Used ECU Compatibility
A used ECU can work, but only if the part number, VIN, immobilizer pairing, and programming all match the car you are putting that module into.
No Start After Jump
A no-start after a jump can come from a voltage spike that damaged the PCM or TIPM, not just a battery that still needs a charge or a new fuse.
P0685 Code Meaning
A P0685 code means the ECM or PCM power relay control circuit has a fault, often from the ASD or main relay, a fuse, wiring, or the module itself.
Scan Tool No Communication
When a scan tool has no communication with the ECU, check DLC power, CAN wiring, and ignition first. That blank screen is not the same as a U0100 code.
P0606 Code Meaning
A P0606 code points to a PCM or ECM processor fault, but low voltage, bad grounds, and a failed flash can look just like a bad module before you replace it.