Speedometer Output

The Speed output can be used to drive cluster speedometers or data logger. This output is a square wave signal and has adjustable pulses to calibrate external speedometers. See the tuning software for more details.

The Orion output is a ground square wave signal with a 1K pull-up resistor to 12V. Most digital speedometers can be connected directly but there are 2 main types. A third type is stepper control speedometers that is controlled by the OEM TCU. This one cannot be done and it is best to keep the OEM TCU running by providing it the normal pulses it is used to.

Digital Speedometers
This type can be connected directly on the ECU Speed output. The positive and negative is usually supplied by the dash electric connections.

Magnetic Pickup Speedometers
This type requires a spike circuit that is based around earth. There is no fixed circuit that will work with all of them. Since the 12 volt square wave only goes to earth it does not trigger these speedometers. In this case a 10uF 25V capacitor can be used to isolate the DC which will generate a +/-6 volt spike circuit around earth. If you use a polarized cap put the positive to the TCU side. If their ref wire is 12 Volt you may need to turn the cap around. If you use a non-polarized cap you should be ok for both types.

You may need to add a 1K resistor in option 2 for their electronics. In some cases, they require a reference voltage on their sensor wire.

In some cases, you may require a 1K resistor on both sides as in option 3. This to ensure more energy through the capacitor. You may also need to tweak the capacitance in some cases. There is no fixed circuit that will work with all of them.

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