Theory Of Operation
WARNING: This page is about a different car, the 2015 Jeep Renegade. However, it is still accessible from the selected car via links, so may be relevant.
This diagnostic checks the status of the SPI communication between the Main Micro Processor (MMP) and three separate integrated circuits named MGS1, MGS2 and MGS3. The MGS1 drives the even clutch electrovalve (PPV-K2) and the 2-3-R gear-engaging electrovalve (PPV1). The MGS2 drives the odd clutch electrovalve (QPV-K1) and the 1-4-5-6 gear-engaging electrovalve (PPV2). The MGS3 drives the gate select electrovalve (PPVS). The MMP communicates with each MGS via a SPI protocol which is checked by an internal diagnostic of the MGS. When each MGS detects a communication malfunction, the DTC is set.