2 Year Problem.

[RedLexusSC400]

Okay, so I'm coming up on 2 years with this problem. I've had a handful of mechanics look at it. And I've posted on here with no luck. But I am now one step closer.

2 years ago my heater just started to not come on every once in a while. When it did it worked great. It always blows air. Now what's weird is even when it wasn't blowing any hot air at all, and I had mechanics look at it, everything in the engine bay worked great, all the way back to the heater core. Even had Lexus certified mechanics looking at it. But it was so off and on. Over time it started to work less and less until it never came on in the last few months. But I had the car in a friends shop to replace the door hinge (which was a another nightmare), and he had to disconnect some crappy wire job. He assumed it was my sound system or after market alarm or remote start. He reconnected it and since that day my heater has worked great!... When it's 80 degrees to HOT. One click below 80 it doesn't blow warm air at all.

Now I'm not sure it had anything to do with the wiring, but I havn't done anything else. And if it was the wires, how could it be so off and on, and work less and less. And why does it not work under 80?

I don't know if I am going to get anything further with this, I am extremely happy it works (My girlfriend even more), and I am worried I'll go back out there one of these days and it won't. Curious though if it gives you guys any more ideas what it could be.

Thanks for any info. And sorry about the novel.