Brake warning light stays on

[85burb]

So sometimes my break warning light stays on. If i push my park break down the light is much brigther. So i got under dash and inspected the park break switch. It seems to be working fine. So i unpulged my proportioning valve on the front cross member and the light went out. I hooked a jumper wire from the wire that plugs in to the proportioning valve and groung and the light came back on. I put my volt meter on the valve and i showed 140 ohms or resistance from plug on valve to ground. My breaks are not leaking and it stops great. It all started when i washed my engine bay a few weeks ago. Sounds like the senser on the valve is bad or whatever. I have looked for the valve on autozone, oreillys, lmc and cant seem to find one. Are they still made or am i looking at this wrong?