Laravel 5.2 cannot update record - laravel

Question

I cannot seem to update my record.
My controller
public function add()
{
return view('cars.add');
}
public function edit($id)
{
$car = Cars::whereId($id)->firstOrFail();
return view('cars.edit', compact('car'));
}
public function store(CarFormRequest $request)
{
$car = new Cars(array(
'name' => $request->get('name'),
'color_id' => $request->get('color')
));
$car->save();
$car->position_id = $car->id;
$car->save();
session()->flash('status', 'Successfully Added a Car!');
return view('cars.add');
}
public function update($id, CarFormRequest $request)
{
$car = car::whereId($id)->firstOrFail();
$car->name = $request->get('name');
$car->color_id = $request->get('color');
if($request->get('status') != null) {
$car->status = 0;
} else {
$car->status = 1;
}
$car->save();
return redirect(action('CarController#edit', $car->id))->with('status', 'The ticket '.$id.' has been updated!');
}
my routes:
Route::get('/', 'PagesController#home');
Route::get('/about', 'PagesController#about');
Route::get('/contact', 'PagesController#contact');
Route::get('/cars', 'CarsController#index');
Route::get('/cars/edit/{id?}', 'CarsController#edit');
Route::post('/cars/edit/{id?}', 'CarsController#update');
Route::get('/cars/add', 'CarsController#add');
Route::post('/cars/add', 'CarsController#store');
here is my view:
<div class="container col-md-8 col-md-offset-2">
<div class="well well bs-component">
<form class="form-horizontal" method="post">
<input type="hidden" name="_token" value="{!! csrf_token() !!}">
<input type="text" id="color_id" name="color_id" value="{!! $car->color_id !!}">
<fieldset>
<legend>Edit Car Information</legend>
<div class="form-group">
<label for="title" class="col-lg-2 control-label">Car Name</label>
<div class="col-lg-10">
<input type="text" value="{{ $car->name }}" class="form-control" id="name" placeholder="Car Name">
</div>
</div>
<div class="form-group">
<label for="title" class="col-lg-2 control-label">Car Color</label>
<div class="col-lg-10">
<div class="btn-group" data-toggle="buttons">
<label id="opt1" class="btn btn-primary">
<input type="radio" name="color" id="option1" autocomplete="off"> Red
</label>
<label id="opt2" class="btn btn-primary">
<input type="radio" name="color" id="option2" autocomplete="off"> Blue
</label>
<label id="opt3" class="btn btn-primary">
<input type="radio" name="color" id="option3" autocomplete="off"> Yellow
</label>
<label id="opt4" class="btn btn-primary">
<input type="radio" name="color" id="option4" autocomplete="off"> Green
</label>
<label id="opt5" class="btn btn-primary">
<input type="radio" name="color" id="option5" autocomplete="off"> Black
</label>
<label id="opt6" class="btn btn-primary">
<input type="radio" name="color" id="option6" autocomplete="off"> White
</label>
</div>
</div>
</div>
<div class="form-group">
<div class="col-lg-10 col-lg-offset-2">
<button class="btn btn-default">Cancel</button>
<button type="submit" class="btn btn-primary">Submit</button>
</div>
</div>
</fieldset>
</form>
</div>
</div>

Answer 1

The $id variable in whereIn must be array and you need to specify the database column too. This should be like -
public function edit($id)
{
$car = Cars::whereId('id', [$id])->firstOrFail();
return view('cars.edit', compact('car'));
}
Change all occurrence of
$car = car::whereId($id)->firstOrFail();