the thermo time switch is located at the back of the engine on the inlet manifold intermediate flange which has water going through it for thermo switch and the ecu temp sensor so you will need to drain a bit .best accessed from underneath i think.its more or less directly above the turbo oil supply pipe outlet from the block the thermo switch has its multy plug pointing to the bulkhead and the ecu sensor,s multyplug is pointing down.