DTC P0871

BHE050201026W26

DTC P0871

Oil pressure switch F circuit malfunction

DETECTION CONDITION

• When driving, hydraulic pressure should be generated in the low and reverse brake, but oil pressure switch F does not turn on.
• When driving, hydraulic pressure should not be generated in the low and reverse brake, but oil pressure switch F does not turn off.

Diagnostic support note:

• This is continuous monitor (CCM).
• AT warning light illuminates if TCM detects the above malfunction conditions in two consecutive drive cycles.
• PENDING CODE is available.
• FREEZE FRAME DATA is available.
• MIL does not illuminate.
• DTC is stored in TCM memory.

POSSIBLE CAUSE

• Oil pressure switch F malfunction
• Open circuit in wiring harness between oil pressure switch F terminal A and TCM terminal 2H
• Short to ground in wiring harness between oil pressure switch F terminal A and TCM terminal 2H
• Damaged connector between oil pressure switch F and TCM
• TCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1

VERIFY FREEZE FRAME DATA HAS BEEN RECORDED

• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2

VERIFY RELATED REPAIR INFORMATION AVAILABILITY

• Verify related Service Bulletins and/or on-line repair information availability.
• Is any related repair information available?
Yes
Perform repair or diagnosis according to the available repair information.
• If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3

INSPECT FOR DTC

• Turn the ignition switch to the ON position (engine off).
• Inspect for DTCs.
• Are any other DTCs output?
Yes
Follow the applicable DTC inspection procedure.
No
Go to the next step.
4

INSPECT AT SOLENOID VALVE CONNECTOR FOR POOR CONNECTION

• Turn the ignition switch to the LOCK position.
• Disconnect the AT solenoid valve connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Are the connector and terminals normal?
Yes
Go to the next step.
No
Repair or replace the connector and/or terminal, then go to Step 15.
5

INSPECT TCM CONNECTOR FOR POOR CONNECTION

• Disconnect the TCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Are the connector and terminals normal?
Yes
Go to the next step.
No
Repair or replace the connector and/or terminal, then go to Step 15.
6

INSPECT TCM CIRCUIT FOR OPEN CIRCUIT

• Inspect for continuity between the TCM (wiring harness-side) terminal 2H and AT solenoid valve connector (wiring harness-side) terminal L.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 15.
7

INSPECT TCM CIRCUIT FOR SHORT TO GROUND

• Inspect for continuity between the TCM (wiring harness-side) terminal 2H and body ground.
• Is there continuity?
Yes
Repair or replace the wiring harness, then go to Step 15.
No
Go to the next step.
8

INSPECT CONTROL VALVE BODY CONNECTOR FOR POOR CONNECTION

• Disconnect the control valve body connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Are the connector and terminals normal?
Yes
Go to the next step.
No
Repair or replace the connector and/or terminal, then go to Step 15.
9

INSPECT AT SOLENOID VALVE CONNECTOR CIRCUIT FOR OPEN CIRCUIT

• Inspect for continuity between the AT solenoid valve connector (transmission case side) terminal L and control valve body (wiring harness-side) terminal B.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 15.
10

INSPECT TCM CIRCUIT FOR SHORT TO GROUND

• Inspect for continuity between the AT solenoid valve connector (transmission case-side) terminal L and body ground.
• Is there continuity?
Yes
Repair or replace the wiring harness, then go to Step 15.
No
Go to the next step.
11

INSPECT OIL PRESSURE SWITCH F CONNECTOR FOR POOR CONNECTION

• Disconnect the oil pressure switch F connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Are the connector and terminals normal?
Yes
Go to the next step.
No
Repair or replace the connector and/or terminal, then go to Step 15.
12

INSPECT CONTROL VALVE BODY CIRCUIT FOR OPEN CIRCUIT

• Inspect for continuity between the control valve body connector terminal B (part-side) and oil pressure switch F (wiring harness-side) terminal A.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 15.
13

INSPECT CONTROL VALVE BODY CIRCUIT FOR SHORT TO GROUND

• Inspect for continuity between the control valve body connector (wiring harness-side) terminal L and body ground.
• Is there continuity?
Yes
Repair or replace the wiring harness, then go to Step 15.
No
Go to the next step.
14

INSPECT OIL PRESSURE SWITCH F

• Inspect oil pressure switch F.
• Is the oil pressure switch F normal?
Yes
Go to the next step.
No
Replace the oil pressure switch F, then go to the next step.
15

VERIFY TROUBLESHOOTING OF DTC P0871 COMPLETED

• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the TCM memory using the WDS or equivalent.
• Drive the vehicle and make sure that the gears shift smoothly from 1GR to 4GR.
• Is the same DTC present?
Yes
Replace the TCM, then go to the next step.
No
Go to the next step.
16

VERIFY AFTER REPAIR PROCEDURE

• Perform the "After Repair Procedure".
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.