Makalu

So I just did as you recommended. I ran an inline 20amp fuse and connected 12vdc to the ECM wire. I just used the fuse as my "switch" if you will. Then I just touched a wire from a 12vdc power source to the starter solenoid you circled in red and it fired right up. NO "Eng Comm Failure" on the dash and it didn't die at all in the 15min or so I idled it and revved it up slightly. So this clearly seems to indicate some type of issue with the board, specifically that K1 relay. One question I have is; I have no other fuse lights lit up in the rear run box when it's running now (I honestly don't recall if they are when the motor was running when the PCB board WAS working). Is that indicative of anything? Would I be able to drive the coach like this, temporarily of course? I greatly appreciate your insight, Frank. You are a legend.

I will report back tomorrow, but I suppose it's possible the ignition signal is somehow at fault. And thanks so much for the insight. I hope I can get this sorted.

This is what I was wondering about. But upon investigating the 3 position rocker switch that you can select "Front, off, Rear" with, I noticed it killing power to every board in the back run box and initiating a "Eng Comm Failure" dash warning. Even the guages up front were cycling from zero to full and back repeatedly until I turned the ignition off again. All I was doing with the switch was making sure it was set right on the PCB board. Then after replacing it I still had the issue. Then pressing slightly upon the board itself would sporadically kill power to the whole rear run box, literally every fuse light flickering off and on. Needless to say, it has me puzzled.

Would it make sense to you that I have this issue with the motor just shutting off on me if that intellitec board is going bad? Then displaying an "Eng Comm Failure" on my dash when it does? Even had a friend come out and plug in his Cummins Insite to the coach and he saw a code for an "Intermittent Ignition Power Loss" or something worded similar. It has made the coach undriveable as you can imagine.

Great, I will try this tomorrow. Thanks Frank. You are a wealth of information! Curious where you came across the schematics for a 2008 Navigator? I'd love to have them.

Thanks a bunch. If I'm understanding correctly I need to still have the board to bypass it? Unfortunately I already shipped the board off to get diagnosed/repaired.

I believe I've got a bad PCB board in my rear run box that is going bad. It is the 73-00825 board that has the 3 position rocker switch that allows someone to start the coach from the rear or select "front" to continue to use the key ignition. Then a momentary on/off switch to actually start the motor. I had my motor die on me 3 different times and got an "Eng Comm Failure" dash warning as a result. I replaced the switches on the board as I read a bad one can cause issue. The new switch came and I ruled it out as the problem. But upon pressing slightly on the board, or moving the switch at all, I get intermittent power loss throughout the rest of the pcb boards in my rear run box and all the fuse lights flicker on and off. Then the motor recycles it's start procedure/lifter pump etc. So after talking with M&M RV Electronics, I send out the board for testing/repair. They should receive it Tuesday, though likely can't get to working on it for maybe 10 business days (bummer). Is there anyway I can bypass this board to start or move the coach while the board is being repaired?

I had a blowout in the front right steer tire on my 2008 Holiday Rambler Navigator. A small bit of tire fragment must have tore a couple wires out that interact with my Lippert steps. Since the tire blow-out I've had to manually attached the grey wire to the bottom bolt in the picture of the wheel well. This closes the steps. If the wire is not attached it leaves the stairs out. My step switch just inside the door of the coach doesn't work any longer. I believe the previous owner replaced the steps at some point because the sticker on the underside of the assembly shows a date of manufacture in 2018. The grey wire was an extended piece of wire off another white wire. I *think* the two loose wires in the pic were both attached to the bottom of the two bolts in the picture. The door sensor no longer works to operate the stairs, nor the switch. The motor sounds fine in operation and retracts and extends fully otherwise. I'm scratching my head. The steps and switch control worked flawlessly before the tire blowout. Please see the attached pictures for an idea of what's I'm dealing with.

Just an update for the Kongsberg sensor. It appears to be working in the short bit of driving I've done with it. Yay! Second to that, and almost more importantly, where I'm currently staying is a bit north of Houston. Well, I come to find out that Konsgberg has a manufacturing plant 4 miles away in Willis, TX. I stopped by and explained to a nice gentleman with Kongsberg the difficulty all of us RV'ers are having sourcing a replacement sensor. They don't deal direct with consumers but he had good ol Texan friendliness and felt bad for my situation. He gave me his cell phone number as he was headed to lunch. He gave me some very valuable insight though. Essentially saying the OEM sensor is programmed for a dual analog output signal. I asked if there was any possible way I could get this same sensor made for me or if there was an updated part #. His engineering team said it was an old unit and no longer manufactured and are programmed to specific requirements and ultimately sounded a bit hesitant due to liability. But that another dual analog output signal sensor would likely work. I then sent him a picture of the Polaris Slingshot (Polaris is a large purchaser of theirs) sensor I purchased and explained I had to have it mounted exactly 180 degrees opposite the factory sensor (facing downward on the Teleflex pedal). He was at first concerned it may cause issues but then checking with the engineering team again, he said the serial number off the Polaris sensor was also a dual analog output and that if when the pedal in resting position, and the coach idles as normal (I confirmed with Cummins Insite software 0% throttle at idle), and it revs up to 100% then I should be good to go. It does. They also sell a lot to Cat and Club Car but not sure if this sensor is utilized on anything they make for those companies. I haven't bothered to look.

That looks like it. Just ordered it. Thanks much!

Now I'm in need of this sensor. Goes into the transparent bottom of my fuel/water separator. As you can see the yellow wire broke free from the sensor. I am going to attempt to solder it but ultimately I'd like a whole new sensor. Wondering if it's why I'm getting an "Engine Comm Failure" message on my Medallion display and sometimes unable to start the coach (cranks but won't start on occasion). As seen in this thread over on irv2.com https://www.irv2.com/forums/f123/engine-comm-failure-72170.html

Yes this fix posted is for a Teleflex adjustable pedal with the Kongsberg sensor on it. It has 6 wires running into the plug. The part number for the Kongsberg sensor is 6543212.

Ok so I've figured it out. The Polaris Slingshot pedal mounts the sensor in the downward direction. As you see in the picture. By taking that sensor and mounting it in the downward direction on the Teleflex pedals on my Navigator it works! And it makes sense that the mounting direction needs to change because this is the direction the Polaris pedal mounts. It's possible changing the rotation of the magnet 180 degrees would accomplish this as well. I haven't tried to remove it. But purchasing the Sensor off a Polaris Slingshot and installing it pointing down appears to work.

Gary, I edited my post to reflect that it does appear to rotate clockwise with both pedals (the oem Teleflex AND the Polaris Slingshot). But what I'm finding is that the magnet orientation inside the sensor must be different so I can only get increased throttle by keeping the sensor unmounted (not bolted in) and manually rotating it. I need to figure out if I can somehow re-orientate the magnet to the correct idle position or if that's even possible. Or if that's even the issue. To answer your question, I paid about $125 on ebay for the whole pedal assembly WITH the Kongsberg Sensor 6543212. If I can figure this out and it's a viable solution it could very well save many members a large amount of headache and cash.

Ok to follow up on my post above this. I got my sensor installed from a Polaris Slingshot pedal assembly. The new sensor only works by rotating it the opposite way on the magnet, strangely. I'm a bit baffled by this. Still trying to wrap my head around it.