Intellitec PMC Central Processing Unit

[distaff]

Question first, symptoms after:

I think my unit is having some problems and I may have to replace it. The part number is 00-00800-022 (may have been superseded by a newer part number) - I can see a few on line but they seem to specify the coach and the Intellitec product description (http://www.intellitec.com/assets/pdf...-01015-120.pdf) refers to it as "Programmable".

Anyone know if they are coach specific (i.e. the "Program" is unique to each coach installation)? I am assuming I am not the first person to have to replace one.

The symptoms are my Aquahot switch occasionally won't respond to a press - the panel of 6 switches lights up but the individual button doesn't respond. I found that I'm not getting 12v to the Aquahot board, and that I can reset the Intellitec system by cutting off 12V power (no fun going outside to cut the batteries in the rain and cold at 3 AM).

Most recently after I did this one of my other switch panels was lit up and would not go out (rear slide controls) and the bedroom lights also wouldn't respond. As noted it was 3 AM and I'd already been outside so I decided to pull the plug from the CPU - which killed all the 12v systems in the coach, and when I plugged it back in everything including the Aquahot worked.

I've also noticed that if I close the closet door over the CPU with a bit of a bang a red LED lights up on one of the relays for a moment.

These things don't seem to be user serviceable (not by me at any rate) so I may need a new one soon.

[Lee0920]

I have the same year Beaver PT, I understand these guys in Ohio can pretty much do anything with Intellitec systems.
M&M RV Electronic Repair
​
205 N. Main St.
Ohio City, Ohio 45874
mmrvelectronics@yahoo.com
419-965-3014
419-965-2662

[K7JV]

Lee is right on. Mark & Chris are amazing. They WILL help you solve your problem.

Also, unless somethings been changed on your coach, the "salesman" switch by the door should completely power down your Intellitec system so you don't have to go outside.

[distaff]

I reached out to M&M after I posted here. Mark spoke to me this afternoon but I wasn't at the coach so I'll need to try them tomorrow when I'm at the coach.

One thing he said that is a little alarming is that the PMC is programmed to the coach specifics, and the Beavers are NOT documented so the only way to make a new one is to read the code off an old one.

Good news was he didn't think it was the PCM and has some other diagnostic suggestions.

Nice suggestion on the House Power switch. I've never used it and kind of forgot it was there! That makes the reset easier.

[moisheh]

There are a few posters in the Monaco Yahoo forum that are familiar with the Multiplex system. One of them can do the programming. Try asking your question on that forum.

[nodine]

Originally Posted by distaff

I reached out to M&M after I posted here. Mark spoke to me this afternoon but I wasn't at the coach so I'll need to try them tomorrow when I'm at the coach.

One thing he said that is a little alarming is that the PMC is programmed to the coach specifics, and the Beavers are NOT documented so the only way to make a new one is to read the code off an old one.

Good news was he didn't think it was the PCM and has some other diagnostic suggestions.

Nice suggestion on the House Power switch. I've never used it and kind of forgot it was there! That makes the reset easier.

You should have M&M or Bill Groves over on Monacoers make a copy of your program just in case the unit fails and you have to purchase a new one. As mentioned, the program depends on the options installed in the coach when it was manufactured.

Bob

[distaff]

Well things got more interesting last night. The AH diesel button on the switch was illuminated and could not be turned off, no activity from the heaters in the coach, and the low battery voltage light was on the board. This morning I got out with the trusty old multimeter and found the following:

• Batteries at 13.3 V
• + to ground on the AH board (across the main leads) was 3.3 V
• + on AH board to chassis was 13.3 V
• Ground on AH board (black cable) to chassis showed good continuity.

Decided I may have some weirdness in the ground so picked up a couple of lugs and made a temporary jumper from the ground side to the chassis (used 6 gauge wire and used a bolt on the inverter mount) and got the AH back working and the Intellitec system seems happy.

Will monitor and when I get home in a few days I will trace the ground to find where it terminates and inspect it to find out what the issue is, but seems it was a bad ground somewhere in the belly of the beast.

I'll update when I have more to say. BTW got some good insights from Roger Berke and other posters over on the RV Hydronic Heating forum.

[RustyTools]

Glad you're chasing down. The Intellitec can be a mystery to work with.

Grounds are more often the issue than folks realize or remember to check - just because there's +12vdc that doesn't necessarily mean the entire circuit/loop is good.