Trans comm err eng comm err No Vansco Data

[Fezziwig]

Hello to all Alpiners! Welcome to my first ever post. I have been lurking on this board for almost 3 years now and thanks to the enormous amount of information posted by you all for so many years, I have been fortunate enough to have solved all my issues and answered all my questions without having to bother anyone. Until now! Despite plowing through what I think have been all the relevant posts I have been stumped for weeks by a stubborn “trans comm err eng comm err” code on the Actia gauges and “No Vansco Data” on the Silverleaf screen as well as the resulting fail to start condition. I’m hoping someone can help me.

This is going to be a long post as I want to add as much information as possible about what I’ve done/learned so far to save time, so I’m going to try to break it up into sections to hopefully make things clearer.

THE QUESTIONS
What does the 12 volt relay in the battery compartment fuse block power?

Is there another way to program a spare Vansco other than the description in the Alpine Tech library?

Is there a way to determine which Vansco software is on my units, ver. 3 or 4?

What does the white wire labeled 154 at the Vansco J1 plug (lower right side) do? What pin on the Vansco, if any, does it connect to?

What is the function of the twisted green/orange wires at the various plugs?

BACKGROUND
I’ve had my coach for almost 4 years adding 24,000 miles (Total 71,000 miles) There’s been no previous electrical or Vansco issues. I had the Actia gauges sent out a year ago to successfully repair the LCD screen. I upgraded the batteries to LifePo and added solar panels about a year ago with no issues since. The last work I did a few weeks ago was to try to replace the backup lights with new LEDs. Wife put the rig in reverse and the lights didn’t work because the cheap imported Amazon lights were not the right replacement. Shut it down and the problem began the next morning when we tried to start it.

THE PROBLEM
Rig would not crank, “trans comm err” and “eng comm err” appeared on the gauge. Silverleaf screen added “No Vansco Data”. Gauge needles would sweep back and forth endlessly but otherwise not work except for the fuel gauge. Transmission shift pad lit up and responded to input. Last week I broke down and had a mobile mechanic come out, who couldn’t fix the problem but did show me how to jump start the engine. I can now move about but with no gauges. I can only start by getting out and jumping the second solenoid with a wire to the battery.

FUSE BLOCK IN BATTERY BAY
Previous posts have indicated bad fuses in this block could be a problem. The 10 amp fuse for the Ign-Alt/Air Tank was blown, replaced it and it made no change. All fuses tested good as did the 12 volt Omron micro relay. HOWEVER, when I checked connections on the block for this relay, I got the following strange results. When the ignition key is turned on, the connector for pin 86, (which is supposed to energize the relay) only shows 3.3 volts. That is not enough to energize the relay and in fact the relay does not audibly close when the key is turned. Just as well for two reasons; first the measured voltage at the connector for pin 30 is only 4.6 volts. I would assume that a 12 volt relay in a 12 volt system should be supplying 12 volts. Am I wrong? Secondly, the connector for pin 87, which is supposed to receive the 12 volts from pin 30 when the relay is closed, is actually going to ground! So I assume the wire leading from the connector for pin 87 has somehow shorted to ground. Can anyone tell me where that wire is supposed to go? What is it powering? Any ideas about why such low voltages at 30 and 86?

VANSCO
Issue 1. The Vansco units power up and it appears that all the lights light up correctly at the key off and key on positions front and rear, EXCEPT no flashing NET light. From what I’ve read in the “VMMS2820 Diagnostics 8.26.15” document in the tech library and previous posts, that might mean they are not communicating. The confirming test is supposed to be to step on the brakes which should light up input 24 in front (it does) and output 12 in rear (it doesn’t).

Issue 2. I tested the resistance between pins 32 and 33 of the J1 connector on the front Vansco and got a reading of 73,900 well above the range of 35,600 and 38,000 as described in the same document above. The readings in the rear and spare Vansco were within spec. These are the pins that the twisted yellow and green comm wires connect to.

Issue 3. I tested the resistance within the green and yellow comm wires themselves and got a reading of 0 ohms rather than the 60 I should be seeing.

Issue 4. When disconnecting the lower right side connector on the front Vansco on my second try to program the spare Vansco, I noticed a small white wire labeled 154 was disconnected from the plug, just the wire with no metal connector attached. I did not see any metal connector within the molded plug that the wire might attach to, nor did I notice any small connector laying on the ground nearby. I have no idea when this occurred. Did not notice it the first time but could have easily missed it given the number of wires clustered there. Could this be the reason the Vansco will not program? Could that little metal connector in the molded plug have been pulled out through the front?

Issue 5. I tried to program the Vansco twice per the directions in the tech library with no luck. Net light did not light up, power light continuously blinked.

I disconnected the coach from all power for 30 minutes (twice), that did not help. I pulled all the connectors from the Vanscos, ABS ECU, transmission ECU and engine ECU. All were clean, bright and undamaged.

I know there’s a lot here but thought best to get all the info out at once. I’m hoping somebody can make sense of this and point me in the right direction. One of the big questions for me is which of the things I’ve found are the cause(s) and which are simply the results. Or are they all unrelated problems? I would appreciate any and all responses, inputs, ideas or musings. Finally, the coach is n storage 200 mile away, so I probably will not be able to get back to it for a few days at least.

Thanks to all in advance!

Oscar and Lynda

[Fezziwig]

Ok, looks like I screwed up already; my signature is not appearing. While i fix that my coach is a 2007 Alpine 36 FDTS!

[Steve and Linda's APEX]

A couple of general questions:
Have you checked your chassis battery voltage?
Your Vansco is powered by your chassis batteries.
Why are you replacing your Vansco?

[Fezziwig]

Hi, thanks for your response. Yes, I forgot to mention the batteries are topped up (over 13 volts) and plugged into charger. Starts right up when I jump the solenoid.

I don't necessarily want to replace my Vansco. I was trying to swap out the front Vansco to eliminate that as a source of the problem.

[Terry W]

FWIW I think I'd swap the Vanscos front to rear and see what that does, no change or problem follows, see if it tells you anything.

The front Vansco is a pita to remove by yourself but the rear is pretty simple. I'd do this before I threw a new unprogrammed unit into the mix.

I have programmed a unit using the instructions and it worked like a champ !

[c_oneil]

I could offer some information off of '05 wiring drawings that is still valid for your '06.


"What does the 12 volt relay in the battery compartment fuse block power?"
I can only tell you what the relay contacts are connected to. The relay contacts from the BACK side of the fuse block and left to right are connected as follows:
top LH = Trans ECU connector P125, pin #31 (32 pin Gray connector)
top middle = not used
top RH = ground
bottom LH = ABS ECU connector P127, pin #12 (15 pin gray connector)
bottom RH = Trans ECU connector P125, pin #27 (32 pin Gray connector) this is also wire marked 154 that you say is disconnected at the front Vansco.


"Is there another way to program a spare Vansco?"
Not without special proprietary software or special wiring harness. Is your spare Vansco that you are trying to program already programmed or is it new un-programmed?


"What does the white wire labeled 154 at the Vansco J1 plug (lower right side) do?"
I don't see any wire marked 154 at the front Vansco J1 plug or close by. The only place I see it is at the ABS ECU connector and the relay on the fuse panel.


"What is the function of the twisted green/orange wires at the various plugs?"
The twisted yellow/green wires are the twisted pair CAN-low and CAN-high data communication wires. The network traffic is confirmed by the flickering green LEDs on the Vanscos. Since your's don't flicker that is not right.


When you got 0 ohms checking the green/yellow pair something is wrong there and needs to be sorted out. Endless gauge sweeping, "trans comm err", "engine comm err" these are all devices that communicate on the CAN bus and yours appears to be not working. It may not have anything to do with the Vanscos.

[Fezziwig]

Originally Posted by Terry W

FWIW I think I'd swap the Vanscos front to rear and see what that does, no change or problem follows, see if it tells you anything.

The front Vansco is a pita to remove by yourself but the rear is pretty simple. I'd do this before I threw a new unprogrammed unit into the mix.

I have programmed a unit using the instructions and it worked like a champ !

Thanks for you're response Terry. I tried to program the spare to avoid the pita of swapping front to back but will probably have to try that the next time I'm at the coach.

[Fezziwig]

Originally Posted by c_oneil

I could offer some information off of '05 wiring drawings that is still valid for your '06.


"What does the 12 volt relay in the battery compartment fuse block power?"
I can only tell you what the relay contacts are connected to. The relay contacts from the BACK side of the fuse block and left to right are connected as follows:
top LH = Trans ECU connector P125, pin #31 (32 pin Gray connector)
top middle = not used
top RH = ground
bottom LH = ABS ECU connector P127, pin #12 (15 pin gray connector)
bottom RH = Trans ECU connector P125, pin #27 (32 pin Gray connector) this is also wire marked 154 that you say is disconnected at the front Vansco.


"Is there another way to program a spare Vansco?"
Not without special proprietary software or special wiring harness. Is your spare Vansco that you are trying to program already programmed or is it new un-programmed?


"What does the white wire labeled 154 at the Vansco J1 plug (lower right side) do?"
I don't see any wire marked 154 at the front Vansco J1 plug or close by. The only place I see it is at the ABS ECU connector and the relay on the fuse panel.


"What is the function of the twisted green/orange wires at the various plugs?"
The twisted yellow/green wires are the twisted pair CAN-low and CAN-high data communication wires. The network traffic is confirmed by the flickering green LEDs on the Vanscos. Since your's don't flicker that is not right.


When you got 0 ohms checking the green/yellow pair something is wrong there and needs to be sorted out. Endless gauge sweeping, "trans comm err", "engine comm err" these are all devices that communicate on the CAN bus and yours appears to be not working. It may not have anything to do with the Vanscos.

Thanks for all the info here, much appreciated.

I'm not sure we're talking about the same relay though. Here is a picture (from the tech library) of the one I'm referring to. It's at the bottom right labeled Omron



My understanding is that this is a simple electric witch. On the back Pin 85 is supposed to be connected to ground and when Pin 86 is connected to 12 volt
that energizes the relay causing Pin 30 (12 volt supply) to connect to Pin 87 and powering whatever that wire is connected to. Is that not how this relay is set up to function? I do not remember what the wires in back of the fuse block are now.

Regarding the Vansco, I bought this off Ebay in July 2020 used. I was told it was unprogrammed but don't know how to verify other than try to program it.

As to wire 154, I will need to get back to the coach and see what possible brain fart I may have had to either mis identify or misremember the wire id.

My question as to the twisted wires is to the green/ORANGE pair, not to the green/YELLOW pair with the shield wire. Of course I don't have a picture of that, but it seems to run to every ECU connector that the green/yellow does.

And finally, the 0 Ohms reading at the wires is a problem of course, but so is the 73,900 reading at the Vansco pins 32-33. I read somewhere that such reading meant that the CAN buss within the Vansco was "shot" with no further elaboration or advice as to what could be done about it. I cant help but think this is all related to the same source problem.

Thanks again for all this info, gives me a lot to think about!

[c_oneil]

It is a rainy day here and I love a good mystery so why not:
The relay in your picture is the same as I am talking about. Just a micro automotive relay. It is rated for 12V dc but it would work for lower voltages too and I don't know what the trans ECU and ABS ECU are designed for so maybe the lower voltages you are seeing are correct. If you wanted to know what it is controlling you might need to research the pin out assignments for the ABS and ECU.


My bad on the orange/green twisted pair. I just assumed one man's orange wire was the same as a yellow wire. The orange/green is a separate J1708 data bus that shows up in at least the trans and engine control connectors. I think the ABS might use it too. The yellow/green/shield cable is the newer J1939 protocol. I think the Vanscos are only connected to the yellow/green/shield J1939 cable.


One of my Vanscos is a bit out of the 35.6K to 38k ohms spec you quote but works fine. Granted your is almost double but??


If your spare VANSCO was previously programmed say for use in an MCI transit bus there is no way for you to re-program it without a special setup.


0 ohms across the high and low sides (green/yellow) is definitely bad. It would indicate a direct short of green to yellow or direct shorts of both to ground. I don't know what your typical failure mode of a CAN bus client is but it could also be an internal short in any one of the clients not just the Vanscos. You would need to unplug all the clients and reconnect them one at a time to check. Good idea to disconnect all power to make sure the CAN bus is not powered while you are testing.


Do you have some way to check for stored Cummins error codes? Any check engine or ABS warning lights or are they all dead with the rest of the dash instruments?

[Fezziwig]

I see you're having some lousy weather out there. Sorry to hear it. I didn't even know it ever snowed out there.

Well, since you're trapped inside and bored...

I'm afraid I'm not following your description of the relay. Is your relay oriented the same as in the picture? Mine is, and the contacts are three on the left stacked top to bottom (looking at the front of the block) and two stacked on the right, with a gap in the middle, not three left to right as I understand you to say. And are you saying the relay is NOT acting as a switch? Or it is? I think I'll probably have to be at the coach and be looking at the fuse block/relay to understand.

What sort of special set up are you referring to regarding the Vansco if it has been already programmed? Is that something that's DIY or something a specialty shop would do?

Thanks for the advice regarding retesting resistance in the wires after unplugging all the devices. I will do that next trip up.

I'm afraid I don't know how to check for stored engine codes. As far as the warning lights I don't remember any staying on except for the ABS light which has been on for about 90% since I bought it 3 years ago. The owner gave me some vague explanation that ended with "it works fine, the mechanic says ignore it" which is frankly is the only thing I retained.
I think if the wife and I are feeling better we'll go up to the coach this coming weekend and try out the new stuff I've learned and get more detail. I will update this post as soon as I do.

Thanks so much again!

[c_oneil]

You can't go by my profile for my location I don't even try to keep that updated. I'm in Arizona on the Phoenix east valley and the only snow I see is on the mountain tops.


I am reading off of wiring drawings for the fuse panel and its connections. In my drawing the fuse panel is 90 degrees clockwise from the picture you posted. The relay is in the bottom LH corner of the panel in my drawing instead of the bottom RH corner as per your picture. Below are the positions of the contacts in the fuse panel and where the wire that is connected to the back side of the fuse panel originates. I also added the color and identification printed on the insulation of each wire. So for your coaches orientation as looking at it from the FRONT of the panel:


top LH = BRN, 161 goes to Trans ECU connector P125, pin #31 (32 pin Gray connector)
middle LH = not used
btm LH = BLK, 2435S goes to ground
top RH = WHT, ABS 11T goes to ABS ECU connector P127, pin #12 (15 pin gray connector)
btm RH = WHT, 154 goes to Trans ECU connector P125, pin #27 (32 pin Gray connector) this is also wire marked 154 that you say is disconnected at the front Vansco.


You are absolutely correct the relay is just a switch in one circuit that is activated when it sees voltage from a second circuit. I didn't bother to sort out which wires were doing what but you can.



One of the Alpine coach assoc members has personally built a wire harness setup to connect 3 Vansco boxes. With it he can overwrite the program in a single previously programmed Vansco with a copy of the program in 2 Vansco boxes that already share a good program. It is not a DIY or specialty shop that I would know of that could help you. It will not fix a defective box.

[Fezziwig]

Once again you are a wealth of information, can't thank you enough. Look forward to getting back to the coach and apply all this new info.

Small world, Phoenix is where we bought the coach almost three years ago.

[Cinequip]

As a long time electronics tech, I recommend going back to what was last done prior to the new problem. You've identified that as replacing bulbs in the rear lenses. Because the Vansco behaves as a self restoring fuse (among other functions), i'm wondering if the new LED bulbs created a short circuit, OR a short was created in the wiring to the socket (if the assy was removed for service). The "fuse" should have restored itself, unless it's still shorted somehow. This is where I would check and re-check, before going deep anywhere else.

If a maintained short caused an internal failure in the rear vansco, then swapping front to back should result in different symptoms, which then confirms that the rear vansco has an issue. Or, the process of swapping will 'fix' it.

A short on an output line of one vansco, will not damage the other unit, nor shouldn't damage the first unit.

BTW, @engineermike is the person that has successfully programmed units acquired from elsewhere. However, I cannot confirm if he figured out a way to clear the unit to factory first. The factory may still sell the programming software, but it is expensive, and you would have to learn the language. They have proven to be difficult to work with. Mike didn't buy the software, he's doing all the programming off his coach network.

Hope something in my musing helps.

[Fezziwig]

Thanks so much for your reply, everything helps, even if not immediately apparent.

I thought about the bulb issue, but I neglected to mention that I replaced the original bulb and it lit which indicated to me that there wasn't a problem there with a short or a fuse. Maybe downstream? I did not remove the assembly FWIW.

I hope to be back to the coach soon and the first thing I will do is recheck all of my findings from before. The more I think about everything I saw and did the more I doubt everything I think that I saw and did! In particular I want to confirm the voltage readings at the relay connections, deal with the possibly disconnected white wire and eventually working to swapping the Vanscos front to back. I will post whatever I find. Thanks again.