I'm having an oddball 4wd indicator light issue... 89 4runner, manual hubs/trans/tcase. Truck originally had an auto trans.

When I put the truck in 4wd, it cuts out at 2k rpm. I have not checked to see whether it's fuel cut or spark. It's repeatable and isolatable. I did cut and splice some stuff on the wiring harness (trans/tcase connectors) doing the swap.

If I unplug the 4wd sensor, it is fine. If I'm in 2wd, it's fine. basically it is directly tied to whether the 4wd indicator light is on in the dash. I did the swap about a year ago, and it's been fine up until now. It started happening when we got a wet snow, but if it was cold/dry and slick, I could use 4wd without issue. Now it's all the time.

I am not 100% certain I've got the correct 2 wires for the indicator light. Is there a wire in the harness down there that would engage a 2000 rpm rev limiter? I thought the indicator light was a pretty direct simple circuit that didn't talk to anything else in the truck. Am I wrong on that?

Thanks in advance!
Eric