DTC P0852 Neutral Switch Input Circuit High (At Model)

DTC DETECTING CONDITION:

Two consecutive driving cycles with fault
GENERAL DESCRIPTION < Ref. to DTC P0852 NEUTRAL SWITCH INPUT CIRCUIT HIGH (AT MODEL) , Diagnostic Trouble Code (DTC) Detecting Criteria. >

TROUBLE SYMPTOM:

Erroneous idling

CAUTION: After repair or replacement of faulty parts, conduct Clear Memory Mode < Ref. to , OPERATION , Clear Memory Mode.> and Inspection Mode < Ref. to , PROCEDURE , Inspection Mode.>.

WIRING DIAGRAM:

Fig 1: DTC P0852 Neutral Switch Input Circuit High (AT Model)

Courtesy of SUBARU OF AMERICA, INC.

DTC P0852 NEUTRAL SWITCH INPUT CIRCUIT HIGH (AT MODEL) DIAGNOSIS

Step	Check	Yes	No
1. CHECK FOR ANY OTHER DTC ON DISPLAY .	Is any other DTC displayed?	Inspect DTC using "List of Diagnostic Trouble Code (DTC)". < Ref. to , LIST OF DIAGNOSTIC TROUBLE CODE (DTC) . >	Go to step 2.
2. CHECK INPUT SIGNAL FOR ECM. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground in select lever "N" and "P" ranges. Connector & terminal (B137) No. 9 (+) - Chassis ground (-):	Is the voltage less than 1 V?	Go to step 3.	Go to step 5.
3. CHECK INPUT SIGNAL FOR ECM. Measure the voltage between ECM and chassis ground in select lever except for "N" and "P" ranges. Connector & terminal (B137) No. 9 (+) - Chassis ground (-) :	Is the voltage more than 10 V?	Go to step 4.	Go to step 5.
4. CHECK POOR CONTACT. Check poor contact in ECM connector.	Is there poor contact in ECM connector?	Repair poor contact in ECM connector.	Contact SOA Service Center.
5. CHECK INPUT SIGNAL FOR ECM. Measure the voltage between ECM and chassis ground. Connector & terminal (B137) No. 9 (+) - Chassis ground (-):	Is the voltage more than 10 V?	Repair battery short circuit in harness between ECM and inhibitor switch connector.	Go to step 6.
6. CHECK HARNESS BETWEEN ECM AND INHIBITOR SWITCH CONNECTOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM and inhibitor switch. Measure the resistance of harness between ECM and inhibitor switch connector. Connector & terminal (B137) No. 9 - (T7) No. 7:	Is the resistance less than 1 Ω?	Go to step 7.	Repair harness and connector. NOTE: In this case, repair the following: Open circuit in harness between ECM and inhibitor switch connector Poor contact in coupling connector Poor contact in inhibitor switch connector Poor contact in ECM connector
7. CHECK INHIBITOR SWITCH GROUND LINE. Measure the resistance of harness between inhibitor switch connector and engine ground. Connector & terminal (T7) No. 12 - Engine ground:	Is the resistance less than 5 Ω?	Go to step 8.	Repair open circuit in harness between inhibitor switch connector and starter motor ground line. NOTE: In this case, repair the following: Open circuit in harness between inhibitor switch connector and starter motor ground line Poor contact in starter motor connector Poor contact in starter motor ground Starter motor
8. CHECK INHIBITOR SWITCH. Measure the resistance between inhibitor switch connector receptacle's terminals in select lever "N" and "P" ranges. Terminals No. 7-No. 12:	Is the resistance less than 1 Ω?	Go to step 9.	Replace the inhibitor switch.< Ref. to INHIBITOR SWITCH . >
9. CHECK SELECTOR CABLE CONNECTION.	Is there any fault in selector cable connection to inhibitor switch?	Repair selector cable connection.< Ref. to INSPECTION , Select Cable. >	Contact SOA Service Center.