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
- High
- Can I keep driving?
- Yes, but with caution
- Estimated cost
- $20 to $400
- 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
P0642 Sensor Reference Voltage "A" Circuit Low High
The P0642 code means there is a fault in the 5 volt reference A voltage the computer sends to a group of sensors. It often sets several sensor codes at once and puts the vehicle in limp mode. The typical cause is a sensor or wire in the group shorted to ground.