LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Acura >> 2021 >> TLX Base >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Automatic Transaxle - Advanced Diagnostics >> Advanced Diagnostics >> DTC Advanced Diagnostics: P084D
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC Advanced Diagnostics: P084D

DTC P084D  : Transmission Fluid Pressure Switch B Circuit High

General Description 

GHH477561Courtesy of HONDA, U.S.A., INC.
GHH477562Courtesy of HONDA, U.S.A., INC.

Transmission fluid pressure switch B is installed on the hydraulic pressure output passage of shift solenoid valve A. When shift solenoid valve A outputs a hydraulic pressure, transmission fluid pressure switch B is ON, and OFF when there is no hydraulic pressure. The two-way clutch is operated by driving the two-way clutch actuator valve with shift solenoid valves A, B, and D and clutch pressure control solenoid valve B. The two-way clutch actuator valve stroke sensor which measures the stroke position of the two-way clutch actuator valve is structured by two systems as the sensor characteristics are shown as in the figure. When the stroke value of the two-way clutch actuator valve stroke sensor is approximately 4.7 mm (0.19 in) or more, the two-way clutch is in reverse position, and when it is approximately -4.8 mm (-0.19 in) or less, it is in forward position. For detecting the malfunction, the TCM uses the values of the two-way clutch actuator valve stroke sensor and transmission fluid pressure switch B when the two-way clutch is switch controlled to the reverse position. If transmission fluid pressure switch B is ON and the two-way clutch actuator valve stroke sensor value is in abnormal range for a specified time when the two-way clutch is switch controlled to the reverse position, the TCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type 

Execution Continuous
Sequence None
Duration 1.2 seconds or more
DTC Type Two drive cycles, MIL off, shift position indicator blinks

Enable Conditions 

Condition Minimum Maximum
Engine speed [Engine Speed] 500 rpm -
12 volt battery voltage [Battery Voltage] 10 V -
Clutch C3 command pressure 1, 050 kPa (10.7 kgf/cm 2, 152.3 psi) -
Control command to shift solenoid valve A OFF
Control command to shift solenoid valve B ON
Control command to shift solenoid valve D OFF
Other Two-way clutch is in forward position when two-way clutch is started to switch control to reverse position (two-way clutch actuator valve stroke sensor value is -4.8 mm (-0.19 in) or less)

[ ]: HDS Parameter

Malfunction Threshold 

Transmission fluid pressure switch B is ON and the two-way clutch actuator valve stroke sensor value is less than 0 mm (0 in) for at least 1.2 seconds when the two-way clutch is switch controlled to the reverse position.

Possible Cause 

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Confirmation Procedure 

Operating Condition 

Diagnosis Details 

Conditions for setting the DTC 

When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the TCM memory. If the malfunction returns in the next (second) drive cycle, the shift position indicator blinks and a Confirmed DTC and the freeze data are stored. The MIL does not come on.

Conditions for clearing the DTC 

The shift position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool clear command.