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FPengineer · 02-01-2019, 07:11 PM

Pictured module is casually laid across the tops of the chassis and coach batteries. Module, along with the coaches wiring harness and other electrical modules, were designed and provided by Electronic Design & Assembly of Bend, Oregon. A call to the only phone number found for company is not in service. The module contains six fuse holders and one relay, all set in a potting compound. Company’s part number is 2504150 dated 11/26/1997. Module is not shown on the few schematics I have for the coach.
a) does anyone recognize and know the function of the module? and
b) is there any remnants or reincarnations of this company left if replacement parts are ever required? Thanks a million!
v/r,

W Taylor Hudson, Jr.
Black Creek, Florida (Jacksonville)
Clemson University class of ‘80
1998 Safari Serengeti (40’ DP)
(1997) Caterpillar 3126, 7.2L, 300 HP, 800 ft-lbs @ 1440RPM,
first generation HEUI direct injection
Allison 3060 six speed “World” transmission
Magnum chassis (Goodrich Velvet Ride rubber block torsion suspension)

MrWzrd · 02-05-2019, 11:58 AM

I feel your pain (hate that phrase)

I had similar "black boxes" in my 14 year old coach. Took to tracing the circuits to figure out what they were.

In your case... is is possible it is something as simple as the 12 distribution for the coach? Is there a fuse panel elsewhere? If you pull the fuses does anything stop working?
Or possibly something that was put together for a trailer connection? (I had one that was a horrible nightmare and took me most of a day to remove it and get the original circuits running)
It might be a battery management system. Are the wires connected to each individual battery?

Sorry I can't do more than throw speculation. If you have any more info or a photo showing where the harness heads off to, it might help in figuring out what it is.
Good Luck

C&SL · 02-05-2019, 04:41 PM

FPengineer
I do not know what it does, but the last post might help a little or may not.

https://www.rv.net/forum/index.cfm/f...d/27914950.cfm

C&SL
005 Sig

SmokyPond · 02-05-2019, 05:03 PM

Does your coach have anti-lock brakes?

Although the model and year of my coach is different from yours, my exhaust brake relay, Bosch anti-lock brake relays and fuses are all on single board. While not in the battery bay, the board is located in the next bay back, above my inverter/charger.

FPengineer · 02-06-2019, 09:07 AM

Wizard, Smokey Pond, and C&SL,
Thanks for the response and suggestions!

I have a 12 volt fuse block in the front most left compartment with three busses (switched chassis, non switched chassis, & coach).

I do not know if the unit has anti-lock brakes. Brakes are Bendix Hydro Boost (powered primarily by the power steering pump and incorporating a backup 12 volt pump. Reminds me of what Chevrolet diesel powered 3/4 and 1 ton pickups of that era had. Are four wheel disk. I guess one might call that hydraulic over hydraulic?). Parking brake is a cable operated drum brake on the drive shaft reminiscent of some ‘60s Chrysler products with automatic transmissions. Good suggestion to pull fuses and see what quits working.

Unit has a PacBrake which sounds from the owners manual it is controlled somewhat by the transmission ECM, have not tried it yet.

Engine will not turn over since I removed all batteries to refurbish the rusted battery rack. Ignition functions will not turn off with key once the key has been turned to on (ignition power solinoid “latches” on), transmission controller remains dark, I am thinking an open return (ground) in the related circuits. Photographed the terminations before removing the batteries and am sure all wires and cables are landed correctly. Engine will turn over from from the rear bay auxiliary start button. Following several threads, believe it is a loose connection in the battery compartment vicinity due to all the horrible crimp type butt splices in the area. Need to remove the cheesy black smurf tubing and do some tracing. (Personally think any manufacturer that uses butt splices should be hung in the town square puntucially at ten o’clock the following Saturday morning).

Will correctly install the mystery unit in a dry location verses leaving it atop the six batteries waiting for it to snuggle down through the smurf tubing and cause some metal case to battery terminal contact excitement.
v/r,

W Taylor Hudson, Jr.
Black Creek, Florida (Jacksonville)
Clemson University class of ‘80
1998 Safari Serengeti (40’ DP)
(1997) Caterpillar 3126, 7.2L, 300 HP, 800 ft-lbs @ 1440RPM,
first generation HEUI direct injection
Allison 3060 six speed “World” transmission
Magnum chassis (Goodrich Velvet Ride rubber block torsion suspension)

SmokyPond · 02-06-2019, 04:00 PM

Well FPengineer, your coach is a lot closer to mine than I would have thought. My coach also has the HydroBoost braking system, as well as a Pac Brake.

Note that the ABS Pump relay on my anti-lock board has the "Bosch" name across the top of it.

BTW, the ABS pump is located under the coach about a third of the way back from the front of the coach, slightly towards the street-side from center. Just follow the brake lines from the HydroBoost unit. You should find it easily if you have it. Also, look for the wheel speed sensors.