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Old 06-12-2004, 04:31 PM   #1
typhoon
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Calling all Wiring Guru's?? SOS!

I'm still having starting system problems, I have just finished a load of multimeter tests that indicate there is a problem, but I can't figure out what it is. Any ideas would be welcome..


My battery is dying, it reads about 10.7 volts, I have power up to my ignition switch that also reads 10.7 volts. When the purple wire is connected to my solinoid, and the ignition switch is in start, from the purple wire I read 3.4 volts. When the purple wire is off of the solenoid, and the ignition is in start, I read 10.7 volts. with the purple wire off the solenoid, and the ingnition in RUN, I'm reading 4.3 volts from the purple wire. What the?? In any case, the solinoid fails to even click. My ignition switch is brand new, and my starter and solenoid are tested used parts from the wrecker. When I test current flow from my pos Battery terminal to my block, I read 10.7 volts. From main pos power on the back of the solenoid to the block, I read 10.7 volts.

Sorry for the long post, I am beyond confused...please help!

Last edited by typhoon; 06-12-2004 at 04:33 PM. Reason: wrong word in description
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Old 06-12-2004, 05:09 PM   #2
Cat Fuzz
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Your battery is dead as a doornail. Charge it up.
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Old 06-12-2004, 06:58 PM   #3
Jeepster376
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Yup 10 volts aint gonna do nothin.
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Old 06-12-2004, 06:59 PM   #4
Springbear
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I agree... Your battery may be beyond repair... If the battery is not around 12v w/o load ya gotta start there. Then to the next step....
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Old 06-12-2004, 07:16 PM   #5
Springbear
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Maybe this will help also...

Dead battery, or bad battery terminals. Auto batteries can fail without warning, if they've been in service for two years or more or if they're defective. If you have no juice, make sure your battery terminals are tightened and clean of corrosion. If they're not, then that might be the cause. If they are snug and clean, use your voltmeter to check the battery by touching the meter's probes to the battery's plus and minus posts, scratching slightly to ensure a good connection. With the engine and ignition off, if the voltmeter reads between 10 and 12 volts, then the battery is good (9-9.5 is barely acceptable). Now that you know the battery is good, go back and measure the voltage at the terminal clamps, and then again with the positive probe touching the positive terminal clamp and the negative probe touching the bare metal or frame member that the ground wire (narrower black wire) leads to. If all of these tests measure near the same voltage, then you can rule out the terminals, too.
Alternator. A newer battery that won't keep a charge, the dimming of headlights, or stalling at stoplights are all signs of an alternator that is about to fail completely. If you suspect that your charging system is giving out, test it for certain by touching the probes of your voltmeter to the plus and minus terminal clamps when the engine is running. If it registers between 12.8 and 14.7 volts, this is usually considered within the normal range and your charging system is fine. If the voltage is too low, try the voltage at the alternator output terminals, and if it measures as low, then your alternator likely needs replacement.
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Old 06-12-2004, 07:17 PM   #6
maybizzle
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have your battery load tested. it should't ever drop below 10volts. most conventional batteries crap out once they have been discharged. buy an optima red top or any other type of dry cell battery. also check battery posts and cables. especially ground to the block and body.
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Old 06-12-2004, 09:13 PM   #7
68C15
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you have 3.4 V at purple wire when connected to sol. because the sol. is using 7.3 V. not out of line here.
when testing purple wire disconnected & in start you have 10.7 V same as batt. voltage, normal there also.
having 4.3V at purple wire with sw. in run is not right. there should be 0.0V while in run position. (ign. sw. bad)
as far as batt. showing 10.7V that is about 40% charge, not enough to start. under ideal conditions the batt voltage should not drop past 10.5V while cranking. charge batt at 10 A rate for about 2.5 hours depending on rating of batt.
most likely the reason for batt going dead is you have a (parasitic) draw in the start circuit. just not enough current flow to cause a unwanted cranking condition but enough to drain batt to point of not functioning sufficiently when needed.
it all comes down to the contacts in switch are partially touching when not wanted.
do you know how to remove lock cylinder from switch? there was a post on this recently. any further Q's feel free to ask. that's what we are here for.
Todd
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