The speedometer output generates an output frequency based upon the selected speed variable. The output frequency generated is suitable for calibration of digital speedometers. A sweep function can also be used at key on to run the needle over the entire range of the speedo.
The output frequency in Hz is the current speed in kph * multi + offset.
Settings:
The Auxiliary Output being used to control the speedometer gauge.
The speed source to use for Speedo Out.
The maximum Speed (Assuming correctly set Multi and Offset) applied to Speedo Out during normal operation. This can be used to prevent damage to the speedo due to running it past the end or to prevent an OEM ECU seeing the actual vehicle speed above a certain point.
The ratio of output frequency to input speed. If set to 1.0 the output frequency will be the same as the input speed. If set to 2.0 the output frequency will be twice that of the input speed. If set to 0.5 the output frequency will be half that of the input speed.
Added to the input speed over the entire range, is used to correct for when there is an offset or zero error in the gauge. Note the Multi must be set correctly before this offset value is representative of the speed units being used.
Activates the key on speedo sweep feature. This feature causes the speedo to sweep round to the Sweep Speed at key on then back to 0.
The maximum frequency applied to the speedo at key on if Key On Sweep is enabled. Adjust this using trial and error to make the speedo sweep to the desired speed.
The time taken to reach the Sweep Speed. Once the correct Sweep Speed is setup, this is the time it will take the gauge needle to reach its peak position.
Example Setup 1
In this example we will assume that a vehicle is equipped with a digital speedometer and hall effect speed transducer. For some reason (maybe a trans change or wheel size change) the speedo calibration is no longer correct. The speedometer reads 80 kph when the vehicle is travelling at 100 kph. To correct this situation the following must be performed:
1.Break the wire from the transducer to the speedo. Connect the transducer to a Digital Input (eg DI 3).
2.Configure DI3 as a speed input including correctly calibrating it (e.g. Set GP Speed 1 Source to DI 3 and adjust the Calibration value until it is correct).
3.Wire an auxiliary output to the speedo (eg Aux 3).
4.Set the Speedo Out 'Output' setting to Aux 3.
5.Set the Source to the speed source that has been setup in step 2.
6.Adjust the Multi until the speedometer value increases at the same rate as the ECU.
7.If the speedometer has a constant offset, say always reads 3 kph low then the Offset setting can be used to correct this, an offset value of 3 in this example.
Example Setup 2
In this example we will assume that a vehicle is equipped with wheel speed sensors connected to a CAN wheel speed module, and this data is sent to the ECU over a CAN bus. We wish to send the speed of the driven wheels out from the ECU to the factory dash.
1.Setup the CAN to receive the wheel speed from the CAN wheel speed module.
2.Setup the speeds sources that are receiving from CAN (e.g. Set LF Wheel Speed set to CAN DI 1 Frequency and so on)
3.Setup the driving and driven wheel speed sources.
4.Wire an Auxiliary Output to the dash.
5.Set the Speedo Out 'Output' to the Auxiliary that is wired to the speedometer.
6.Set the Source to Driven Wheel Speed.
7.Adjust the Multi and offset until the speedometer value matches the ECU value.