Check Charging System

[mvansant]

I have an 02 ls v8. This past week my airbag light came on and my cruise control will not work. I feel that this is a clockspring problem however now two days in a row my check charging system light has come on a couple time for a very short period of time when I was driving down the road. Any idea of possible causes for charging system. Do you think the three items are related. LEt me know.

Mark

[shorod]

Welcome to the forum!

I suspect that the charging system issue is not related to the apparent clockspring problem.

The charging system message is probably due to a slipping belt or an alternator that is a bit on the weak side. Is there any common environment that seems to cause the alert? For instance, heavy rain, temperature above 90 degrees, night with the headlights on, A/C on, and at a stop with your foot on the brake pedal?

Do you have a voltmeter that you could hang on the battery or tie into the cigarette lighter to see what the charging system voltage is when the indicator comes on?

-Rod

[mvansant]

Originally Posted by shorod

Welcome to the forum!

I suspect that the charging system issue is not related to the apparent clockspring problem.

The charging system message is probably due to a slipping belt or an alternator that is a bit on the weak side. Is there any common environment that seems to cause the alert? For instance, heavy rain, temperature above 90 degrees, night with the headlights on, A/C on, and at a stop with your foot on the brake pedal?

Do you have a voltmeter that you could hang on the battery or tie into the cigarette lighter to see what the charging system voltage is when the indicator comes on?

-Rod

Rod,

No real time or reason why it comes on. It will come on sitting at idle or going down the road. It is summer so I have my a/c on all the time. The belt looks good. I went to advance auto & auto zone and both say my battery is good. They both tested my alternator and got weird volt spikes. I feel that it is my alternator but have a really hard time with that since the vehicle is only 5yrs old and 70k. Do you agree?

Mark

[shorod]

Well, the battery acts essentially as a big capacitor to filter spikes and noise once the car is started and running. However, if the spikes are large enough that their charging system tester is picking them up, they are more than a battery should be expected to filter.

Sounds like you may have a diode out in your alternator. Yeah, it would be nice to think that it would not fail so soon, but certainly there have been alternators that failed long before 5 years and 70k miles. There are a lot of electronics on your Lincoln, and a lot of demand on your alternator.

If you have access to an oscilloscope, you could scope the spikes and alternator output to determine if it is indicative of a diode/rectifier failing.

-Rod

[mvansant]

Sounds a little to complicated for me. I will jut bite my tongue and have the alternator replaced. It just kills me that within the last three months I had to replace a balljoint, clockspring and now an alternator. I had no problems for the last two years. Thanks for all your help.

Mark

[LincolnLSPaul]

I just had the same mysterious "check charging system" warnings. I thought it was due to hydraulic fluid dripping on the alternator. The leak was from the hydraulic unit that runs the cooling fan. However, the "check charging system" warnings continued after the hydraulic unit was replaced.

In desperation, on a Saturday afternoon before a trip, I replaced the battery. This stopped the warnings for about 24 hours.

I then took it to the mechanic and the readings were over 15 volts. So they replaced the alternator. Still no improvement.

After much frustration, they found the bolted wire connection to the fuse box in the trunk was loose. The wires were very hot and the fuse box was hot. Every time the wires were bumped all of the gauges and lights went crazy. We tightened the bolt and all of the problems went away.

My mysterious beeps have also stopped. You all have heard them too I see. The beeps with no messages or warnings. I have not heard one since tightening that bolt. I hope I am not overly optimistic on this issue. Wouldn't hurt to check back there.

[shorod]

Great information! Thanks for posting that.

-Rod

[Toyrolla]

Originally Posted by LincolnLSPaul

I just had the same mysterious "check charging system" warnings. I thought it was due to hydraulic fluid dripping on the alternator. The leak was from the hydraulic unit that runs the cooling fan. However, the "check charging system" warnings continued after the hydraulic unit was replaced.

In desperation, on a Saturday afternoon before a trip, I replaced the battery. This stopped the warnings for about 24 hours.

I then took it to the mechanic and the readings were over 15 volts. So they replaced the alternator. Still no improvement.

After much frustration, they found the bolted wire connection to the fuse box in the trunk was loose. The wires were very hot and the fuse box was hot. Every time the wires were bumped all of the gauges and lights went crazy. We tightened the bolt and all of the problems went away.

My mysterious beeps have also stopped. You all have heard them too I see. The beeps with no messages or warnings. I have not heard one since tightening that bolt. I hope I am not overly optimistic on this issue. Wouldn't hurt to check back there.

Yes, thanks from me as well.

This is very interesting, for I am also having this warning and it's happening very intermittently.
I plan to check the fusebox tomorrow morning (weather permitting) before replacing the alternator.

I admit that his will be my first time touching an LS (it's my father-in-law's car), so any advice and/or direction as to where to look would be greatly appreciated.
I only noticed a fusebox located in the front on the pass side, so I'm going to have to look around in the trunk.

Also, and only if it's necessary, is replacing the alternator a "science project"? Don't get me wrong, I expect a tight-fitting scenario and I just learned that it has to be accessed from under the car (ok).
But the instructions also mention that you have to remove flywheel bolts and I'm like "what?".


Thanks in advance!