M2 Freightliner Ambulance Conversion Project. 2007 Crew Cab

[Ozrockrat]

Getting rid of the V-MUX:
1- no reasonable way to diagnose or repair.
2- Spares are very expensive.
3- Not able to reprogram functions without spending upwards of $6000 on software.
4- control for things like scene lights only function from the cab.
5- main isolator needs to be on to have control.
6- when isolator is on the screens light up the night too much for camping.

The main saving grace for the V-MUX is that it’s in place and working.

1- With the Raspberry Pi and all it’s components I can carry a full spares kit for around $200.
2- all associated sensors are cheap and easily available. (May not be rugged enough but time will tell)
3- ability to combine controls into a single button. I.e night viewing mode sets all lights to red and reduces intensity or camping mode enables right scene lights, rear scene lights, left scene light but disables door switches. Then when finished camping put it in drive mode(or truck is put into gear) turns off all scene and under body lighting and re-enables door switches.
4- Ability to include additional functions such as tank levels, motion detection, security cameras, messaging and maybe even monitoring key parameters on the trucks J1939 bus.
5- because it is a fun project I can do with my grand daughter (after we build a retro gaming machine)

A couple of key project guidelines for me:
1- all switchable functions must have a manual override. (Isolated manual switches can also control relays)
2- no/minimal bespoke hardware except for breakout/IO control boards.
3- reuse existing code where possible (I have a bad habit of thinking I can do everything better and reinventing the wheel)
4- keep it fun.
5- make it reproduce-able potentially commercially available.


My main focus initially is replacing the functions controlled by the V-MUX so basically all the lighting. Especially for the camping kit. Pump and scene lights currently need the V-MUX powered up. To turn on the pump (I repurposed the suction pump the same as every other ambo I have done) I need to:
1- turn on the isolated at drivers door.
2- go to the control panel in the module.
3- turn on pump.
4- go and use the pump (drivers side at the moment is the only outlet)
5- being lazy and if I remember I the turn off the isolator otherwise I have to either unplug the pump or switch the pump off in the module.

The RPi solution would have me set the truck up in camp mode and use a momentary switch plus flow switches to control how long it stays on when switched. For example when the shower is in use keep the pump on for 1 minute after flow stops (to allow for navy showers). But with the sink it only needs to stay on for 30?? seconds. But if there is water flow from the pump and neither of the flow switches for the shower or sink are active turn the pump off and set an alert for a leak.

There is a lot more potentially including controlling the engine preheat while the vehicle is stored. The good part being it can all be done incrementally. (agile development = always releasing a functioning product).

 

[rlrenz]

And as the old saying goes: "You can earn as you learn". The system can grow and become more sophisticated as you become more familiar with it.

Definitely good reasons to remove the V-MUX system. As you probably found out, a new control screen module sells for about $900, and maybe a little less for used nodes. The system was completely set up for emergency vehicles, and trying to convince it that the vehicle is no longer an ambulance is an uphill struggle. The bits and pieces should be salable as a bonus.

You would have had the same challenge with a Horton Intelliplex system, except it's set up specifically as an ambulance system, and re-programming it would be an "interesting" challenge.

And you also just reaffirmed my appreciation for my Medic Master's relay/diode/switch logic. More wires to fiddle with, but they're all labeled every foot with the circuit # and identification. A new relay is about $4, so I can handle repair without breaking the bank.

My own system is configured a little differently - I have a separate 12 volt panel just for the RV portion that's fed by deep cycle batteries, so the water pump, RV lighting, entertainment, whatever - are all isolated from the vehicle starting batteries. The deep cycle batteries have a pair of Xantrex Echo Charge units to top them off from the main batteries when the main batteries are being charged, and a separate Iota 45 amp charger for when the vehicle is plugged in to shore power. Since the vehicle will also be used as a USCG Auxiliary communications facility, the deep cycle batteries will additionally power a 50 amp radio bus.

 

[Ozrockrat]

I am envious of your switch and relay controls.

My first instinct was to just replace the module V-MUX with switches and relays for exactly the reason you mentioned. But then the old problem kicked in. Why just do something when you can over do it.

But I will surely live up to my “donor twice then do it right mantra”

 

[Ozrockrat]

My money is on your granddaughter.

Yeah I figure this one is going to cost me a lot of Cold Stone trips.

 

[Ozrockrat]

One of the other reasons for changing is to help tame this bed of snakes.

 

[Ozrockrat]

Another interesting fact. The scene lights on this truck are halogen but they only run at 5 volts. Just tried replacing them with LED RV lights and got a resounding failure. So then I tried the warning lights but the wiring pulses to give the flashing on these Now another 1/2 hour job will turn into an all day mess. I might just go with a simple switch (only draw 1/2 amp) and worry about the actual scene light wiring/controls later.

Do it twice then do it right.

 

[Ozrockrat]

Damm 1/4 wider and they would of covered the holes.

Also they are deeper than a normal light and will not fit in the 2” cavity. Luckily I have a bunch of wasted space behind some of my lights.

And before anyone asks.

LED RV Exterior Flood Porch... https://www.amazon.com/dp/B07F1J192N?ref=yo_pop_ma_swf

 

[rlrenz]

I did my warning and scene lights the "easy" way....

I had left my warning lights as-is, except I replaced the clear lenses GEV had installed (in place of the original red & blue) with amber lenses at $35 each. Fine, but they were too visible when off to suit me. After about a year of looking, plus the help of an ambulance electrician friend, I managed to assemble a set of Whelen 900 amber LEDs with clear lenses for the sides, and Tecniq 9x7 K90 amber with clear lens for the rear.

I was able to track down Whelen LED scene lights for the sides, and Tecniq 9x7 K90 scene lights for the rear.

So, the "easy" solution. Far from the cheapest, but plenty of light. Plus, I have a box full of blue, red, amber, and clear lenses left over for further entertainment... if I can ever figure out what to do with them. Wind chimes (for people like me who hate chimes dinging) maybe?

Plus, I can change my standard Whelen ambulance halogen flasher for a newer LED flasher. Not a biggie, but why not?

 

[rlrenz]

Another interesting fact. The scene lights on this truck are halogen but they only run at 5 volts. Just tried replacing them with LED RV lights and got a resounding failure. So then I tried the warning lights but the wiring pulses to give the flashing on these Now another 1/2 hour job will turn into an all day mess. I might just go with a simple switch (only draw 1/2 amp) and worry about the actual scene light wiring/controls later.

Do it twice then do it right.

5 volts for scene lights sounds fishy. Every scene light I've run into runs on 12 volts. I wonder if somehow your system doesn't think they're warning lights, and it's trying to run them on low intensity? Or - is there a chance that they are miss-wired and are connected to a warning light string?

Is there a chance that somewhere along the way, someone installed scene in place of warning and vice--versa? On the vehicle sides, warning lights are the outer two (farthest forward and farthest rearward). The scene lights are the lights closer to the vehicle center.

 

[Ozrockrat]

Is there a chance that somewhere along the way, someone installed scene in place of warning and vice--versa? On the vehicle sides, warning lights are the outer two (farthest forward and farthest rearward). The scene lights are the lights closer to the vehicle center.

I plugged them into the warning lights as well. Warning lights get a pulsed 12v and these lights worked on them (disco theme thought).

The scene lights run through the V-MUX so I am thinking they must do the magic in there. I threw my hands up in discuss, uttered a few Aussie adjectives that can also be verbs and ran another set of cables for now.

I also put the scene lights to the ends. This was both to actually get them to fit (have enough space in behind) and also to spread the light out a bit.

For now I am just going to put them on the same relay (timer) as the checkout lights. I replaced my inside lights with LEDs so it shouldn’t be too much of a load and the switch is just inside either door.

Now I’m just waiting for nightfall so I can check them out.

 

[rlrenz]

And still more reasons to remove the V-MUX

I replaced all my interior Whelen halogen ceiling lights with Tecniq ambulance ceiling lights. No regrets at all. More light, and no heat!

 

[Ozrockrat]

Ok finally done (for now).

Compared to this (only 1 scene light connected as I have the other removed to run the shower plumbing)

Did a check on the current draw. Turning on the existing lights involves turning on the module power. This creates an 11 amp load (not sure what is being powered except the bloody lights in the doors). The single scene light draws about 4amps. So turning on the single scene light created a draw of 15 amps.

Since the new LEDs do not need the module powered up they draw just over 2 amps (2 RV area lights and 3 internal LED ceiling lights )

I’m going to class this one as a win for now. When I do the new control system I will have them split off so I can individually control them and maybe even put them on a dimmer depending on how they handle PWM.

 

[patoz]

Good job on the install Bevan, and they look like they'll get the job done!

I'm using the Whelen 900 series High Intensity 90° Gradient Opti-Scene lights, and considering they are 6,500 lumens each, I'm considering doing the same thing and putting mine on dimmers also. Since I'm also planning on using my rig for emergency communications, etc. in disaster situations like hurricanes, I need to be able to light up a good perimeter around it, but for camping these things will fry your eyeballs.

 

[Ozrockrat]

I decided to steer clear of the Whelen 900 series. All of my existing 900 series LEDs are cracking at the screw mounts from branch whacks. And I haven’t even started taking this truck in the rough parts yet.

Add that to the high $$$$ and very high lumen count I figured I would give the $39 reseed ones a go.

I am also considering replacing my 900 series warning lights with something recessed. Probably build them myself as amber and red scene lights that can double as warning lights if needed. I do have a set of amber/red warning lights on the back I want to retire as high level brake/tail/turn signals.

 

[patoz]

Whelen is definitely proud of their stuff! Just about everything I've rounded up for mine is used but in good condition, with the exception of a few pieces, but it's taken me about four years to find it all at good prices.

What about the light bars, do you have any plans for them?