Well, I believe you are all aware of my issues with the wheelchair light on the dash, and no throttle, shifting, etc.
Well, today I went out to look at trying some ideas on taking care of the problem of the wheelchair light causing the throttle and shifting inhibitor to kick in. At least the engine would start and run, but of course no throttle, shifting, or high idle. Now, there is nothing. No starting, no dash lights, nothing. I have full 24 volts at the batteries, the main cut off switch works, otherwise dead. It would start and week ago, now...(?)
After leaving the "on" switch on for a few minutes, the headlights came on, some of the dash gauges including the speedometer started jumping up and down, at the pattern of a turn signal. I would shut it all off and back on again, back to totally dead. I haven't done anything to it since the last time I ran the engine.
This is getting very discouraging. I think I need to hire an MCI person to make a house call and look at all this and give me a rundown on how all this works. I have been making some contact with an MCI field representative, but only a few emails. I'll have to have them come out, even if it costs a few bucks.
Grounds.
Unrelated equipment affecting each other in my experience is often due to poor/corroded grounds. It can cause bizarre behaviour.
Any ground exposed to periodic moisture is suspect even though it may appear ok. Take it apart inspect and clean. I usually follow
with something ike CorrosionX or Boeshield to try and protect it after cleaning.
-Tom P.
With a wiring diagram and voltmeter, you can trace where there should be voltage and find where it is interrupted. It will take a while but will be worth it in the end.
The problem is you have opened the ground for the lift sensor. One of the wires that you disconnected when you took out the lift was the sensor wire that needs to be going to ground. The wire will not be showing any voltage, so you can check and ground any wire that you opened that doesn't have voltage and see if that stops the problem.
You can turn the switch off with a prolink or computer with the Detroit program.
Hope that helps
Jack
If all you did was shut off the big battery switch...
What exactly is the battery voltage? On both batteries by themselves? "24 volts" isn't enough, they're dead.
Unless you isolated ALL the wiring in the battery compartment to beyond the battery switch, there are parasites that drain it down through the week...
The quick and sure way is pull the cables off the battery posts when the bus is stored, until these things get isolated.
Happy coaching!
Buswarrior
Amazing how a poor ground connection can hold on for dear life, and then once the batteries are disconnected it decides to let loose.
Quote from: Glennman on October 17, 2020, 10:04:56 PM
Well, I believe you are all aware of my issues with the wheelchair light on the dash, and no throttle, shifting, etc.
Well, today I went out to look at trying some ideas on taking care of the problem of the wheelchair light causing the throttle and shifting inhibitor to kick in. At least the engine would start and run, but of course no throttle, shifting, or high idle. Now, there is nothing. No starting, no dash lights, nothing. I have full 24 volts at the batteries, the main cut off switch works, otherwise dead. It would start and week ago, now...(?)
After leaving the "on" switch on for a few minutes, the headlights came on, some of the dash gauges including the speedometer started jumping up and down, at the pattern of a turn signal. I would shut it all off and back on again, back to totally dead. I haven't done anything to it since the last time I ran the engine.
This is getting very discouraging. I think I need to hire an MCI person to make a house call and look at all this and give me a rundown on how all this works. I have been making some contact with an MCI field representative, but only a few emails. I'll have to have them come out, even if it costs a few bucks.
Once you get the concept of breaking the system down into 2 parts the OEM reasonability and the DDEC reasonability they are not that hard to trouble shoot hang in there
Okay, so from what I'm getting here is grounds and low batteries.
The grounds are easy enough, and granted, there are some questionable looking ground connections.
But the 24 volts? 24 volts is considered dead? I have a 24 volt trickle charger, but how much is enough? 28?
My bus likes to be in the mid to high 25's when resting. Immediately after shut down it will be 26 and change and then settle at 25.8 plus or minus a tad. That is with the batteries completely isolated.
HTH
YMMV
Melbo
As melbo noted.
Battery voltage is a many paragraph explanation and cautions to measure it with some meaning.... but a 12 volt battery that has sat for a week should show at least 12.6 volts for full charge. Also, measuring the voltage after a short load is put on it, headlights, starter, also is a good indicator.
So one start attempt and batteries are found below 12.6 each, they are not up to par. And i emphasize EACH, because lots of engines are looking for the 12 volt, not the 24 volt for the computer, and it will be the computer related battery that is likely harmed.
No happy computer, no engine function
Happy coaching!
Buswarrior
Quote from: Glennman on October 18, 2020, 08:56:42 AM
Okay, so from what I'm getting here is grounds and low batteries.
The grounds are easy enough, and granted, there are some questionable looking ground connections.
But the 24 volts? 24 volts is considered dead? I have a 24 volt trickle charger, but how much is enough? 28?
If and when I get back to the shop I can send you a laminated copy of the OEM side of your bus if I have one left,the problem 98% of the time is on the OEM side so don't rush out and buy the 500 page trouble shooting manual for the DDEC it will be no help to you
Quote from: Glennman on October 18, 2020, 08:56:42 AM
Okay, so from what I'm getting here is grounds and low batteries.
The grounds are easy enough, and granted, there are some questionable looking ground connections.
But the 24 volts? 24 volts is considered dead? I have a 24 volt trickle charger, but how much is enough? 28?
Me I check the voltage at the starter and work back to the batteries it saves time
I really need a quality charger, but I put my 24 volt trickle charger on it, and it instantly says they are at 100% and 24.7 volts. The batteries are only 2 months old. If the trickle charger says 100%, them I'm sure it will not put more in. I suppose I can pull out the batteries and check them individually, put my 12 volt charger on them one at a time and see what I can get them up to.
I'll be in the market for a charger that will do both, so if anyone has any ideas on the best to get, let me know.
Here's what I use to keep the 24v batteries charged on my bus:
https://www.progressivedyn.com/specialty/pd9225-battery-charger/
If you plan on being able to charge them once the conversion is done, you'll need something better than the trickle charger. Those things are horrible, IMO. This PD charger is a smart charger and will cycle the voltage to a proper maintenance level once they are fully charged, and it brings up the voltage once a day to avoid sulfation.
I was chasing an electrical gremlin last week with my trans. The Allison keypad would just flicker an asterisk on the readout. I had the MCI guy with the computer trying to chase it and it really stumped us. It would not let the computer over-ride any of the switches. He checked the voltage on all the switches and at the fuse box. (Note: My MCI guy used to work at the MCI shop in Dallas and now has his own business. He charges less than HALF of the MCI shop rate. The key is that he knows those busses like the back of his hands including the Multiplex. He is my new BFF.)
Turns out that there was a ground bolt through the panel between were the HVAC heater core used to be and the electrical area. I had taken it out when I pulled the electronics from the heater out to get the heater core out. What I didn't realize was that on the opposite side of that panel, the trans wiring had a tiny ground wire ground connected to the same bolt, which was now hanging free. Put a new bolt through with that ground wire on it and all was well...very annoying.
I removed the batteries... one at 12.57, the other 12.7. I have a charger on one of them now, and I'll do the other one later. I'll be looking for ground issues too, but for now I am cutting down a huge Maple tree in my yard and will take most of the day to only make a dent in it. I know, I hate doing anything that is not related to the bus!!!
I like the 24 volt stationary style 24 volt charger that was recommended by richard5933. That will be my next toy.
If you get the PD charger, be sure to order one that comes with the charge wizard dongle. It allows you to check and/or change the charge mode from inside the bus.
I've got a 70-amp 12v charger for the house batteries, and the 25-amp 24v for the chassis batteries. They are plugged in pretty much all the time unless we're dry camping.
The 12v units can be found in lots of places, but the 24v one is a bit more difficult to find.
Here's where I got mine: https://www.ltdrvparts.com/PROGRESSIVE-DYNAMICS-25-AMP-24-VOLT-CONVERTER-CHARGER-PD9225-24-PD9225-24.htm
I have a 24 volt charger that I bought from NAPA. It travels in a small out of the way place in one of my bays BUT it sure has come in handy when I have needed it. My inverter / charger that I got from WRICO keeps the house batteries in good shape.
HTH
Melbo
I have one of the batteries up to 13.65 and the other is now charging. By tomorrow I should be able to put them back in and see what happens.
Quote from: richard5933 on October 18, 2020, 01:46:32 PM
If you get the PD charger, be sure to order one that comes with the charge wizard dongle. It allows you to check and/or change the charge mode from inside the bus.
I've got a 70-amp 12v charger for the house batteries, and the 25-amp 24v for the chassis batteries. They are plugged in pretty much all the time unless we're dry camping.
The 12v units can be found in lots of places, but the 24v one is a bit more difficult to find.
Here's where I got mine: https://www.ltdrvparts.com/PROGRESSIVE-DYNAMICS-25-AMP-24-VOLT-CONVERTER-CHARGER-PD9225-24-PD9225-24.htm
I didn't see the "dongle" thing, but I'll be calling their number tomorrow to inquire.
It looks like it permanently installs. Where do you have it installed?
I have it installed in my electrical bay next to my 12v charger and all the other associated stuff. I've got a remote 24v positive post installed in there so I don't need to go all the way to the battery box every time I want to add some little thing, and I think it's installed with 6 ga wire running to the battery. (Not designed for jump starting and such, just running accessories.)
Most of the units come with the dongle. They actually call it a pendent. On the 9200 series the charge wizard software is built in, and the pendent is just a way to press the button remotely. It's a small device about the size of a car remote which plugs into the charger with a cable similar to a telephone flat wire. You can make a longer one to install the pendent inside if needed. It should come with the charger, but every once it looks like a seller will try and sell them separately.
Here's photos of my electrical bay and the pendent. If you look carefully at the lower left corners of the two Progressive Dynamic chargers, you'll see the pendents stuck on with double-stick. I've since moved them upstairs for convenience.
Why the pendent? Usually when the 120v power is turned off to the chargers they start their smart charge cycle again when they are plugged in next. If I know that the batteries are fully charged, there is no need for me to let them run at the higher voltage and I just push them into maintenance mode (float charge). Otherwise, it just gives me piece of mind being able to see the blinking lights so I know what it's doing.
In your planning stage I would buy a cheap pulse 24 charger from amazon they work good keeping the batteries charged,then when you decide on the inverter and house system buy a echo type charger to keep the starting and generator battery charged
It seems like a lot of these kind of problems come from playing fast and loose with the electrical system. Now if it was the fueling system or the brakes would you be unhooking things and just walking off without ever knowing what it was to start with? No, never. Hardly ever. The reality is that doing the same on the electrical can have the same bad results. You really need to make sure you know what it is before you unhook it. Also, if the engine died would you start by pulling out the fuel tank? It really helps to look where the problem might be rather than where it isn't. More often than not it's going to be something self inflicted so start where the last work was being done. Not the opposite end of the thing.
Jim
Don't that sound familiar. I know the greatest number of my problems are self inflicted. Always "fix" something then WTF - Why'd that quit working? LOL
QuoteMore often than not it's going to be something self inflicted so start where the last work was being done.
Quote from: Jim Blackwood on October 19, 2020, 08:32:35 AM
It seems like a lot of these kind of problems come from playing fast and loose with the electrical system. Now if it was the fueling system or the brakes would you be unhooking things and just walking off without ever knowing what it was to start with? No, never. Hardly ever. The reality is that doing the same on the electrical can have the same bad results. You really need to make sure you know what it is before you unhook it. Also, if the engine died would you start by pulling out the fuel tank? It really helps to look where the problem might be rather than where it isn't. More often than not it's going to be something self inflicted so start where the last work was being done. Not the opposite end of the thing.
Jim
Yep, I understand what you are saying, except that I have not done anything to the bus wiring since the last time I started it (when I say the last time, what I mean is that last week it would start, but no working throttle, etc.). Now, after doing nothing, it won't even light up the dash, no power at all up there, no starting, nothing. That's why I started looking at the batteries (at the suggestion of those on this board). I've gone over all the grounds that I can find too.
With that being said, I now have 26.8 volts, but still no power to the dash. It's not like I need to drive it around, but I was hoping to get it to the DOT to have it licensed as a motor home before winter.