Accurascale class 37425 fitted with hm7000 sound decoder lighting malfunctions

[Steve-356187]

Fitted the accurascale class 37 with the hm7000 sound decoder downloaded the class 73 as no class 37 at moment all sounds seem to be ok but no internal cab & engine room lights etc

all external lights seem to work except the the centre lights front & back

hope someone can give me some help with this

steve

[96RAF]

Assuming you are using the HM DCC app and not direct DCC control . . .

Have you tried the Aux functions on page 3 of the functions control panel.

Of interest Steve what kit have you got the app loaded onto and what is your track powering arrangement. If not which DCC controller.

I ask as the Class 73 profile install has been giving the test team some grief recently.

thanks..

[Fishmanoz]

Apart from moving this to the HM | DCC forum, could the mods please remove “help required” from the title and insert “Lighting Malfunction”. That way, it will be obvious in future for people searching for solutions to similar problems.

[Steve-356187]

Thanks for reply tried the aux functions but no joy

app loaded on a 3 year old iphone

track powered by a hornby mains transformer on a test track as my hornby select became unrepairable & my layout is being updated

would it help to try another profile on the engine ?

Also thinking of purchasing the Roco Z21 digital control system & going for DCC sound fitted engines so there is less issues to overcome

[LMSFan72]

I suspect it’s the difference in available functions. I’ll try and find some time to compare the pin functions to what Accurascale used. Have you tried the different dip switch settings too - I haven’t looked at those for non-ESU sound decoders but I’ll give that a go too…

[Steve-356187]

Thanks for your interest tried loading different profiles but still no internal lights

[LMSFan72]

The HM7000 has only the 6 functions. I believe these are on the “standard” pins for a 21-MTC decoder. Accurascale have connected only the marker lights, tail lights and instrument panel lights to the first 6 functions. Now, they use the dip switches under the decoder to then make or break connections to other light connections for non-ESU decoders (ESU have 14 outputs which can control each light separately) but clearly they will not be able to operate everything. I have asked Accurascale if they can publish the detail of what each switch does but I would suggest that the engine room lights would be one of the least used so I suspect that is definitely one you’ll never be able to operate. I’ll update when I get any more detail.

[Andy-344679]

Any update on this? I have exactly the same issue. I have downloaded the Class 37 profile. Two of the Aux Light buttons turn the rear reds on, one for each direction. The other two aux light buttons do nothing. Is there a way to re program the function buttons? Thanks

[ColinB]

As someone said before it is because the HM7000 has not enabled all the function outputs. When I order a Zimo decoder for a Dapol diesel loco it has to be the D variant as opposed to the C one as on a C version 2 of the function outputs are not enabled. Now I think on a Zimo there is a CV that you can write to to enable them. I must admit I took the easy option, I bought the loco with sound fitted. If you want decent sound specially tailored to that particular loco it is the easiest and surprisingly the cheapest option. I don't know if Hornby have this magic CV to enable them and more importantly the hardware to drive them.

[96RAF]

If you read the famous manual it clearly states those 2 aux functions are low level logic only, not full voltage hardware function outputs. Of course the lighting will not work correctly, as you need a full potential 6 function decoder not a 4+2 decoder for that loco.

This has been covered on the forum a couple of times previously.

[ColinB]

You can buy a driver pcb for the extra two functions off BLW technical services on EBAY, there probably is enough room to fit it.

[Andy-344679]

If you read the famous manual it clearly states those 2 aux functions are low level logic only, not full voltage hardware function outputs. Of course the lighting will not work correctly, as you need a full potential 6 function decoder not a 4+2 decoder for that loco.

This has been covered on the forum a couple of times previously.

 

 

Excellent, please can you post a link? I've tried the search bar on here and it throws up thousands of results. Many thanks.

[SteveM6]

All the relevant links are in the pinned posts at the top of this section of the forum.

[Fishmanoz]

At the top of the HM | DCC forum, not this one.

[SteveM6]

My mistake Fishy, but it shows once again, a post in the wrong section. Should already be in HMDCC.

[ColinB]

Perhaps next time order the loco with the factory fitted sound option. By my calculation the difference is about £89, an HM7000 with Powerbank is £86, so for £3.00 more it saves all the aggro and the sound is tailored for the actual loco and all the lights work. I do the same calculation for all the locos I buy. Hornby are the only ones I buy without, mainly because they they don't do the option. I just got fed up with the issues taking the loco apart to fit DCC sound and found generally the factory fitted option was cheaper than buying a sound decoder plus postage.

[Fishmanoz]

My mistake Fishy, but it shows once again, a post in the wrong section. Should already be in HMDCC.

 

 

Agreed.

Mods to move please.

[LMSFan72]

Coming back to the issue here. The Accurascale 37 is fitted with a PCB designed in conjunction with ESU. I believe it uses the SUSI pins on the decoder to talk to the PCB to use additional functions. It’s not really anything to do with the 2-logic functions in the HM7000 which would also be logic on the Loksound v5. It’s simply that the 37 is specifically designed for an ESU decoder.

[LMSFan72]

Coming back to the issue here. The Accurascale 37 is fitted with a PCB designed in conjunction with ESU. I believe it uses the SUSI pins on the decoder to talk to the PCB to use additional functions. It’s not really anything to do with the 2-logic functions in the HM7000 which would also be logic on the Loksound v5. It’s simply that the 37 is specifically designed for an ESU decoder.

[ColinB]

Yes LMSFan72, it uses specific pins on the ESU decoder the same pins that any other decoder has. It is just whether those pins have the right signal on them. The Hornby one doesn't, if you order the D option (I think I got that right) of a Zimo decoder then than will be connected properly as will the Dapol Imperium with the right version. So it depends which version of decoder you buy. Now from what I can gather the HM7000 in all its guises doesn't enable those extra 2 functions and from what I am reading has no configuration to make it work. So my suggestion is if you want all the lights to work is move the HM7000 to another loco and buy either a Zimo or ECU sound decoder, remembering to specify that you need all 6 functions enabled (2 for standard lights, plus 4 extra). I did think you could use one of those devices on EBay to drive the two extra functions but that would mean breaking into the connection on the PCB which is not a good idea. Hornby are a bit behind the rest on lighting generally only using 4 functions at the most, so they obviously haven't found a need to configure the other 2 correctly.

[LMSFan72]

@ColinB

I totally agree that if you want all functions to work you need the right decoder. The only decoders that will do that are the ESU v5 - either Lokpilot or Loksound.

However it’s not simply the case of the functions being logic level - actually the same pins on the ESU that the HM7000 has functions on operate the same way - pin 4 (AUX4) and pin 13 (AUX3) are logic level on both. That logic v full output on 6 function decoders is the issue we commonly come across on 21-pin decoders. This one is different:

The Accurascale 37 requires 15 functions for everything to operate as designed. The 21-pin socket doesn’t have enough pins for 15 functions. It uses the 2 SUSI pins on the decoder (pins 5 and 6 I think) to “talk” to the circuits built into the loco PCB that has those functions built on it. Only an ESU chip can talk to the board that way. A Zimo cannot. That is why Accurascale specifically have the dip switch settings designated for “ESU” and for “non-ESU”. You’ll notice that the language never refers to NMRA standard or the number of functions. I originally thought that was just their terminology and somewhat “woolly” but it is actually very precise!

[ColinB]

I see LMSFan72, pins 5 and 6 are defined as clock and data it is similar to how we used to do things when we ran out of pins. So a good move to buy it with sound fitted. So where did you find this information? I just assumed they did it like Bachmann and Dapol, either way an HM7000 is not going to work.

[ColinB]

Isn't this the same system Hattons used on their class 66? I remember having to buy a 10 function decoder for my one. Looking at my function table for my class 37 there are 9 functions available for switching on the lights. 2 for F0, F17, F18, F19, F20, F21, F22, F23. It lists 14 AUX plus 2 for front and rear light, but I assume these are internal to the ESU device depending on loco direction unless there is a command on DCC to drive AUX functions.