I have error P1560 The description is below. I've opened all connectors and sprayed CRC 2-26 (cleaner). Doesn't help. Also checked every single fuse both in the engine box and the box next to the steering wheel. Note that I've just changed the glow plugs. I'm afraid I may have pulled too hard on some of the wiring but I haven't noticed any damage. Other than that I'm planning to test all the relays. I'm reading about measuring tension on circuits but I don't know what it means / how to do it. P1560 Definition: Back-up Voltage Circuit Malfunction Description: Battery voltage ≥ 10.9 V. Engine condition - After engine starting. Low voltage condition of back-up power supply. Cause: Wiring harness between ECM and ground chassis needs repair. Poor contact of the ECM connector. Defective fuse. Wiring harness between ECM and negative battery terminal needs repair.