Chinook RV

Essentially, you need to figure out where does the voltage drop happened. It is somewhere between the charger and the battery, and there is not a lot of components between them, so should not be that bad to figure out.... Good luck.

Ok- BobW9 attached is a doc with my measurements per your instructions. In addition, I also did what caconcourse suggested, which was remove LVDin connection then measure voltage at Vout. Results were- LVDin 12.47, LVDout 9.10! Big diff, altho I have no idea what that means. Shore power was on when I did these measurements.
One other thing- I decided to check the connections from shore power to the back of the PD4645. The wire nut on one leg of the connection was melted and there was heavy corrosion on the wires- see pics. It was getting close to the end of the day and I had been messing with this issue since this am, so I did a quick clean of the wires and put a new wire nut on them. I was hoping that this was the source of my problem. But when I reconnectd to shore power still no charge voltage going to the batts!
Tomorrow I will check and clean all the connections to the PD from shore power and see if that makes any difference.

Okay. First of all, congratulations on finding that bad wire-nut connection. Obviously it had gotten so bad that the resistance was causing a lot of heat. Good thing it had so far just melted the plastic cap, not started a fire. Well, done.

Conclusion: From your measurements it kind of looks to me like you only have current going one direction, from batteries to distribution panel. To wit:

1) voltage seen at panel is 13.74 when batteries are being charged and are at 14.3. This seems reasonably, a 3.9% voltage drop across the fairly long AWG 8 wire run used between panal and batteries (at least I think it was an 8 on mine).

2) voltage seen at panel is 11.85 when just on batteries at 12.45. Again, seems reasonable with about the same drop of 4.2%. Don't get stuck on small differences, as measuring can be tricky and vary by how good you connect each time and how good the meter is. We're in the same ball park both times.

3) Voltage seen at panels is 13.7 when converter/charger running - this is tough to decide what it means. 13.6 is Normal voltage for the converter when it sees the batteries are full. But according to the Charge Wizard docs which I just checked, 13.6 is also what it will read if not connected to batteries at all. And we also see the batteries reading 12.49. This is within margin of error for measuring that might very well match the batteries by themselves in (2) above at 12.45. Meaning both charger and batteries seem to be at, or close, to the voltages they'd have if they aren't even connected.

How about taking the LVD out of the circuit completely and then testing for shore power charging, all measurements again?

Remove the VIN positive power wire(s), then VOUT positive power wire(s), and connect them together tightly using a bolt. Make sure you take a picture or mark each wire somehow before, so you can put each wire back on the correct side after the tests!

** Be very careful when doing this, as the LVD can be fried if you disconnect its ground connection from the battery while it has a power connection to the battery (I know, mine did) ** Leave that ground connected!

Oh, and just those positive wires are all we're interested in. The white ground wires connecting to the LVD are for it to work (and some other Chinook wiring), not part of the battery to distribution panel circuit (the panel's ground goes from the panel down to the frame via the big wire conduit bundle behind the panel).

My comment is that if you want to bypass the LVD, another method is to connect the V-in with the V-out with a piece of wire, loop around the posts, and tighten up the nut on the posts. Less likely to mess up. I assume the LVD is the stock Chinook LVD, not other brands.

Update- Bypassing the LVD by connecting the Vin to the Vout wires resulted in no change. Still no charge going to batts.
Redid all the connections in the back of the PD4645 after cleaning the wires. Still no change.
Checked the ground connections on the chassis nothing loose. I was going to clean and redo each one but the connections are rust welded. I'd have to cut the wire to each ground, remove the old connector from the chassis frame, install a new connector and then reconnect each of the grounds. Not ready to do that unless I'm sure that's the root of my issue.
I have contacted Progressive Dynamics to see if they have any thoughts.
I need a drink!

Sounds like something went wrong from the PD4645 to the LVD, don't you agree? There are only two wires there. The red wire from the DC panel to LVD, I think it is 8 AWG, and it is bolted down to the BATT + post. And the black wire going from the DC panel on the BATT - post to the chassis. The chassis then carry the the ground near the battery tray, a short thick black cable, maybe a 4 AWG to the battery terminal. The ground wire on the LVD is white, and you also need to make sure it is making a good contact with the chassis.

To trouble shoot, you need to find out where the voltage drop is. With the voltmeter probe on the BATT+, touch each of the negative points along to route to the battery negative and the LVD ground. It will be easier to do the positive route (one path), by having the voltmeter probe on the BATT - on the DC panel, then touch the following points and see where you see the voltage drop: BATT+, LVD-out, LVD-in, and battery positive terminal. I think you already did the latter, but I do not know if you have the voltmeter probe on the same spot (that is, on the DC panel BATT -). If you did, then it probably is some nicks or cut on the 8 AWG red wire between the LVD-out and the BATT+.

Have you have any rodent problem in the rig? You may want to get a 15 ft long 8 AWG wire and connect the LVD-out to the BATT+ on the DC panel and see if the problem disappear. That way, you can bypass the potential defective wiring between the LVD and the DC panel.

It is not that bad to find out the issue, and I think you already did most of the work.

Thanks for the reply and suggestions Chin_k. and yes I agree with you. I will try tracking the voltage drop tomorrow hopefully. I haven't mentioned this but I am also in the midst of rebuilding the entry door to our Chinook. I wasn't expecting to have to jump back and forth between the two projects. But it is what it is!
I was thinking along the same lines as you about running a jumper from the batt + on the PD 4645 to the LVD Vout. Just wasn't sure if that was a good idea or if I even had a heavy and long enough wire to make the jumper out of. I have plenty of #12AWG. Do you think that would be ok just for a quick test?

BTW we have had to deal with mice in the rig but nothing recent.

Rodent may not be able to get to where the 8 AWG wire is, except for the space behind the brown box, so it may not be the reason. I am just throwing it out there, so don't read too much into it right now.

If your coach battery is pretty full, I don't think it will suck 45 Amp thru the wire... measure it with an ammeter for a few seconds if you want to be sure... I think a 12 AWG should be fine if you just do a quick test and don't care if you need to throw it away because the conductor melted . Just put a 15A fuse on it (or just use one of the DC panel output with 15 or 20A fuse on it, and go from there instead directly from the converter or BATT + if you want to be careful.

OK, so #12 is rated for about 9 or 10 Amp. You can use jumper cable that you use for auto, or triple or 4X multiple wires together if you want to be safe. If you just want to use a single #12, you will see a slight higher voltage drop than the original #8 wire, but it should not be too bad. Guess what? Just use multiple #12, and put a fuse on it. I hate it when someone go after me for making less than 100% safe suggestion to people, just in case someone who have less experience than you got into trouble.

One quick question for review. Are all your 12V appliances working when not plugged into shore power? For example, when the engine is running. If so, there is probably not an issue with the wire between the PD4645 and the LVD, because it is bi-directional, and used to provide battery power to the appliances. Also, all your measurements at both ends of that wire indicated a 3 or 4% drop as I recall, which was reasonable for the wire length and size.

I am beginning to suspect the PD4645 charger may be broken. It is outputting as though there are no batteries connected, so maybe it has a problem in the battery voltage sense circuit. I suspect the output amps in that condition are minimal, so the battery wouldn't see a charge even if the output voltage is 13+.

Also, Progressive Dynamics has included a Lithium mode for the new models PD4645LIV?) , so If I were replacing the PD4645, I would get that new model to allow switching to Lithium batteries in the future.