Can anyone tell me what IG1 is in this diagram on TIS? It isn't a body wiring harness listed in the "Location and Routing" or a connector/junction listed in the "Connector List"

I have ohmed out all the wired between the stereo head unit and the amp and betweeen the amp and the speakers. I have found that there are open wires between the amp and the Front left Squawk/Tweet and the amp to the front left woofer. There is a poor connection bewteen the amp and the rear door speaker. I am trying to locate the failed wires since there are multiple failures on one harness and I don't want to just run new wire if I'm looking at one failed connector or damage to an entire harness. Next step is removing both rear seats and carpet to unwrap the harness leaving the amp; but I'm hoping someone might be able to shed a little light on IG1.

Seaching all of TIS, IG1 only refers to a relay for engine starting, which has nothing to do with this part of the wiring harness.


What is IG1?!


EDIT:
I have learned in TIS to click the IG1 "box" on the graphic display and then click the red box at the bottom right corner (that looks like an sms messaging icon) to show the connector. IG1 is known as "Instrument Panel No.2 Wire and Floor Wire (Instrument Panel Brace LH) Code IG1" and it leaves the amp travelling forward, just left on the center hump and disappears under the front seat center console.... I think they may have left a connector loose when they replaced the dash in this car, so planning to work my way until I find the fault. If a connector isn't loose in IG1, then 4 wires have failed separately which seems unlikely.

 

Just in case this ever helps anyone, I found a connector that was disconnected near the drivers ankle under the gear shifter (2007 RX350). Only 4 wires in the connector, all speaker wires. I don't know if it was the air conditioner mechanic who replaced the A/C evaporator or the Lexus dealership who replaced the dashboard who disconnected it. But it must have been inserted but not locked because the speakers stopped working many months after either service.

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