GTR RaceROM V9 Map Switching

Owned by Paul Blamire
Mar 19, 2024
6 min read

Map switching on the latest version 9 RaceROM is different to previous versions. The main difference is that the MapSwitch mode is no longer displayed on the tacho, this is intentional, it is not a bug. If you have been used to seeing the tacho needle flick to 1,23 or 4000rpm in the past, you will instead need to look at the coolant display.

Because of the loss of the tacho display for map switching, the initial releases of v9 had trouble being able to display the mapswitch mode and ethanol content for users that were not using ECU Connect.

This is been improved from patch version 56985 which also includes bugs related to the converting of data for Fahrenheit displays on US cars, while displaying custom data.

Detailed Operation

To show value on coolant gauge for example, ethanol content.

  1. Press and hold Cruise Control Cancel button

  2. After a short delay set by Coolant Temp Display Short Press Delay the data selected from the list Coolant Temp Display Options (Short Press) will be shown

  3. Keep pressing the Cruise cancel button to keep displaying the data for a time set in Map Switch Button Delay after which time Map switching is entered.

To show the current Map Switch Mode

  1. Press and hold the Cruise Control Cancel Button for time in Map Switch Button Delay and the the value set in Coolant Temp Display Options (Mapswitch) will be sent to the gauge. By default his is set to Fixed Value and this is the recommended setting for most users.

  2. Release the Cruise cancel button and the gauge will return to normal after a few seconds.

To change current Map Switch Mode

  1. Press and hold the Cruise Control Cancel Button for time in Map Switch Button Delay and the the value set in Coolant Temp Display Options (Mapswitch) will be sent to the gauge.

  2. Release the cruise cancel button and use the cruise control up/down buttons to scroll up and down the modes. Users only have 2 seconds to start adjusting the set mode before map switching is exited. The maximum mode is set in Map Switch Modes Enabled but set to only mode 1 by default.

  3. Once the desired mode is selected, release cruise up/down toggle and either wait 2 seconds, or give the cruise cancel button a quick press to exit immediately.

  4. The new mode is only entered once the switching process is exited, not while the new mode is being selected.

Maps

Coolant Temp Display Fixed Values

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These are the values that are shown once Map Switching is active and the drive can either view the current mode or select a new mode. Typically these are set to 1,2,3,4 for cars with the display in Celsius, but occasionally set as 10,20,30,40 for cars using Fahrenheit displays to avoid problems that occur when the Nissan display rounds the incoming data (which is always in Celsius). Some tuners may use this to enter an octane rating for fuel such as 95,97,99,102 correspond to available RON fuels in continental Europe.

These values are only shown if the option in Coolant Temp Display Options (Mapswitch) is set to “Fixed Value”.

Coolant Temp Display Options (Mapswitch)

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Set to Fixed Value by default this allows the user to see the current mode and/or select a new mode. However some users will not change map switch mode, or may use ECU connect exclusively for map switching, in this case the an alternative value can be shown while in mapswitching mode.

This can be useful for diagnoses or to display a custom map value, which in some situations could selectively show map switch mode.

If (Coolant Temp Output is Fahrenheit) is checked in the Enable Special Features option list, the value is manipulated to show the desired value in Fahrenheit on a Fahrenheit gauge only while displaying something besides the normal coolant temperature.

 

Coolant Temp Display Options (Normal)

This is used to set what is sent to the gauge in normal operation. Be aware this data is also sent to the TCM and the analogue gauge in the cluster, so changing this may result in unpredictable side effects.

However, this can be used to display important info while dyno testing on a temporary basis.

Coolant Temp Display Options (Short Press)

By default this is set to Stock Operation so the user will not notice anything different. However, if you want to be able to show ethanol content or any of the other options, it’s the ideal option.

The value is show all the time the users is holding the cruise cancel button until you enter map switching. With the default settings this gives a brief window to spot check something like ethanol content. If you want to give the user more time to look at these values, you should increase the delay in Map Switch Button Delay but realise that in doing so, you will also increase the time it will take to change maps.

Coolant Temp Display Short Press Delay

This is just a debounce delay. No change to the gauge display is made until you press the cruise cancel button for this time.

Map Switch Button Delay

The user needs to press the cruise cancel button for this time in order to enter map switching. Be aware the time starts from the moment the cruise cancel button is pressed, and includes the time delay in Coolant Temp Display Short Press Delay.

Map Switch Mode 1/2/3/4 Description (ECU Connect)

This serves two purposes. It is shown in ECU Connect as a reminder to what each mode does, but it can also act as a reminder to the tuner, even if the user doesn’t use ECU Connect.

Map Switch Modes Enabled

Number of modes available to the user, by default this is just 1 so disabling map switching. However the option to show other values with a short press of the Cruise button will still function with this set to Mode 1 Only (No Map Switching)

Enable Special Features (Coolant Temp Output is Fahrenheit)

The Gauge display on the MFD always receives it’s data in Celsius, even on cars that display the data in Fahrenheit. This option ensures that when sending data other than the coolant temperature the most appropriate value is sent on the CANbus.

Rounding issues mean some values will not display correctly!

If you want to send a value of 85 for 85% ethanol for a car using an MFD set in Fahrenheit the ECU needs to send a value of 29 which is the closest round number to 85. However 29 Celcius is actually only 84.2 Fahrenheit, and 30 Celcius is 86 Fahrenheit. Since the data is only send to the nearest whole degree Celcius, there will be some slight anomalies!

By default this is set to off, so for US cars, it is normal to have to check this option.