No Start | U1000 CAN Communication Circuit
🚗 2006 Nissan Frontier
- Customer bought a car with a broken ignition switch (by thieves).
- He replaced the ignition switch with a key, but car didn’t start. Multiple other modules have been replaced since then to rectify the issue.
- Customer managed to start the car by hot wiring a starter relay circuit. At this point he brought it to me.
- Scanned the vehicle
- Scanner retrieved “U1000 CAN Communication Circuit” codes from most of the modules that communicated.
- Some modules didn’t communicate.
- Checked the voltages on OBDII plug pins 6 and 14 with a multimeter.
- Found suspiciously high delta V on both the CAN-Low and CAN-High (1V to 4V).
- Pulled out an oscilloscope to look a little deeper into CAN Bus activity
- Started unplugging control modules to see if i can narrow down my search of a failed component.
- Testing continuity of CAN wires revealed one line open (pink wire).
- Tracing the wire found a spot were something like a grinder cut into a wiring harness and cut some wires.
- Connected the wires back together. Car started right up. No codes.
- Scanned the CAN lines again for comparison.