battery light on/performance issues
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battery light on/performance issues
After starting my truck after work today, I noticed the battery light on. The gage was in the normal range, but about halfway between center and left. It usually runs dead center. While driving home, I noticed some performance problems driving the truck. It would not accelerate quickly and when going uphill, it would want to stall. When I got home, I read a little more than 12 volts on the battery. It is about 4 months old... I pulled codes. KOEO memory codes 14 (loss of PIP) and 22 (MAP). KOER codes 13 and 21. I am guessing these codes are a product of an electrical problems....voltage regulator or alternator??
Anyone have any insight?
MrP
Anyone have any insight?
MrP
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Joined: Mar 2002
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battery light on/performance issues
If you could pull codes, then your truck isn't that old, so the regulator is inside and is part of the alternator.
Yes, your alternator is prolly defective. When the vehicle is running the voltage at the battery terminals (as well as on the big output wire of the alternator) should be at least 13.8, maybe a little higher is it's cool outside, up to maybe 14.25 volts. A 12 volt reading indicates no battery charging is going on. Even if your battery was bad, (not likely since you say it's fairly new) the voltage at its terminals should still be close to 14 if your alternator is putting out. Check the running-charging voltage at both your alternator AND battery terminals to make sure there's no fault in the wiring. It should be the same in both places.
Most likely, that's the reason for the error codes. Even if it's not, you still need to fix the electrical system first before doiong anything else.
Yes, your alternator is prolly defective. When the vehicle is running the voltage at the battery terminals (as well as on the big output wire of the alternator) should be at least 13.8, maybe a little higher is it's cool outside, up to maybe 14.25 volts. A 12 volt reading indicates no battery charging is going on. Even if your battery was bad, (not likely since you say it's fairly new) the voltage at its terminals should still be close to 14 if your alternator is putting out. Check the running-charging voltage at both your alternator AND battery terminals to make sure there's no fault in the wiring. It should be the same in both places.
Most likely, that's the reason for the error codes. Even if it's not, you still need to fix the electrical system first before doiong anything else.
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battery light on/performance issues
Thanks for the info.
My alternator has two wiring harnesses plugged into it....not the usual terminals I am used to on older vehicles. Is the test procedure any different given these?
My alternator has two wiring harnesses plugged into it....not the usual terminals I am used to on older vehicles. Is the test procedure any different given these?
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battery light on/performance issues
Thanks for everyone's input. I had the alternator checked last night and it was bad. After I replaced it, the truck works great. By the way, it is an internal voltage regulator in the 1991.
MrP
MrP
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