الدرع الحراري أو العازل لم يُعَد تركيبه

A heat shield or thermal interface pad left off after work, so a component runs hotter than designed. It is a repair-induced fault, and its timing is what identifies it: heat-related codes that begin shortly after work in the area.

A thermal pad is a conductor, not padding. It carries heat from a module's power stage into its housing or heatsink, and a module reassembled without it — or with the old one reused after it has been compressed and dried — runs far hotter than it should. The module then derates or reports internal temperature, and the fault looks like a failing module.

Heat shields work the other way, keeping exhaust radiation off a sensor, a harness or a fuel line. Missing, they cook whatever they protected, so the resulting fault appears in a component the missing shield never touched. Check what was recently removed in the area and compare the installation against the diagram — these parts look optional on reassembly and are not.