DTC U0100: Lost Communication with ECM / PCM "A": Procedure

1. Connect a Techstream to the DLC3.
2. Turn the ignition switch on and turn the tester on.
3. Check for DTCs and note any codes that are output. Refer to DATA LIST / ACTIVE TEST .
4. Clear the DTC. Refer to DTC CHECK / CLEAR .
5. Recheck for DTC. Refer to DTC CHECK / CLEAR .

   Result

   Result	Refer to
   DTC output	A
   DTC not output	B

B → Refer to step   3 

A → Refer to step   2