Hello! I'm Rixster...
I'm going to try and help you on this but I'm going to need some info first to get started.
How long has this been happening?
How many Miles?
Have there been any modification made recently?
It sounds like there is a short or intermittent ground fault in either the interpreter module (BCM) or the wiring to it.
It is possible there may be a pinched wire in the harness for the indicator down by the trans. that may have happened at trans. install.
To properly diagnose this problem you may need a "Tech II" Scan tool or basically take it to the dealership. If the Range switch is not the problem the switch interpreter is and it is logical it would cause all the other symtoms if it is the BCM (Body Control Module)
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