DTC 45: No Communication With Left Rear Door Control Unit (LCU04)

Check Power Supply To LCU04

Check for poor connection at LCU04. Repair as necessary. Disconnect LCU04 harness connector. Turn ignition on. Using a DVOM, measure voltage between terminal No. 15 at LCU04 harness connector and ground. See Figure . If battery voltage is present, go to next step. If battery voltage is not present, repair open in power supply circuit (Yellow/Black wire) between fusible link and LCU04 harness connector. See WIRING DIAGRAMS .

Check Ground Circuit To LCU04

Check for poor connection at LCU04. Repair as necessary. Disconnect LCU04 harness connector. Using a DVOM, check for continuity between ground and terminal No. 14 at LCU04 harness connector. If continuity is present, go to next step. If continuity is not present, repair open in ground circuit (Black wire). See WIRING DIAGRAMS .

Check For Open Data Circuit

Using a DVOM, check for continuity between terminal No. 3 at LCU04 harness connector and terminal No. 61 at BCM harness connector. See Figure . If continuity is not present, repair open in data circuit (Red/Yellow wire or Red/Black wire) between BCM and LCU04. If continuity is present, erase DTCs and recheck for DTCs. If DTC 45 is retrieved again, replace LCU04.