Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Willy White on February 22, 2017, 07:49:38 pm
Title: Javelina A/C Logic Controller
Post by: Willy White on February 22, 2017, 07:49:38 pm
Is there an source for replacing this AC Controller? I will be calling Foretravel in the morning to if they can help. Steve
Title: Re: Javelina A/C Logic Controller
Post by: DavidS on February 22, 2017, 08:49:46 pm
If I could find mine I could remove it.. looked under the console under the dash and couldnt find it.. unless I missed it.
Title: Re: Javelina A/C Logic Controller
Post by: Roger & Susan in Home2 on February 22, 2017, 08:59:30 pm
Steve, it this under the floor of the dash storage compartment? I quit using mine and went to a seelevel tank monitor and different backup cameras. If it is in there you are welcome to it. I am in the Tucson area now.
Title: Re: Javelina A/C Logic Controller
Post by: Willy White on February 22, 2017, 09:24:19 pm
Yes this controller is behind the center console mounted above the vacuum solenoid and not the old tank monitor. This controller operates the dash air system by SGM Co. Inc. Steve
Title: Re: Javelina A/C Logic Controller
Post by: Roger & Susan in Home2 on February 22, 2017, 09:41:32 pm
I had part of my dash AC/heat vent controls fail. FT did a hard wire work around. Not sure what they did but the defrost didn't work. It does now.
Title: Re: Javelina A/C Logic Controller
Post by: Willy White on February 22, 2017, 09:41:59 pm
you can see the controller mounted in the center on the blower cabinet.
Title: Re: Javelina A/C Logic Controller
Post by: Roger & Susan in Home2 on February 22, 2017, 09:46:28 pm
I guess you have it torn apart. While you are in there add a switch to the dash blower used when the AH is on. Makes a big difference in comfort.
Aqua Hot Dash Blower Fan Override (http://www.foreforums.com/index.php?topic=23713.msg185057#msg185057)
Title: Re: Javelina A/C Logic Controller
Post by: krush on February 22, 2017, 09:50:10 pm
If you cant find a replacement, call these guys, they probably can fix it for fair price Generator & RV Controls Repair and Replacements, Engine Monitoring, Idle... (http://www.flightsystems.com/)
Title: Re: Javelina A/C Logic Controller
Post by: Willy White on February 22, 2017, 10:09:31 pm
Roger, I move the rig 40ft to finish overhauling the big awning and this happen. I just rebuilt the entire dash air AC system last summer and work great, just can't believe I'm working on it again. Yes while I'm in the dash I will clean up the old wiring and add the switch you mention and overhaul the blower motors. Been working on this rig for over a year restoring it and she won't turn me loose! Steve
Title: Re: Javelina A/C Logic Controller
Post by: Willy White on February 24, 2017, 04:19:28 pm
According to Foretravel this Dash Air "AC Logic Controller" was only used for the 2001 model year. I contacted SGM who was the supplier through Javelina and they where no help, they couldn't even supply me a schematic of this circuit board. Shot a picture of it to Flight Systems to see if it could be repair and the answer was-SORRY. Anyway I'm searching the wrecking yards before I start to the long process in designing a new relay panel. I attach a Dash Air wiring diagram for those 2001 owners that may need it in the future that Foretravel sent me. Steve
Title: Re: Javelina A/C Logic Controller
Post by: Willy White on March 19, 2017, 08:59:07 pm
After exhausting all resources in locating new or used I was force to try to rebuild the relay board myself. It isn't pretty but it fully functional. The micro relay on the board that failed supplies power to the dash fan motor during aqua hot heating cycle. Power the feeds this circuit comes from a coach side 30amp circuit breaker through a 20amp rating micro relay (the one that burned) through another 40amp relay to the dash fan motor. There was a loose push-on (brown wire) the 40amp aqua-hot relay that even discolor the terminal that I believe over amp the micro relay until it fried. Anyway I added a 15amp fuse to the ground side for a added protection. I took the time to service the fan motors since they were filthy beyond belief, it really blows hard with 47 degrees supply air now. I almost forgot, I added a spare switch that I had on the dash to disconnect the 40amp aqua hot relay so the dash fan won't function during heating cycle at Roger's suggestion. Steve
Title: Re: Javelina A/C Logic Controller
Post by: Jan & Richard on March 19, 2017, 10:08:05 pm
It may not be pretty but it looks like a beautiful work-around. Well done. Thanks for sharing.
Title: Re: Javelina A/C Logic Controller
Post by: Roger & Susan in Home2 on March 19, 2017, 11:46:32 pm
Nice job Steve. Let us know what you think about the dash blower override when the AH heat is on. We think it makes the LR temp distribution and comfort better and quieter.
Title: Re: Javelina A/C Logic Controller
Post by: Woody & Sitka on April 03, 2020, 07:57:36 pm
Old thread, I know, but those with 2001 coaches (apparently the only year FT used this POS logic box) might be interested in an update with similar failures.
I've experienced intermittent dash blower operations with the Aquahot living room demanding heat. Found that jiggling the wire harness on the left side of the first pic would get it to run for an hour or so and then it would quit again. This box is mounted to the dash HVAC box, behind the panel in the center dash lower compartment. Decided yesterday to pull the box and check out the guts. Found a similar failure as Willy White but not as severe. On a whim, I tried to contact Javelina but every avenue ended with disconnected phones, etc. So there's another news tidbit.
I could have mucked around with trying to repair the failed solder joints and a broken trace, next to the solder connection marked with the red arrow in one of the pix, but found a TV repairman in town, who fixed it overnight for $62. Works great again and it'll be nice having that dash blower working when the temps get down to single digits here, or to keep the windshield defrosted overnight before departure. I've installed the switch Roger recommended and it's nice to be able to quiet the blowers when needed.
Repair guy said that the solder that Javelina used was low temp, and the circuit traces were inadequate to handle the blower amps passing through those P600 diodes, and the resulting heat caused the cold joints and other heat related failures of the relays that Willy saw. In Nov, I inquired at MOT, who contacted Foretravel engineering for a work around for this logic box, and there's nothing out there or in the works. We're on our own. No idea what to replace this logic unit with if the thing finally craters. If anyone has any ideas, please chime in. Woody.
Title: Re: Javelina A/C Logic Controller
Post by: Chuck Pearson on April 04, 2020, 11:40:03 am
I'd think an Arduino might well handle these functions. If you could give me an idea of just how many parameters there are I'll look into it.
Title: Re: Javelina A/C Logic Controller
Post by: Woody & Sitka on April 04, 2020, 06:34:43 pm
Chuck, Willy posted the schematic in the thread above, but unfortunately none could be found for the internal workings of the Javelina unit. If of any use, the burnt circuit traces in Willy's repair post could provide a clue I guess. The controller is just relays and diodes, which control all the vacuum dashpots and fan relays. The biggest draw is the dash blower fans, necessitating the 2 P600 diodes. Man I hate chasing electrons, and these units are destined to fail with no replacement currently available, so if this is in your area of expertise, those of us with 2001 coaches could make a side business for you some day!! Woody.
I'd think an Arduino might well handle these functions. If you could give me an idea of just how many parameters there are I'll look into it.
Title: Re: Javelina A/C Logic Controller
Post by: Chuck Pearson on April 05, 2020, 09:32:35 am
Okay, 15 relays to control dash air. Yes it would be possible to replace with a logic device but the programming would be onerous for such a limited use device. Looking at the photos, as you know, the power diodes are overheating. No wonder there, those are 6A diodes.
I recommend you remove those diodes, toss em in the can and use this, or something similar.
Its rated at 25 amps, so should take care of the overheating issue. They should be mounted off the board, preferably free standing so they can dissipate some heat without frying the board. There are, of course many other diodes that will work as well probably Amazon sells some. Other than that the board looks pretty stout, and this will probably be your best route to repair.
Title: Re: Javelina A/C Logic Controller
Post by: Dave & Diane on October 05, 2020, 03:48:23 pm
Old thread, I know, but those with 2001 coaches (apparently the only year FT used this POS logic box) might be interested in an update with similar failures.
I've experienced intermittent dash blower operations with the Aquahot living room demanding heat. Found that jiggling the wire harness on the left side of the first pic would get it to run for an hour or so and then it would quit again. This box is mounted to the dash HVAC box, behind the panel in the center dash lower compartment. Decided yesterday to pull the box and check out the guts. Found a similar failure as Willy White but not as severe. On a whim, I tried to contact Javelina but every avenue ended with disconnected phones, etc. So there's another news tidbit.
I could have mucked around with trying to repair the failed solder joints and a broken trace, next to the solder connection marked with the red arrow in one of the pix, but found a TV repairman in town, who fixed it overnight for $62. Works great again and it'll be nice having that dash blower working when the temps get down to single digits here, or to keep the windshield defrosted overnight before departure. I've installed the switch Roger recommended and it's nice to be able to quiet the blowers when needed.
Repair guy said that the solder that Javelina used was low temp, and the circuit traces were inadequate to handle the blower amps passing through those P600 diodes, and the resulting heat caused the cold joints and other heat related failures of the relays that Willy saw. In Nov, I inquired at MOT, who contacted Foretravel engineering for a work around for this logic box, and there's nothing out there or in the works. We're on our own. No idea what to replace this logic unit with if the thing finally craters. If anyone has any ideas, please chime in. Woody.
So this issue only applies to owners of 2001 FT's? For me, a non Aqua Hot u270, what exactly does this box do. I have this area open right now as I have removed the Javelina Audit 5T7 CPU box. I already had a new side and back camera system and tank level system installed by PO so it's taking up space. My dash air is not blowing cold anymore (it was last year) so I'm curious if there is anything related here. Doesn't seem like it would but you never know. So from what I can gather is that for me, on a basic u270, I have to turn on the blowers thru the selector fan switch in the dash area, where coaches with the AH can also control those independently when the 12v automotive side is not engaged? Any comments would be appreciated.
Title: Re: Javelina A/C Logic Controller
Post by: Woody & Sitka on October 05, 2020, 11:21:41 pm
Dave, I can't say whether your U270 has this controller or not, but I'm guessing it does. On mine it controls every single part of my dash hvac, and incorporates the A/H coil and fan controls as well. My dash A/C quit working this spring, right after I had the board repaired with new diodes only to make the defrost blowers come on with the A/H. Coincidence maybe, but I've checked all the components and have narrowed it down to the Javelina unit, or the Ford dials on the dash.
You'll find the controller (if it's there) screwed to the back side of the metal hvac cabinet, once the center console storage compartment is disassembled....see Willy's picture in Reply#5. It's not visible or accessible any other way. It should have a paper nomenclature label on it.
If your coach does not have this controller, I'd be extremely interested to see how it's configured and wired, since I'm ready to delete Javelina from my coach and my memory. So please document your findings for us poor '01 schmucks.
I'm actually researching replacing the entire dash HVAC with a Vintage Air or ComfortAir unit, or similar. Might be the best alternative in the long run....will keep y'all posted. Woody.