FixVault

DTC Advanced Diagnostics: P0766

DTC P0766  : Shift Solenoid Valve D Stuck OFF

General Description 

GHH477515Courtesy of HONDA, U.S.A., INC.

Shift solenoid valve D is installed on the valve body assembly. It is controlled by the ON/OFF signal from the transmission control module (TCM) to apply line pressure to the B1 cut valve. The B1 cut valve does not operate when shift solenoid valve D is OFF, and operates when it is ON. Transmission fluid pressure switch A is installed on the hydraulic passage where transmission fluid pressure switch A outputs ON when the B1 cut valve is not operating. Since the B1 cut valve does not operate when shift solenoid valve D is OFF, the hydraulic pressure is output from the B1 cut valve and turns transmission fluid pressure switch A to ON. Contrary, the B1 cut valve operates when shift solenoid D is ON, the hydraulic pressure is cut off from the B1 cut valve and turns transmission fluid pressure switch A to OFF. For detecting the malfunction, the TCM uses the values of transmission fluid pressure switch A and transmission fluid pressure sensor E when the B1 cut valve is operated. If transmission fluid pressure switch A is ON and the value of transmission fluid pressure sensor E is in abnormal range for a specified time when the B1 cut valve is operated, the TCM detects a shift solenoid valve D stuck off failure and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type 

Execution Continuous
Sequence None
Duration 1.5 seconds or more
DTC Type Two drive cycles, MIL on, shift position indicator blinks

Enable Conditions 

Condition Minimum Maximum
Engine speed [Engine Speed] 500 rpm -
12 volt battery voltage [Battery Voltage] 10 V -
Control command to shift solenoid valve D ON
Other Value of transmission fluid pressure sensors A, B, C, D, and F are 300 kPa (3.06 kgf/cm 2, 43.5 psi) or less

[ ]: HDS Parameter

Malfunction Threshold 

Transmission fluid pressure switch A is ON and the value of transmission fluid pressure sensor E is more than 200 kPa (2.0 kgf/cm 2, 29.0 psi) for at least 1.5 seconds when the B1 cut valve is operated.

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 

Start the engine, and wait for several seconds in P position/mode.

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 MIL comes on, the shift position indicator blinks, and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC 

The shift position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool clear command.