DTC P0851-579: Park / Neutral Switch Input Circuit Low; DTC P0852-580: Park / Neutral Switch Input Circuit High: Description

Instead of having a parking position as one of the positions of the conventional shift lever, a P position switch (transmission shift main switch) is provided independently below the shift lever. The switch is a momentary type, in which the button does not lock mechanically.
The P position switch (transmission shift main switch) contains resistors R1 and R2. When the P position switch (transmission shift main switch) is not pressed, the switch provides a combined resistance of R1 and R2; and when the P position switch (transmission shift main switch) is pressed, the switch provides only the resistance of R1. The voltage at the P1 terminal of the hybrid vehicle control ECU varies with the changes in the resistance of the switch. The hybrid vehicle control ECU determines the P position switch (transmission shift main switch) operation according to this resistance signal.

DTC No.	INF Code	DTC Detection Condition	Trouble Area
P0851	579	GND short in P position switch circuit	P position switch (Transmission shift main switch) Wire harness or connector Hybrid vehicle control ECU
P0852	580	Open or +B short in P position switch circuit