The flaps increase the liftvermogen of the wing will reduce the stall speed during takeoff, low speed maneuvering and landing.

In accordance with the placement of the ‘Flaps Liver, to the right of the throttle quadrant, will this position be displayed on the "Flaps Position Indicator". These "Flaps Position Indicator" or Flaps gauge is located in the middle of the MIP top right corner of the Upper Eicas’. The "Flaps Position Indicator" is divided into 9 modes : UP-1-2-5-10-15-25-30-40.

The various positions are indicated by 2 needles (pointers). One for the left-wing TO Wing (Trailing Edge Flaps), and one for the right wing TO Wing. Furthermore, they also give an indication whether there asymitrie or skew arises between the two.

Brake Pressure
The brakes of a B737 is done via hydraulic pressure. The normal brake system is powered by hydraulic system B. The reserve or alternate brake system is done through the hydraulic system A.
If system B fails or the pressure is too low, will system A automatically the necessary hydraulic supply the pressure for the alternate brake system.

The pressure of the braking system is shown using the Hydraulic Brake Pressure Indicator’. That is located top right corner of the ‘Gear lever’. The scale of this gauge is divided into 1-2-3-4. Each digit is the PSI-pressure x 1000 (the pressure exerted by one pound-force on one square inch).
The Brake Pressure gauge gives the pressure in the Brake Accumulator’:
– Normal pressure : 3000 psi;
– Maximum pressure : 3500 psi;
– Normal oplaaddruk : 1000 psi.



In the world of the cockpitbouw we can say that Flight Illusion about the market leader in the supply of meters, clocks, or gauges. This company has also a large assortment available for anyone to his liking in can find.
The gauges of FI are made with quality materials and nicely finished. The drive of the FI gauges is done with steppermotoren.

A few drawbacks are that the FI gauges are quite expensive, not always easy to configure, and no realistic backlighting.
There is a small led on the front of the front plate that the front is lit, some of the FI gauges are equipped with a FLUORESCENT-type white led (Ice white or keukenlicht). There was no question of ‘backlighting’...

FI Flaps

Coincidentally, via the Prosim737 forum, I ended up with Custom Sim Parts. This company also makes gauges but for the time being to a limited extent. At the time of this writing that only the B737 MIP gauges such as Flaps and Brake Pressure and all of the Boeing 737 Overhead gauges.


What do the gauges of Custom Sim Parts so interesting :

  • Cheap;
  • All gauges can be custom-made to be made according to the wishes of the customer;
  • The backlighting is very realistic and beautiful;
  • Very simple installation and easy configuration;
  • Can be used with the Pokeys Microcontrollers + Led extension board and Prosim737 for a realistic backlight control.

When the first contacts with Custom Sim Parts is asked the size (diameter) of the gauge openings in the MIP or Overhead. This, together with the dimensions between the various boutgaatjes that the gauge must be confirmed.
To the size extra paint it can be also some close-up photos of the front and back of the MIP or Overhead join.


(The gauges in the picture are dummies)

On critical places where few or not enough space, due to the presence of a switch or a circuit board, then you can always try to find a solution, for example, the gauge may be smaller or in a different shape (e.g. diamond).
Afterwards, you will receive Custom Sim Parts of a drawing with the proposed desired dimensions for approval.

B737 Gauge dimensions

FlyEngravity MIP - Gauge dimensions

If the gauge openings in the MIP and OVH are equipped with a glass one can also the CSP-gauges ordering without glass on the front.

The control of the gauges is done using standard digital servos and this together with a Pololu Servo Controller. There are 2 versions :

The 6-Channel version is usually used for the MIP and the 12-Channel for the Overhead.

With the 12-Channel controller, one can, if necessary, MIP+OVH together, connect only the distance OVH>MIP to the Flaps and Brake Pressure gauge can be an obstacle ...
Therefore, it is easier for the MIP and OVH separate controller to use.
The remaining free ports on the controller can still be used for digital Inputs/Outputs. Unfortunately Prosim737 is not compatible with this Input/Output channels. Only the Servo channels will be recognized by Prosim737. That is a bit of a pity ...

This Pololu Servo Controllers are fully assembled. They are very small (30 mm x 20 mm) and are so easy to work behind the Mip or in the OVH.

The backlighting is done via an led behind the face plate is installed. The colour of the backlight can be choose, and is therefore optional.
The standard ‘warm white’. But one can also opt for an Amber-colour.

My FlyEngravity MIP and OVH-panels are all equipped with a warm-white backlighting. Therefore, the backlighting of the MIP and OVH gauges can also be fitted with warm-white color.

The backlighting may be powered via the Pololu-controller port with a supplied splitter cable.
It is also possible for the backlighting to focus on more realistic ways (see separate chapter).




Gauges can be powered with servos or steppermotoren. Both ways have their advantages and disadvantages.



The gauges of the Custom Sim Parts are equipped with digital RC servo's. Why?

  • Servos are much easier to implement than a stepper motor and much cheaper;
  • They can be connected to any standard servo controller what the gauges are universal or generally applicable make;
  • Servo-controllers are very cheap and there is a lot of choice in;
  • In the trade it is not easy to find a combination of a steppermotor with a controller at a similar price as in servo controller.



Which components have we all need to have the CSP gauges to install :

All cables and connectors are free of charge included (except the USB cable) 🙂



Flaps and Brake pressure




1. Install the Pololu drivers with the "Maestro Control Center":

Maestro Servo Controller Windows Drivers and Software (release 130422) (5MB zip)
This ZIP-archive contains the installation files for the Pololu Controller with the Maestro Control Center, the Maestro Command-Line utility and the Pololu Maestro Servo Controller-drivers for Windows.

2. Connecting the Pololu Servo Controller with the USB cable:

The Pololu Servo Controller should be connected to the pc where Prosim737 is installed. This happens with a USB Mini connection cable
(USB A, male <=>USB B, male 5-pin – 1.8 m).


3. Verify in "device Manager" in the Pololu USB Controller is installed:

CSP-Device Manager

4. Connect the servo of the gauge(s) and the backlighting with the controller:

The gauge is equipped with 2 small books cables : cables that come out of the servo and a bundle for the backlighting.
Both are with a splitter cable connected to the controller.


The flat plugs or connectors for the servos include 3 threaded ports : 1 white for the signal and the two others for the + (red) and – (black).


5. Connecting the controller with the 5V power supply

The 5V power supply one can get from an old pc power supply. Usually it is a homecockpit already equipped with such a’Power Supply’-container and can we have somewhere to drain. The flat plug for the controller has 2 terminals, + and – . The third is not used.




6. Open Maestro Control Center and make sure the controller is connected ("Connected to" followed by the correct card number).

CSP-Maestro Control Center1

7. Select the assigned channels in (0-1-2-3-4-5) by placing a tick in the check box (enabled);

8. Make sure to test the servo by moving the sliders. The pointer of the gauge together with the slider to move;

CSP-Maestro Control Center1 copy

9. Go to the ‘Channel Settings’ tab;

10. Set all channels ‘acceleration’, 1 (this should to the needles or pointers of the gauges easier to move);

11. Click ‘Apply Settings’ and close the program.

CSP-Maestro Control Center2



12. Start Prosim737;

13. Open Configuration/Drivers;

14. Enable Pololu support by placing a checkmark;


15. Go to the Gauges tab;

16. Scroll down to the correct gauge;

17. Choose the correct Maestro Controller in the drop-down list;

18. Choose the channel to which the gauge is connected;

19. To configure the sliders the correct setting of the gauge and press the OK button;


20. Open Flight Simulator and do a test – Make necessary corrections if needed.






As the connections of the backlighting above and plug the power cord into the wall outlet, then lights up the backlighting of all the gauges. Not a real Cold&Dark situation, and therefore also not realistic ...

The backlighting would, according to the Boeing manuals only active may be when the cockpit under AC power. This is after setting up the Ground Power, APU or active Generators.

How can we simulate it with the CSP-gauges and what are the possibilities?

  • Connect the backlighting of the gauges directly to 5V and place a switch in between. When the cockpit is switching to AC power, turn the switch on;
  • Linked to the switch from the ‘Ground Power’ (via a low voltage – high resistance – reed relay with a separate circuit from 5V or 12V). When the switch of the ‘Ground Power’ is used the relay to On/Off and backlighting switch.
    But then one is dependent on only the ‘Ground Power’ ...
  • A relay card with digital Outputs and compatible with Prosim737. In the Prosim737 configuration is a ‘Gate’ is used;
  • The use of Output channels in the Pololu Maestro Controller and link it to a ‘Gate’ in Prosim737 (as mentioned in previous).
    Unfortunately, this is not possible since Prosim737 is not compatible with the In/Output channels of the Pololu Controller. At the time of this writing, Prosim737 only to be used with the Pololu servo channels;
  • The use of a Pokeys Microcontroller and a corresponding ‘Led extension board". In the Prosim737 configuration is a ‘Gate’ is used.
    Since I'm one of the (first) users of the Pokeys card and the Led extension board " I have this option also be investigated together with Custom Sim Parts and FlightSimParts.eu (Wendy).
    After some testing I found this is the right, easiest and cheapest solution to the backlighting realistic.

Control of the backlighting through the Pokeys Microcontroller, Led extension board and Prosim737

Here follows a step by step approach to the Pokeys, the led extension board and Prosim737 to be configured so that the backlighting of the gauges starts to light up when switching on AC power:

  • Disconnect the splitters of the backlighting separately from the common bundle (Servo and backlighting). The 2 wires (+ and -) of the backlight lighting are now separate;
  • Connect the red (+) wires of the backlighting in parallel with each other and connects the latter to the common (+) of the Led extension board’;
  • Connect the black (-) wires of the backlighting in parallel with each other and connects the latter to one port of the Ledaansluitingen on the Led extension board".
    (The Led extension board is divided in 2 parts : one half is where the leds are connected, and the other half where the connection to the Pokeyskaart).
    On the led extension board can be one per port, several leds, and connecting this to max 300 mA. The CSP-gauge is equipped with a led of 20 mA. The backlighting of both gauges can therefore easily be jointly connected to a single port;
  • Then create a connection between a random port on the Pokeys Microcontroller (e.g. Port 2) to a port on the Pokeyszijde of the Led extension board". This port is opposite the port where we Ledverbinding have made (e.g. Port 8 to the ledzijde = Port 8 to the Pokeyszijde);

    Pokeys setup
  • Activate in the Pokeys configuration software (Poscope) the relevant port as a digital Output (in our example, Port 2);
  • Then we open Prosim737 Configuration – Gates, and we choose in the list ‘AC Power’ with out the correct Pokeysnr and the correct port (Port 2).
When we now have the cockpit under AC Power (e.g. Ground Power, APU, or generators) is the backlightverlichting of the gauges light up.



The prices of the Custom Sim Parts-gauges are very inexpensive.

Custom Sim Parts is very flexible and customer-friendly. The gauges are made according to the wishes of the customer. So I did the ‘Brake Pressure’, diamond-shaped, and the text " PSI x 1000’ change in a blue color...

The lead time of 3 to 4 weeks for the production and sending of the order will be respected.

The gauges of CSP are beautiful and nicely finished. The openings for the bevestigingsboutjes sit in the right place as previously passed and for which the confirm runs very smoothly. Ditto for the different connections.

When they get to the configuration step-by-step photos/videos to follow, this is an easy and simple task. A piece of cake ...

The backlighting of the gauges is realistic and wonderful to watch.

The needles or pointers of the gauges move quickly and smoothly without shock.

The contacts with the Custom Sim Parts (Tom Kaminski) are smooth and fast. Tom is very helpful for giving advice or seeking solutions.
Emails within 24Hr to answer.

For me, this was a ‘try-out’project with Custom Sim Parts a success all over the line.

Definitely recommended!





Coming soon ... !




Translated by Yandex.Translate and Global Translator