How to access service in app.module?

[mackelito]

I have a auth service that I want to access to set some values in restangularInit

export function restangularInit(RestangularProvider, AuthService) {
  RestangularProvider.setBaseUrl('api');
  RestangularProvider.setDefaultHeaders(
    {'Authorization': 'Bearer [replace this :) ]'},
  );
}

can´t find out how to use my AuthService.. it just stays "undefined"..
Any help is appreciated!

[mackelito]

More code to give a better context..

    import { BrowserModule } from '@angular/platform-browser';
    import { NgModule } from '@angular/core';
    import { FormsModule } from '@angular/forms';
    import { HttpModule } from '@angular/http';
    import { MaterialModule } from '@angular/material';
    import { FlexLayoutModule } from "@angular/flex-layout";
    import { RestangularModule } from 'ng2-restangular';

    // Components
    import { AppComponent } from './app.component';
    import { ProductComponent } from './components/product/product.component';

    // Services
    import { AuthService } from './services/auth.service';

    export function restangularInit(RestangularProvider, AuthService) {
      console.log(AuthService);
      RestangularProvider.setBaseUrl('api');
      RestangularProvider.setDefaultHeaders(
        {'Authorization': 'Bearer d7b2e9f56a22646a22e1ee348ab2f85bdb967b56'},
      );
    }

    @NgModule({
      declarations: [
        AppComponent,
        ProductComponent
      ],
      imports: [
        BrowserModule,
        FormsModule,
        HttpModule,
        MaterialModule,
        FlexLayoutModule,
        RestangularModule.forRoot(restangularInit)
      ],
      providers: [
        AuthService
      ],
      entryComponents: [ProductComponent],
      bootstrap: [AppComponent]
    })
    export class AppModule { }