DTC P0977

DTC P0977: Shift Solenoid Valve B (Open)

General Description

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

Capacity of Over Drive Clutch		Shift Solenoid Valve A
Capacity of Over Drive Clutch		ON (12 V)	OFF (0 V)
Shift Solenoid Valve B	ON (12 V)	ON	OFF
Shift Solenoid Valve B	OFF (0 V)	OFF	OFF

When shift solenoid valves A and B are turned ON, the hydraulic pressure circuit opens. The hydraulic pressure circuit supplies/discharges hydraulic pressure to/from each clutch according to the combination of the ON/OFF status of the shift solenoid valves. The powertrain control module (PCM) commands the driver circuit to turn ON the shift solenoid valve. The circuit detects malfunctions such as a circuit short or open, and sends back a return signal during the PCM's command. When the return signal does not match the PCM command to turn OFF the shift solenoid valve, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type

Execution	Continuous
Sequence	None
Duration	1 second or more
DTC Type	One drive cycle, MIL off, shift position indicator blinks

Enable Conditions

Condition	Minimum	Maximum
12 volt battery voltage [BATTERY VOLTAGE]	11 V	-

[ ]: HDS Parameter

Malfunction Threshold

The return signal does not match the command to turn OFF shift solenoid valve B for at least 1 second.

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.

Shift solenoid valve B SHB line open (includes a loose or disconnected connector)
Shift solenoid valve B internal circuit open
PCM internal failure

Confirmation Procedure

Operating Condition

Turn the vehicle to the READY TO DRIVE mode.
Shift the transmission to P position/mode, and wait for at least 1 second.

With the HDS

None.

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected, the shift position indicator blinks and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory. 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 or by disconnecting the 12 volt battery.