How to reset AHC pump or bleed air from the system?

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I have been struggling to find out why the AHC is not working on my 2000 LX470 (190K). It is relatively new to me having been owned by my BIL in Phoenix (no rust) and well maintained at dealer. I have read through the AHC threads and tested and eliminated problems with relays (in engine and under dash), all 6 fuses, switches, pump. The issue is that the lights flash to go up or down but nothing ever happens. The pump never runs. I connected E1 and Ts pins and got the flashing lights but raising and lowering did nothing. Pump runs when I connect to power.

I got TechStream working. A challenge by itself but I was able to see readings as below. I could not find anything on bad AHC ECU in the posts but am beginning to suspect that could be the issue. What would you gurus recommend next?View attachment 3809336
I got it working. Replaced the ECU with a used one off eBay. Now to adjust based on info in this forum.
 

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