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I do well enough with wrenching, but when it comes to electrical I'm less handy. Is the BCM broken up into segments, such as one for turn signals, one for power door locks, one for windows, etc.? If so, can a single segment be swapped out? Being on limited income, a $125 part (new BCM) is pretty steep for me. I have an 05 T&C, with a wheelchair lift, and otherwise everything is in tip-top condition.
 

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Welcome,

Some of us around here know what it is like have limited disposable income.

I do not have an answer for you, but someone should happen along and offer some guidance soon.

I for one will keep an eye on this to learn the answer. Please do return and let us know what/if you find something out.
I love a happy ending and it is what keep me warm on these cool early spring nights...

Cheers! Again, welcome to the forum!
 

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Thank you Gator, it's great to know folks are so responsive here. Also appreciate the tip in your signature; being a network engineer, all such useful virtual clues are stored for as long as my personal hard drive lasts. :cool:
 

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What's the problem? BCM may or may not be the root cause...

In any case, the "generic" test/cure is to pull the IOD fuse and re-insert it 5 minutes later to see if any of the symptoms change.
 

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What's the problem? BCM may or may not be the root cause...

In any case, the "generic" test/cure is to pull the IOD fuse and re-insert it 5 minutes later to see if any of the symptoms change.
The power door locks have stopped functioning. They also no longer engage when I start driving. Pressing the lock button makes the horn toot, so the fob is working.
 

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The power door locks have stopped functioning. They also no longer engage when I start driving. Pressing the lock button makes the horn toot, so the fob is working.
Try pulling IOD fuse, if it gets your locks back for a short while, the problem is electrical (ground, supply, or AC leak)
If your battery is getting up in age, get it load tested. Check and clean battery terminals. Cleaning and inspecting grounds is a good idea also.
If none of the above gets rid of it (or you have an oscilloscope), test the alternator (if one of the diodes is shot it will still produce enough power but will leak AC and 'throw off' electronics, starting with BCM)
 

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If none of the above gets rid of it (or you have an oscilloscope), test the alternator (if one of the diodes is shot it will still produce enough power but will leak AC and 'throw off' electronics, starting with BCM)
Greetings, diodes are also very easy to test for failures as they only pass current in one direction. Passing current both ways, naughty diode! Also, check your relays. I don’t know if I helped you at all (probably not) but let us know what you come up with.
 

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Greetings, diodes are also very easy to test for failures as they only pass current in one direction. Passing current both ways, naughty diode! Also, check your relays. I don’t know if I helped you at all (probably not) but let us know what you come up with.
Is the alternator/diode test done in situ? I would guess it requires engine revs and/or battery power to produce a waveform...?
 

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While individual diodes are easy to test, the stator on the alt is 'wye' config and there are 6 diodes in the circuit...

The simple (you might even say 'redneck') way to test the blown diode theory is to charge up the battery and disconnect the field coil on the alt - it will set a fault code but if BCM continues to operate without issues vs. loosing locks as soon as you re-connect the field you'll have a good idea that alt has something to do with it (though it's by no means a conclusive test). Just don't drive too far, it will drain the battery...
 

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While individual diodes are easy to test, the stator on the alt is 'wye' config and there are 6 diodes in the circuit...

The simple (you might even say 'redneck') way to test the blown diode theory is to charge up the battery and disconnect the field coil on the alt - it will set a fault code but if BCM continues to operate without issues vs. loosing locks as soon as you re-connect the field you'll have a good idea that alt has something to do with it (though it's by no means a conclusive test). Just don't drive too far, it will drain the battery...
How about the charge tester cart I have seen at Advanced auto parts? Will that actually tell the operator anything like ac leak? Or is it just a consumer impression generating multimeter.

I remember atoman or timmyb (some, one, of those smart, respected folks... jeepman, Levy, JoelB. I forget.) saying something about using a multimeter somehow to check for AC leak. (it was the first I had heard of AC leak or AC leak causing havoc with onboard electronics, but I can believe it)
Was it as simple as setting to to ac volts and reading at the battery or perhaps it was at the alternator output stud?

(now I trust the "technicians" at advanced auto parts about as much as I trust their "lifetime" parts... ) That being said, I will gladly buy consumable stuff that comes in a sealed container from them and take advantage of their complimentary tool rental and OBD scanner.:headbange I do spend money there, just not so much on hard parts when I want (or need) reliability.:biggrin:
 

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IDK what tester Advance has, but I wouldn't trust the few workers I dealt with over there to put a battery in my car...

DMM can be used as a poor man's aid, but you'd not get anything conclusive from it. Probes should be placed on lead battery posts, not clamps.
 
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