Multi-code OBD2 diagnosis
Enter all the codes your scanner showed, not just the first one. We give you the overall severity, whether you can keep driving, the order in which to check them and how they relate to each other.
Summary
- Overall severity
- Critical
- Can I keep driving?
- No, stop and have it checked
- Estimated cost
- $50 to $1,200
- Codes analyzed
- 1 of 1
The order below is the recommended one: first the codes that can cause the others. After each repair, clear the codes and check which ones come back.
Order of inspection
U0100 Lost Communication With ECM/PCM A Critical
The U0100 code means one or more modules in the vehicle stopped receiving messages from the engine computer over the data bus. Almost always the problem is not the computer itself but its power supply, its ground or the network wiring. It is a serious code: the vehicle may not start or may stall while driving, so do not drive it until it is checked.