1997 jeep cherokee 4.0l. sometimes when i start it and let it run the volts guage runs downward as if the alternator is not working and spark is coming from the battery. so i shut it down and restart it and the voltage goes back to normal as if nothing is wrong. i recently replaced the accessory belt. could it be too loose?
erratic volts
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How fast does it run down? I'm not sure a bad alternator would cause a fast voltage drop. An ammeter would be a much better tool to see if your charging/discharging the battery. You might want to pick up a cheap multimeter and check if the voltage gauge is actually reading correctly. It should be around 12.5 when sitting and 13-14+ with the engine running.
it idles normally. it seems to only do this upon first start up in the morning. i see the voltage begin to drop so i shut it down. i restart it and the voltage rises back to normal and stays there with no problem. i was thinking the belt might be loose and hence not engaging the alternator pulley properly. i dont know. it seems if this were the cause the low voltage would be more consistent. any other ideas would be helpful. i am going to check the belt tension. it adjusts manually so it might be as simple as turning a bolt.
Accckkkkkkk!!!!!!!!!!!!!!!!!!!
Electrical woes are such a pain.
R equals I over E or whatever and all that jazz.
Ohm ohm on the range......... la la la.
Anyway, read it innumerable times and found it to often be true.
"It? What is "It" you crotchety old coot?"
Patience, lads. Allow the bulbous one his pleasures. Cheap pleasures, assuredly but little harm is done.
Okay......
Harumph. Ground. "Earth" to those blarmey blokes bouncing around Britain.
Seeketh out the ground points and clean 'em up. It is a wonderful thing when a little bit of wire brushing solves an electrical problem.
At various times over the decades when various electrical problems awoke, rearing their ugly heads, undoing the nut holding the ground connector to the frame or whatever and scrubbing the pertinent metals then reattaching sometimes cured the problem.
Not always, but often enough for little OLD me to whip it out, whip it good. The wire brush!!!! A dab of goop to deter future corrosion is also a good idea but don't use goop that halts current flow!!!!!!!!
Hope this tid-bit helps since electrical problems requiring in-depth trouble shooting are a royal pain.
Also, not assuming ye are not already aware of this sage advice, just doing the just-in-case routine or offering a reminder about what ye may already know.
/left the O-scopes behind years ago.
//115 volts A/C coursing through the body hurts
///friend absorbed 600 volts and darkened 6 stories of a large building. He hurt, too, but walked away after awhile.
////zap
Electrical woes are such a pain.
R equals I over E or whatever and all that jazz.
Ohm ohm on the range......... la la la.
Anyway, read it innumerable times and found it to often be true.
"It? What is "It" you crotchety old coot?"
Patience, lads. Allow the bulbous one his pleasures. Cheap pleasures, assuredly but little harm is done.
Okay......
Harumph. Ground. "Earth" to those blarmey blokes bouncing around Britain.
Seeketh out the ground points and clean 'em up. It is a wonderful thing when a little bit of wire brushing solves an electrical problem.
At various times over the decades when various electrical problems awoke, rearing their ugly heads, undoing the nut holding the ground connector to the frame or whatever and scrubbing the pertinent metals then reattaching sometimes cured the problem.
Not always, but often enough for little OLD me to whip it out, whip it good. The wire brush!!!! A dab of goop to deter future corrosion is also a good idea but don't use goop that halts current flow!!!!!!!!
Hope this tid-bit helps since electrical problems requiring in-depth trouble shooting are a royal pain.
Also, not assuming ye are not already aware of this sage advice, just doing the just-in-case routine or offering a reminder about what ye may already know.
/left the O-scopes behind years ago.
//115 volts A/C coursing through the body hurts
///friend absorbed 600 volts and darkened 6 stories of a large building. He hurt, too, but walked away after awhile.
////zap
What spark coming from the battery ???? What's that all about ??
Superstud, eh ... let me talk to your wife a minute for a second opinion.
Superstud, eh ... let me talk to your wife a minute for a second opinion.
A sparking battery? Tighten the battery post connections.
I would say voltage regulator...of heaven forbid...you gauge could be #@$%!.
"What spark coming from the battery ???? What's that all about ??
Superstud, eh ... let me talk to your wife a minute for a second opinion."
what the #@$%!, you call me moron after this guy's szchizophrenic post. it may have been slightly unintelligible but at least he tried to offer some insight.
of course i know what part makes the spark. and if i ever catch you talking to my wife you will be tasting my pimp hand
This is nuts but wiggle the ignition switch without shutting it down next time.
Could be a 2nd contact in the "run" position is used to excite the alternator.... said contact is nuts.
Mopar likes to do it differently, with computer controls or external regulators. I remember my dakota would not "switch on" the alt for about 3 seconds after starting it. IDK if this applies to Jeeps.
Also, suprised noone has said this... get a $10 digital voltmeter and put it across the battery terminals when it's running. Should get 14 volts and change. This would indict a flaky dash gauge or wiring somewhere... not critical as the battery is still getting charged.
Could be a 2nd contact in the "run" position is used to excite the alternator.... said contact is nuts.
Mopar likes to do it differently, with computer controls or external regulators. I remember my dakota would not "switch on" the alt for about 3 seconds after starting it. IDK if this applies to Jeeps.
Also, suprised noone has said this... get a $10 digital voltmeter and put it across the battery terminals when it's running. Should get 14 volts and change. This would indict a flaky dash gauge or wiring somewhere... not critical as the battery is still getting charged.
so you think that the voltage regulator isnt polarizing the alternator rotor at start up? well its raining now, when it clears up i will try to figure out what is going on with it. it hasnt malfunctioned in 3 days now but i am pretty sure it needs to be inspected to avoid future problems. you know "an once of prevention".
PIMP HAND
PIMP HAND
Sometimes, when a vehicle (any brand can do this) is started, the ignition switch does not return 100% to the run position. It stops between the start and run positions and can cause a symptom like you describe. Next time it does it, wiggle the key to make sure it returned all the way to the run position. The ignition switch contacts can get dirty and cause it also. Good Luck.
And a large ring of keys can cause the ignition switch not to return to the run position. It can also accelerate wear on the tumblers of the lock cylinder.
Clean and tighten the battery connections [and all of your power and ground wires, while you are at it].
This will eliminate the spark from the battery.
This will eliminate the spark from the battery.
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