyone had this issue? Any suggestions?

Lottawatta
09-07-2005, 08:14 AM
Sounds like a grounding problem. Run a new ground wire directly from the battery and tie it into the dash ground. That should solve the problem.

Hoff1
09-07-2005, 08:52 AM
I had this exact problem on my boat. Voltage was correct at the battery, but the gage almost never read correctly. A lot of times it would be as low as 8 volts.

There were some loose wires on the back on my ignition (key) switch. I had replaced it a couple of years ago when my key broke off, and I didnít do a good job of tightening down the terminals. They got so loose, that I was having intermittent power losses while driving (seems like fuel pump, safety kill switch, or similar). Got to the point where I lost power and it would start at all. Cracked open the dash and fixed the problem in 5 minutes.

Also, believe my safety kill switch had similar symptoms when the key wasn't fitting tight and would bounce around on the chop.

whitedog
09-07-2005, 08:56 AM
Also clean the battery terminals and connections.

Leroy
09-07-2005, 09:47 AM
Maybe this will help, should be a basic circuit. If you apply your voltmeter from the solid line to the fuzzy line you should measure battery voltage (~13.8 volts DC). Trouble shooting techniques, leave one side of the voltmeter on the battery terminal and move the other lead until the terminal of the device, in this case the PerfectPass. At connections try to touch both the wire coming from the battery and the wire leaving

jake
09-07-2005, 11:11 AM
I had this exact problem on my boat. Voltage was correct at the battery, but the gage almost never read correctly. A lot of times it would be as low as 8 volts.

They got so loose, that I was having intermittent power losses while driving (seems like fuel pump, safety kill switch, or similar). Got to the point where I lost power and it would start at all. Cracked open the dash and fixed the problem in 5 minutes.

Also, believe my safety kill switch had similar symptoms when the key wasn't fitting tight and would bounce around on the chop.

Already checked the connections, everything seems good. Also, my problem has nothing to do with chop/bouncing. It's just at low idle or with the key in the on position with the engine not running, ie majority of load coming from battery. Once I'm above 1000 rpm, the problem goes away.

WTRSK1R
09-07-2005, 10:46 PM
Jake,
I have had that symptom in my 1992 ProSport since it was new. While still under warranty, the dealer replaced the safety / kill switch, but it did not really make much difference. If I am at idle, and I have the blower running, I will never have more then 10 volts at the volt meter. It will go up to about 11.5 with the blower off. You can check it at the battery at the same time, and it will easily read 13.5. Personally, I suspect the wire size used to bring the power up to the dash is too small for the amount of current being pulled by the accessories. It does not seem to impact anything in my boat other then the low reading, but I do not have Perfect Pass. If I am at normal ski speeds, the gauge usually reads just about 12 volts. I have toyed with trying to run a larger gauge from the battery to the ignition switch, but it has not been enough of an issue to bother with it. You may want to try bypassing the kill switch on a temporary basis just to see if it improves the issue.

Good Luck.

Steve