P0852: Park/Neutral Switch Input Circuit High
What to do
The engine may not crank at all. Before assuming the starter has failed, note that this switch can prevent cranking entirely while everything in the starting system is perfectly healthy — moving the selector to neutral and trying again sometimes works as a temporary measure.
What this code means
The park/neutral signal reads above its valid range — an open circuit or a short to supply. This is the safe failure direction: the module never sees park or neutral confirmed, so the starter is inhibited and the engine will not crank at all.
Inconvenient, occasionally stranding, and considerably preferable to P0851. A vehicle that has suddenly refused to crank while the battery, starter and lights are all plainly healthy is a good candidate for this rather than anything electrical in the starting system.
Likely causes
Start here
- Open circuit in switch wiring · moderate
- Faulty park neutral switch · moderate
- Corroded or loose connector · easy
Less common
- Misadjusted transmission range sensor · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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