Unity crashes when trying to run depth shader with color lerp.

I'm building a little custom shader that uses the z-depth value as T for a color lerp. So the result should be that instead of a black and white depth view. I can have the colors be red and green (for example).

 Properties {
         _minColor ("Min Black", Float) = 0.0
         _maxColor ("Max Black", Float) = 1.0
         _Color1 ("Some Color", Color) = (0,0,0,1)
         _Color2 ("Some Color", Color) = (1,1,1,1)
     }
 
 SubShader {
 Tags { "RenderType"="Opaque" }
 
 Pass{
 CGPROGRAM
 #pragma vertex vert
 #pragma fragment frag
 #include "UnityCG.cginc"
 
 sampler2D_float _CameraDepthTexture;
 fixed _minColor;
 fixed _maxColor;
 float4 _Color1;
 float4 _Color2;
 
 struct v2f {
    float4 pos : SV_POSITION;
    float4 scrPos:TEXCOORD1;
 };
 
 //Vertex Shader
 v2f vert (appdata_base v){
    v2f o;
    o.pos = UnityObjectToClipPos (v.vertex);
    o.scrPos=ComputeScreenPos(o.pos);
    return o;
 }
 
 //Fragment Shader
 half4 frag (v2f i) : COLOR{
    float depthValue = Linear01Depth (tex2Dproj(_CameraDepthTexture, UNITY_PROJ_COORD(i.scrPos)).r);
    //depthValue = clamp(depthValue,_minColor,_maxColor);
    half4 depth;
 
    //depth.r = depthValue;
    //depth.g = depthValue;
    //depth.b = depthValue;
    //depth.a = 1;
 
    float4 LerpColor = lerp(_Color1, _Color2, depthValue);
 
    depth.r = LerpColor.r;
    depth.g = LerpColor.g;
    depth.b = LerpColor.b;
    depth.a = 1;
 
    return depth;
 }
 ENDCG
 }
 }
 FallBack "Diffuse"
 }

The main part is taken from this tutorial When I open the editor the game view shows the result I'm after, but when I run it. Unity crashes immediately. When am I missing?

Thanks!