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Time to replace alternator or wiring problem?

I was driving on the highway and the battery light came on. Then I was sitting in traffic and the Jeep just stalled. I restarted and could only keep running if I gave it gas. The check engine light came on. Went back on highway and got home.

The MIL is 12 (battery disconnect) & 25 (idle air control motor circuit). The battery still has almost 13 volts.

Id this a wire or short or is the alternator going/gone?

Reply to
Mel P.
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Clean the idle air passage. It's gummed up.

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You don't need to take the TB off, just clean the top and bottom of the valve with a toothbrush and some carb cleaner. Then go around the bore. Next with the engine running, spray cleaner into the passage just above the valve. Try to keep the engine running. If things are real bad you might have to take the idle motor and valve assembly off and clean it on the bench. NOTE: Never run the engine with the idle air motor dissembled, the idle air motor/solenoid will be damaged.

Reply to
DougW

oh.. and as for the battery, check and clean the terminals. Usually, but not always, when they get loose all sorts of codes can be set. Code 12 just means the battery was disconnected within

50 startups.
Reply to
DougW

I agree ... man knows what he's talking about ... same problem, same solution .. easy job

Reply to
Mindy

Another odd problem can be with the inline fuse wire. Mine started throwing battery/alternator codes and it turned out that the fuse wire was corroded and broken where it was crimped to the alternator output wire. The problem was erratic and getting worse but it took forever to locate the problem.

Reply to
Will Honea

evbeergoggles.com

Reply to
csdude

Doug,

I understand code 12 and have gotten it before on several occasions for different reasons. But my battery light came on. Should I be concerned about my alternator? Maybe the voltage regulator?

thanks again,

Reply to
Mel P.

Could be the battery. If it was the alternator there would be other codes thrown. That and I've got a 93 ZJ with the original alternator so they do last quite a long time.

I've slept since yesterday, what is the year/model of your jeep?

These come in handy.

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URL, but there are several three LED versions of the same thingthat help diagnose low/high charge and low/high capacity.

Reply to
DougW

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