The SG4 wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM, then recheck. If DTC P2123 goes away and the PCM was substituted, replace the original PCM.?
NO
Repair an open in the SG4 wire between PCM connector No. 2 terminal No. 10 and the APP sensor.?