the engine control temp sensor. You have 2 sensors on the water pipe on the front of the engine that are clearly visible and accessable. The one with a single wire goes directly to your gauge cluster to show you the water temp. The larger connector with 2 wires is the engine control temp sensor, and they're notorious for developing corrision on the contacts. Remove the connector and clean off all the green corrosion that I guarantee you is there, use some dielectric grease on the contacts before reconnecting and that should fix your problem.
I highly doubt it has any relevance to your jwt chip.
Cheers, JBrobst
"A life spent making mistakes is not only more honorable, but more useful than a life spent doing nothing." George Bernard Shaw
