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 #380113  by IMSpecialX2
 July 31st, 2019, 12:52 pm
Hi, My Battery keep draining in My 2003 M Special while I'm driving, I Charge it up to full, but, as soon as I start and drive the car for few Mins the Battery light comes on and the car goes into limp (won't shift past the 2nd Gear) and the dash lights goes dim.

This issue started when the weather got Hot and I started using the AC, the first time it did that, it was Just the battery light that came one, I thought it was something minor the car was trying to adjust to, since I never used the AC Much unless it was Extremely Unbearably Scorching Hot! Normally I just rolled down the windows. The next time it also light My AirBag Light (for whatever reason...)

But, on this fàteful day, I started the car drive it out about 1.5miles, Pulled over, cut the engine off while I was waiting to pick someone up, I went to start back the car, Dead battery, good thing My instinct told Me to carry My jump box. I started the car again, Dash lights dim, Car running like it's not Happy at all almost like it wants to shut down. Tried to make it down the street, Won't shift past 2nd gear again, So I had to drive back home. Plugged it again, next day, Battery fully charged, Started car fine, Battery Voltage bouncing all over the Place, between 10.5v-12+v, back and forth like that. But, once I try to drive it, the voltage drops straight down.

My Trusty handy battery tester tells Me My Battery is good, It holds charge. I even took Her to AdvanceAuto and they Tested My Battery and Alternator and Told Me My Battery is good and My Alternator is Bad.. I know for sure alternator is not charging the battery, But, that doesn't Mean My Alternator is Bad either, My concern is the the Voltage Regulator, I know there is a well known issue with Voltage Regulator Circuit going bad, Since they are inside the PCM, it's had to get to or test (At least by a Rookie like Me).

So I want to know, what can I do at this point? I don't wanna start changing parts. Is there a way to actually test alternator? And an Easy way to test the Voltage Regulator Circuit? To know what the actual problem is...

I do have a Chrysler external voltage regulator that I plan on finding a Trustworthy Technician to Install if that's the case... I bought 2 of them sometime ago when My 02 M and '00 Intrepid was giving Me those battery drain issue, Albeit, Neither of them ever Flashed Battery Light.. But, Luckily all I did was Change the Battery and never had the issue again. I thought of Just changing the Battery On this one, But the rate the Battery is draining makes Me feel like that won't solve it.
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 #380116  by Sneke_Eyez
 July 31st, 2019, 2:02 pm
If you take your alternator out, you can have it tested at one of the Auto Parts Stores - they usually have a tester.

Taking the alternator out isn't too hard, it is just 2 bolts and disconnecting the power (and removing the crossmember).
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 #380123  by FIREM
 July 31st, 2019, 4:30 pm
There is no known issue with the BCM Voltage regulater on LH vehicles. What were the actual test results from your battery testing? How many CCA ? Why do you not believe the test result that the alternator is bad as you stated? Other than the occasional SSR Fuse or Fusible link issue, easily tested, kind of sounds like you need to replace the alternator
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 #380124  by LUNAT1C
 July 31st, 2019, 5:19 pm
The symptoms you're describing are indicative of a bad alternator. I would take it out of the car and have it checked by the parts store.
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 #380135  by M-Pressive
 July 31st, 2019, 8:22 pm
Sounds like an alternator to me.
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 #380157  by IMSpecialX2
 August 2nd, 2019, 5:22 am
Ok Thanks Everyone, I will Remove the Alternator and Have it Tested. Will Come back with The Results.
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 #380158  by IMSpecialX2
 August 2nd, 2019, 5:48 am
FIREM wrote: July 31st, 2019, 4:30 pm There is no known issue with the BCM Voltage regulater on LH vehicles.
No? Well, Why does 3 out of 5 LH Cars that I've had have this battery/Charging Issues then?
FIREM wrote: July 31st, 2019, 4:30 pm What were the actual test results from your battery testing? How many CCA ? Other than the occasional SSR Fuse or Fusible link issue, easily tested, kind of sounds like you need to replace the alternator
My Battery CCA is At/Around 670-700CCA, Battery CCA Capacity is 750, The Tester Lights Up Green for Pass Every time.
I've read alot about this SSR Fuse situation, I Checked Mine, It's not Blown.. But, May I ask what is it? What does it do? And What does the SSR Actually stand for?
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 #380159  by FIREM
 August 2nd, 2019, 6:22 am
IMSpecialX2 wrote: August 2nd, 2019, 5:48 am
FIREM wrote: July 31st, 2019, 4:30 pm There is no known issue with the BCM Voltage regulater on LH vehicles.
No? Well, Why does 3 out of 5 LH Cars that I've had have this battery/Charging Issues then?
In the 17 years this forum has existed there has not been a reported BCM caused charging issue.
You appear to have some unique issues.
FIREM wrote: July 31st, 2019, 4:30 pm What were the actual test results from your battery testing? How many CCA ? Other than the occasional SSR Fuse or Fusible link issue, easily tested, kind of sounds like you need to replace the alternator
IMSpecialX2 wrote: August 2nd, 2019, 5:48 amMy Battery CCA is At/Around 670-700CCA, Battery CCA Capacity is 750, The Tester Lights Up Green for Pass Every time.
I've read alot about this SSR Fuse situation, I Checked Mine, It's not Blown.. But, May I ask what is it? What does it do? And What does the SSR Actually stand for?
Battery results look good,
SSR fuse controls the "Field" signal from the BCM to the alternator. Field signal signal regulates alternator output.
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 #380163  by adu1982
 August 2nd, 2019, 12:10 pm
4 lh cars, burnt 2 pcms myself so replaced them with used units. Not one bad bcm , so that would be about 7. Some here have had 7 lh cars in their fleet with no bcm issue. Bad alternators , while the oems are robust, I have had 2 bad

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