Weird electrical problem, battery not charging |
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Weird electrical problem, battery not charging |
Dtjaden |
May 14 2015, 10:57 PM
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#1
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Member Group: Members Posts: 232 Joined: 25-May 13 From: Morgan Hill, CA Member No.: 15,915 Region Association: Northern California |
A couple of weeks ago I started a drive with the regional PCA group after about 100 miles at sometimes high speeds I noticed that I was developing an engine ping under load (I have Megasquirt engine management). Looking at my gauges, while my AFR was normal to slightly rich my voltage meter was running low, about 11 volts.
At this point I turned around and managed to make it back home. The next morning my battery was dead so I used this as an excuse to install an Optima battery. After installing the new battery I noticed that the alternator light was lite when the car was NOT running and went out once the car was running. However using a multimeter the battery was not being charged. I expect that the fact that the alternator light was lite with the ignition switch off was the reason the battery drained overnight. I checked all of my fuses and all were OK. I haven't had any time in the last couple of weeks to do any further testing but since I have a spare ignition switch I plan to replace it as a matter of course. If that does not solve the no-charge situation I will need to start troubleshooting the charging circuit. I believe that the ping may have been caused by the Megasquirt management system being unhappy with the low voltage. Has anyone had a similar problem? Any advice about troubleshooting this problem? Darryl |
bandjoey |
May 14 2015, 11:05 PM
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#2
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bandjoey Group: Members Posts: 4,926 Joined: 26-September 07 From: Bedford Tx Member No.: 8,156 Region Association: Southwest Region |
Bad regulator? On the relay board. Have u checked it?
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Michael N |
May 14 2015, 11:36 PM
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#3
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Certifiable Group: Members Posts: 1,426 Joined: 6-June 04 From: San Jose, Ca Member No.: 2,164 Region Association: Northern California |
Check the voltage regulator. I knocked mine out of its socket on the relay board last year and it cause the car not to charge. I was getting ready to replace the alternator with the info from this board I saved myself a lot of extra work and money. Pull it out and reseat it in the relay board. Make sure contacts are clean.
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Tom |
May 15 2015, 03:21 AM
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#4
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Advanced Member Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None |
Darryl,
The alternator light would take considerably longer than overnight to discharge your battery. A battery with @50 A/H capacity with a load of the alternator light only ( about 0.15 amps) would take (50 divided by 0.15 = 333.33 hours) to give you the time frame. Well over a week. It sounds more likely your ignition switch is bad and causing all electrical systems to be ON even with the switch turned to OFF. So I would agree that changing out the switch would be a good place to start. Tom |
bulitt |
May 15 2015, 05:48 AM
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#5
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Achtzylinder Group: Members Posts: 4,188 Joined: 2-October 11 Member No.: 13,632 Region Association: South East States |
You may have a bad diode in your alternator.
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Dtjaden |
May 15 2015, 08:02 AM
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#6
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Member Group: Members Posts: 232 Joined: 25-May 13 From: Morgan Hill, CA Member No.: 15,915 Region Association: Northern California |
Thanks everyone. I will get to the car next week and I will post what I find.
Darryl |
Chris Pincetich |
May 15 2015, 08:37 AM
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#7
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B-) Group: Members Posts: 2,082 Joined: 3-October 05 From: Point Reyes Station, CA Member No.: 4,907 Region Association: Northern California |
There's info on using a tester wire to jumper the voltage regulator on the relay board in this thread I started.
http://www.914world.com/bbs2/index.php?sho...p;hl=alternator Good luck! (IMG:style_emoticons/default/beerchug.gif) |
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