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 $250
- 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
P0851 Park/Neutral Switch Input Circuit Low High
The P0851 code means the signal from the park/neutral position switch is lower than the computer expects. The main effect is that the engine will not start, or idles wrong when you shift into gear. A signal wire shorted to ground is the usual cause.