Hey, what's going on? You plugged in your PlayStation or XBOX pad in hopes that you'll be able to play GTA on your PC just like you used to play on the console, and for some reason you can't make the controls work properly? You can't use full possibilities of your brand new, XInput-compatible pad? Maybe you want to refresh your childhood memories after ages of playing IV and you're sick of the old-fashioned controls?
If any of these apply to you, GInput is the mod you've been looking for! This modification completely rewrites GTA controls handling and ditches DirectInput in favour of XInput. This way, your PlayStation 3 and XBOX 360 pads will be handled by the game just perfectly, taking advantage of all their features, including analog triggers. If used with DualShock 3 controller and SCP Driver Package, it can go as far as making full use of SIXAXIS feature, just like some PS3 titles do!
This modification features:
Complete XInput support, so pads are mapped to match console versions perfectly (including Start button, which can't be mapped on PC version without this modification).
Proper vibration support - something that was cut from all PC versions of the game!
FIVE (TWO in San Andreas) different control mappings - four setups matching PS2 selectable setups and fifth one being a recreation of GTA IV controls!
Pad buttons in In-Game helps, replacing PC key names (depending on user's choice, either PlayStation or XBOX buttons are shown).
An INI file with tons of options - including toggleable vibration, selecting controls setup, Invert Look option from console versions, axis inversion options from San Andreas and more!
Automatic switching between keyboard & mouse and pad controls, basing on last device input.
Support for Guide/PS button. The button is fully functional and can show your Steam Overlay menu if you launched the game via Steam!
Cheats input from the pad. Use classic PS2 cheats on PC!
Full co-op support in San Andreas - the game can make full use of two pads or bind the first pad to second player, so co-op can be played even if only one pad is connected
Increased support for DualShock 3 controllers and SCP Driver Package - including pressure sensitive buttons and SIXAXIS accelerometers
Why? Use it.
Oh okay, didn't notice you're using your own SCM? Well, then you're probably still using code parts which check for the controller set. Since IV controls is a new set, the code probably lacks the case for it and the helps don't show.
If this SCM has stock SCM parts, you still could try using SCM fixes toggle.