Schaudt DT201 Display Circuit Diagram anyone?

[StuartO]

My 2006 Hymer B674 has a defective step alarm - the thing which is supposed to sound off if the electric step is down when the engine is started. The circuit to the microswitch at the step is OK and appears to terminates at one of the connectors on the DT201. An alarm buzzer is mounted on the PCB of the DT 201 and I think that might be the problem.

 

Does anyone have a circuit diagram for the DT201 please?

[bounty hunter]

Stuart

This hopefully helps.

John

 

https://www.manualslib.com/manual/941397/Schaudt-Dt-201-B.html?page=22#manual

 

[StuartO]

bounty hunter - 2021-05-28 4:42 PM

 

Stuart

This hopefully helps.

John

 

https://www.manualslib.com/manual/941397/Schaudt-Dt-201-B.html?page=22#manual

I already have that, in the DT201 User Guide. The labelling of the connections is useful on that diagram. It’s the PCB circuitry I’m after and I suspect that Schaudt don’t release that.

[Thai Bry]

StuartO - 2021-05-28 1:28 PM

 

My 2006 Hymer B674 has a defective step alarm - the thing which is supposed to sound off if the electric step is down when the engine is started. The circuit to the microswitch at the step is OK and appears to terminates at one of the connectors on the DT201. An alarm buzzer is mounted on the PCB of the DT 201 and I think that might be the problem.

 

Does anyone have a circuit diagram for the DT201 please?

Hi Stuart

 

We don't have a circuit diagram for the DT201, however, when we had some work done by the late Allan Evans, he gave me a full english version of the DT201, together with the total values that you should enter into the DT201 for all the accessories that you have.

 

Our pin for the DT201 = 8251, and total values = 773. This includes the step alarm.

It may be worthwhile if you re entered the values again, it may cure your problem, seeing as the circuit to the microswitch is OK.

 

If you PM me I'll send you the parameter values if you so wish.

 

Regards

Brian

[StuartO]

Thai Bry - 2021-05-29 7:07 AM

 

StuartO - 2021-05-28 1:28 PM

 

My 2006 Hymer B674 has a defective step alarm - the thing which is supposed to sound off if the electric step is down when the engine is started. The circuit to the microswitch at the step is OK and appears to terminates at one of the connectors on the DT201. An alarm buzzer is mounted on the PCB of the DT 201 and I think that might be the problem.

 

Does anyone have a circuit diagram for the DT201 please?

Hi Stuart

 

We don't have a circuit diagram for the DT201, however, when we had some work done by the late Allan Evans, he gave me a full english version of the DT201, together with the total values that you should enter into the DT201 for all the accessories that you have.

 

Our pin for the DT201 = 8251, and total values = 773. This includes the step alarm.

It may be worthwhile if you re entered the values again, it may cure your problem, seeing as the circuit to the microswitch is OK.

 

If you PM me I'll send you the parameter values if you so wish.

 

Regards

Brian

Don’t follow what you mean by values = 773. When I enter the 8251 code I get a screen showing water tanks but it won’t respond to any keys except “12v” which returns the DT201 to normal service.

 

Maybe the DT201 is faulty so I’m thinking about installing a separate buzzer to provide a step warning.

[Thai Bry]

StuartO - 2021-05-29 10:04 AM

 

Thai Bry - 2021-05-29 7:07 AM

 

StuartO - 2021-05-28 1:28 PM

 

My 2006 Hymer B674 has a defective step alarm - the thing which is supposed to sound off if the electric step is down when the engine is started. The circuit to the microswitch at the step is OK and appears to terminates at one of the connectors on the DT201. An alarm buzzer is mounted on the PCB of the DT 201 and I think that might be the problem.

 

Does anyone have a circuit diagram for the DT201 please?

Hi Stuart

 

We don't have a circuit diagram for the DT201, however, when we had some work done by the late Allan Evans, he gave me a full english version of the DT201, together with the total values that you should enter into the DT201 for all the accessories that you have.

 

Our pin for the DT201 = 8251, and total values = 773. This includes the step alarm.

It may be worthwhile if you re entered the values again, it may cure your problem, seeing as the circuit to the microswitch is OK.

 

If you PM me I'll send you the parameter values if you so wish.

 

Regards

Brian

Don’t follow what you mean by values = 773. When I enter the 8251 code I get a screen showing water tanks but it won’t respond to any keys except “12v” which returns the DT201 to normal service.

 

Maybe the DT201 is faulty so I’m thinking about installing a separate buzzer to provide a step warning.

The values in the DT201 are in the set up menu Stuart.

 

Each symbol on your DT201 has a value.

Step = 1, Solar current = 4, etc. etc.

 

If in menu mode all you are getting is a screen showing water tanks, then I'm not too sure what your problem is.

 

Apologies if I've confused you even more.

[Thai Bry]

I do have the full English version of the DT201, showing values for each symbol that's available to be programmed in to the DT201.

 

 

[StuartO]

Thai Bry - 2021-05-29 11:32 AM

 

I do have the full English version of the DT201, showing values for each symbol that's available to be programmed in to the DT201.

That could be very helpful; could you send me a copy? I will PM my email address.

 

The Schaudt 12v schematic wiring diagram for my Hymer (a B674) shows the step circuit and all the components connect to a control unit/relay called an EMS02 and that would be the place to try and connect alternative buzzer. But so far I cannot find it's physical location. The cables seem to lead into the boiler compartment which is a bit cluttered - I'll keep looking.

[StuartO]

This is what the EMS02 looks like. I suspect the four way connection is for the power and motor cables and the six way is for everything else.

[Alanb]

Stuart,

 

You may find some info about the EMS 02 on this thread, but I do not think that it will suit your purpose. As you are aware the "IN" indication switch on an Omnistor step is typically connected to earth at one side, and used to control auto retract relay and/or step out warning. It does not enter the EMS 02 module.

 

Alan

[StuartO]

Here is the sub circuit for the 12v step from Schaudt's 12v wiring diagram for my B674. It's schematic so it merely illustrates the connections and cable sizes and colours of the components of the circuit. There is no mention of a buzzer at all. Trittstufe means Step, Schalter Eingang Trittstufe is the in/out operating switch and Schalter Fahrerhaus Trittstuffe is the microswitch which detects that the step is out.

[Alanb]

Stuart,

 

Unfortunately my German is extremely limited. Given some context, I can manage to understand a few technical words.

 

Haus = house, so checking online "fahrerhaus" means drivers cab. Schalter means switch or circuit breaker, so Fahrerhaus Schalter means drivers cab switch.

 

Alan

[Robinhood]

Instructions for most Schaudt equipment is downloadable from their website (though they insist on sending a link by email for items you select)

 

Though most languages are available, some of the smaller items in particular only have instructions in a limited number of languages (including German, natch).

 

The EMS02 is one of these; from perusing the text, I can't find anything helpful regarding the step alarm (and feel that this must be controlled from elsewhere - albeit sensing the step and ignition situation).

 

The attached diagram expands (if only slightly) on the wiring schematics you already have.

[StuartO]

Alanb - 2021-05-30 11:04 AM

 

Stuart,

 

Unfortunately my German is extremely limited. Given some context, I can manage to understand a few technical words.

 

Haus = house, so checking online "fahrerhaus" means drivers cab. Schalter means switch or circuit breaker, so Fahrerhaus Schalter means drivers cab switch.

 

Alan

 

Spot on - and my mistake. That makes the Schaudt wiring diagram even more incomplete because the step microswitch is also missing. If I ever find the control/relay unit it will be interesting to discover if the brown & white cables (from the step microswitch route to there with the purple and orange motor cables.

 

The step motor has just these two cables and positive to purple (and negative to orange) extends the steps and reversing the polarity retracts them. The step alarm sounds if the steps are extended (and microswitch closed, connecting brown and grey) and the ignition is switched on. I am starting to think the brown and grey pair for the microswitch are routed to the DT201, which also must have a feed indicating that the ignition circuit is live. However on my DT 201 there is no sign of a brown and grey pair so there may not be a direct connection.

 

The thing about 12v autoelectrics is that the circuits are logical - unless electronics have crept in somewhere!

[Alanb]

Stuart,

 

Regarding the location of the EMS 02 relay unit, see Whiskeymac's thread that I linked to previously. The last post made by Whiskeymac on 16 July 2019, describes the location of the EMS 02 in his Hymer. Perhaps yours is in a similar place.

 

The tail cables of the step motor will not be of infinite length, so an intermediate connector is to be expected.

 

Alan

[StuartO]

Alanb - 2021-05-30 6:06 PM

 

Stuart,

 

Regarding the location of the EMS 02 relay unit, see Whiskeymac's thread that I linked to previously. The last post made by Whiskeymac on 16 July 2019, describes the location of the EMS 02 in his Hymer. Perhaps yours is in a similar place.

 

The tail cables of the step motor will not be of infinite length, so an intermediate connector is to be expected.

 

Alan

 

I haven’t tried following the cable routing from the step, which enters the MH through the floor behind the fridge but that’s obviously worth doing - not least because the brown and grey pair from the microswitch probably divert to head for the DT201 at the inevitable cable junction you suggest is likely. I’ll take the lower fridge vent out to have a look around.

 

My EMS02 controller/relay is likely to be in the same location (heater cupboard) as Whikeymac’s and likely to require the use of mirrors to reveal exactly where it’s hiding! Fortunately mine seems to be working fine; it’s the mysterious additional circuitry for the microswitch and buzzer which I need to track down.

[Alanb]

StuartO - 2021-05-31 8:41 AM

 

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it’s the mysterious additional circuitry for the microswitch and buzzer which I need to track down.

Agreed. May you find that which you seek.

 

Alan

[StuartO]

And I think I have at least localised the fault.

 

Firstly I followed the cable runs and found no poor connections or disontinuities and the step motor switching works as it should, so it is just the warning buzzer which isn't working - and that seems to be embeded into the DT201 display panel PCB, which is beyond my skill set to diagnose and fix.

 

A single black cable provide a 5 volt positive indicator to terminal 2 of Connector X9 (on the following diagram) and the DT201 circuitry does the rest, detecting whether the vehicle ignition is on and if so sounding the buzzer - except in my case it doesn't, so the fault is somewhere on the Dt201 and possibly the embedded buzzer unit.

 

Presumably if I buy a replacement DT201 and install it the buzzer will work but these are expensive, it's a small fault so I will try to replace the buzzer first if I can.

 

Thanks for all your help guys ......

[Brian Kirby]

Just a thought in case it may help Stuart. Do you know what make your step is? If Omni/Thule (which is the same as ours, although the step type is different) the unit is available in two versions.

 

One has an auto-retract function via a relay that retracts the step when the ignition is turned on. The other has either a warning buzzer or a warning light that buzzes or lights up accordingly if the ignition is turned on with the step extended.

 

From the various Thule documents I have those bits all come with the step (although it is not clear whether this is true for the actual light/buzzer, or whether the installer is to source them. However, it seems reasonable that all the parts would be supplied with the step. The actuating switch to extend/retract the step is definitely a Thule supplied item.

 

I ask, because there is a fairly large amount of documentation downloadable from the Thule website, including step wiring diagrams and installation instructions. I know, because I downloaded some to use while wiring an external light to the step microswitch so that the light could not be switched on with the ignition on! :-)

 

If this is true for your step might it be that Hymer merely install the Thule kit using their bits, in which case might the buzzer be mounted in a different location, rather than being integrated into a piece of Schaudt kit? That would appear simpler and more logical, in that the buzzer is part of the step installation and not part of the vehicle electrics - although it must obviously get it power from a designated supply point. It just seems odd to solder a piece of legally required safety kit to a PCB, meaning that it is both difficult, and costly, to replace. After all, buzzers do fail.

[Thai Bry]

StuartO - 2021-05-31 3:35 PM

 

And I think I have at least localised the fault.

 

Firstly I followed the cable runs and found no poor connections or disontinuities and the step motor switching works as it should, so it is just the warning buzzer which isn't working - and that seems to be embeded into the DT201 display panel PCB, which is beyond my skill set to diagnose.

 

Presumably if I buy a replacement DT201 and install it the buzzer will work but these are expensive, it's a small fault so I will try to replace the buzzer first if I can.

 

Thanks for all your help guys ......

Hi Stuart

 

Just as a thought, if you're looking at a replacement unit, have you tried to contact Schaudt direct. They're very helpful.

Also, as Brian K has stated, could it be just the step.

Our buzzer sounds in the cab area, it seems to be behind the dash around the steering wheel area. Could it be the buzzer unit that has failed.

 

Just a thought.

 

Brian

[Brian Kirby]

Thai Bry - 2021-05-31 4:31 PM.........................Could it be the buzzer unit that has failed. Just a thought. Brian

Good day Brian! Or even that a wire has come adrift from it. Up behind the dash was sort of where I would have expected it to be, if for no other reason than it is closer to the driver, so more likely to be heard.

[StuartO]

Hymer seem to get Schaudt to design their electrical installation, based on using Schaudt components. Hymer also buy in other accessories as necessary but will then “Hymerise” them if appropriate, as for example with the Omnistor electric double step, re-badged as a Hymer step. Schaudt incorporate the step (now sold under the Thule brand name) into their circuit design for Hymer, in this case using a Schaudt controller/relay. The Thule step can be used in two basic ways, either automatically retracting the steps if the vehicle’s engine is started or not, in which case a warning buzzer can be triggered. The current Thule step is virtually the same as the Omnistor step of 20 years ago and the circuit options are also unchanged.

 

My 2006 Hymer had an Omnistor 440 step, since replaced with a Thule 440 which is effectively the same, down to the colours of the electrical cables. It was installed as a direct replacement using the same cable connections and the new step worked responded to the same control switches in exactly the same way. The warning buzzer has developed a fault, initially intermittent, now persistent, and the buzzer used to sound from the direction of the DT201 display unit, over the habitation door. The fault has been narrowed down to the DT201 as described above.

[Alanb]

The Omnistep on my 2006 IH Tio R was originally connected to autoretract whenever the ignition was turned on. Not a good idea, as after my checking the odometer reading for my log, poor Joyce nearly fell past a missing step. There was also step out warning LED, which I realised that I was not checking when moving off. A flashing LED was substituted with little improvement. A modification was to use the CBE simulated D+ signal to retract the step. Having this signal available, I then added a proprietary miniature warbler as a second step out signal.

 

Sequence now is ignition ON - flashing LED, engine started - step retracts, with warbler sounding and LED flashing until the step has retracted. To avoid any possible back feeds, I used blocking diodes in series with the auto retract relay coil, the warning LED, and the warbler.

 

Alan

[Thai Bry]

Brian Kirby - 2021-05-31 5:51 PM

 

Thai Bry - 2021-05-31 4:31 PM.........................Could it be the buzzer unit that has failed. Just a thought. Brian

Good day Brian! Or even that a wire has come adrift from it. Up behind the dash was sort of where I would have expected it to be, if for no other reason than it is closer to the driver, so more likely to be heard.

 

Our Hymer set up must be different to Stuart O's. As we have a switch on the dashboard, where we can retract our step, if we have not retracted it via the switch next to the habitation door.

 

Hence my question regards the switch and buzzer. We also had our 2 step unit replaced a few years ago with another one. Our Original had a Hymer logo on it. The replacement one is from Fiamma or Omnistor, without any logos

 

 

[StuartO]

Thai Bry - 2021-06-01 6:41 AM

 

Our Hymer set up must be different to Stuart O's. As we have a switch on the dashboard, where we can retract our step, if we have not retracted it via the switch next to the habitation door.

 

Hence my question regards the switch and buzzer. We also had our 2 step unit replaced a few years ago with another one. Our Original had a Hymer logo on it. The replacement one is from Fiamma or Omnistor, without any logos

I also have a switch (a momentary press button) on the dashboard and that continues to work perfectly; I believe the cables for this will go to the Schaudt EMS02 controller/relay to have their effect.

 

If you had a dealer replace the step and a Fiamia product was used you might well have ended up with a different circuit configuration whereas in my case the replacement step was a Thule 440 (virtually the same as Omnistor 440) and I installed it myself using exactly the same circuit connections - including the cable to the DT201 and its (currently non-functioning) warning buzzer. I'm now pursuing repair of my DT201 so I get the warning buzzer working again.