Hi everyone,

FTP here (first time poster). We bought a 2000 dodge caravan, 3.3L v6 (I think) new from the dealer. Now has 176K miles, with almost no problems, until 3-4 days ago. Suddenly having trouble keeping the battery charged, and the charge light comes on almost immediately after starting. Cleaned the terminals, and replaced battery (it was due). Still having issue. Using my multimeter, I tested across the battery terminals, while running. I only get about 12 volts, which I presume is battery voltage, meaning I'm getting nothing from the alternator.

My question is how can I determine if this is an alternator issue, or regulator issue (integral to the PCM, if I understand correctly).

Any help or suggestions? Thanks in advance!

 

Engine running, you should have battery voltage at the large terminal and at the Dark Green / Orange wire. If the brushes are garbage, you will have no power at the Dark Green wire. If you have power at the Dark Green wire, you sould be able to momentarily tap it to ground to full field the alterator. Most likely, bad brushes. Test with a test lamp and not a meter.

 

OMG, I'd forgotten just how badly I hate wiring diagrams! That simple diagram makes it look so - so- well so simple! Where do you recommend that I check this dark green wire that you refer to? The only places that I can see that it is even remotely accessible is at the alternator (really stretching the notion of accessible), and at the PCM. Accessing it there pretty much requires removal of the battery, then rotating the Power Distribution Center out of the way in order to access the two PCM wiring connectors. How am I supposed to do either of those things with the engine running? Is there somewhere else that this dark green wire is accessible that I'm just not seeing??

HELP!! (please)

 

After lots of testing, probing, more than a little cursing, etc. I yanked the alternator out (that was a first class pain in the a$$.) Took it in to that store that sells Advanced Auto parts (yep, shameless plug) and had them test it. First time the test completed, the machine asked the tech to verify tha the cables were hooked up. Ran the test again, with the exact same results. Absolutely NO outout voltage from the alternator. Bought a new rebuilt one, and a new idler and tensioner pulley just for good measure. put things back together, and no more battery light!

 

I replaced 2 alternators on my 2000 GC. First one was replace with the high output one. (The one it came with) The second with the lower output one. (lifetime warranty, second one was free) Advanced auto pulled a fast one on me and gave me the low output one, I was at work and had to install it to get home. Its a lot easy to install (smaller) and should not hurt anything. Been a year and all is well.