HYBRID CONTROL SYSTEM, Diagnostic DTC:P0851-579, P0852-580
| DTC Code | DTC Name |
|---|---|
| P0851-579 | Park / Neutral Switch Input Circuit Low |
| P0852-580 | Park / Neutral Switch Input Circuit High |
DESCRIPTION
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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 above the shift lever. The switch is a momentary type, in which the button does not lock mechanically.
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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 |
|
| P0852 | 580 | Open or +B short in P position switch circuit |
CAUTION / NOTICE / HINT
Tech Tips
After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.
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Turn the power switch on (IG) and wait for 5 seconds or more.
PROCEDURE
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INSPECT P POSITION SWITCH (TRANSMISSION SHIFT MAIN SWITCH)
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Disconnect the L124 P position switch (transmission shift main switch) connector.
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Text in Illustration *a Component without harness connected
(P Position Switch (Transmission Shift Main Switch))
Measure the resistance according to the value(s) in the table below.
Standard Resistance Tester Connection Condition Specified Condition L124-4 (S) - L124-2 (E) Switch pressed 680 Ω L124-4 (S) - L124-2 (E) Switch released 4580 Ω Tech Tips
Terminals No. 1 and No. 8 on the component side connector are empty.
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Reconnect the L124 P position switch (transmission shift main switch) connector.
NG 
REPLACE P POSITION SWITCH (TRANSMISSION SHIFT MAIN SWITCH)
OK 
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CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - P POSITION SWITCH (TRANSMISSION SHIFT MAIN SWITCH))
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Disconnect the L5 hybrid vehicle control ECU connector.
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Disconnect the L124 P position switch (transmission shift main switch) connector.
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Text in Illustration *a Rear view of wire harness connector
(to Hybrid Vehicle Control ECU)
*b Front view of wire harness connector
(to P Position Switch (Transmission Shift Main Switch))
Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open) Tester Connection Condition Specified Condition L5-16 (P1) - L124-4 (S) Power switch off Below 1 Ω Standard Resistance (Check for Short) Tester Connection Condition Specified Condition L5-16 (P1) or L124-4 (S) - Body ground and other terminals Power switch off 10 kΩ or higher Tech Tips
As necessary, check that there is no short to power supply wires when performing the above wire harness inspection.
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Reconnect the L124 P position switch (transmission shift main switch) connector.
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Reconnect the L5 hybrid vehicle control ECU connector.
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
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CHECK HARNESS AND CONNECTOR (P POSITION SWITCH (TRANSMISSION SHIFT MAIN SWITCH) - BODY GROUND)
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Disconnect the L124 P position switch (transmission shift main switch) connector.
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Text in Illustration *a Front view of wire harness connector
(to P Position Switch (Transmission Shift Main Switch))
Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open) Tester Connection Condition Specified Condition L124-2 (E) - Body ground Power switch off Below 1 Ω -
Reconnect the L124 P position switch (transmission shift main switch) connector.
OK
REPLACE HYBRID VEHICLE CONTROL ECU Click here
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
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