The diagnosis U1157 Code lets you know the problem of the car engine. For solving the car engine problem, it is necessary to know the real meaning of the code. The real meaning is called manufacturer’s meaning. The automobile meaning of the code is found in different sites and the automobile meaning of the U1157 Code is U for Network Code Problem is climate control system, lighting, airbags, etc. 1 for MFG – Manufacturer Specific. 1 for Transmission. 5 for TP Sensor Learn Not Complete and 7 for Cruise Inhibit Control Circuit. The U1157 engine code is a kind of network problem and it is necessary to fix the car engine.