DTC P173A (2018 2019)

DTC P173A:  Transmission Fluid Pressure Sensor Performance High

General Description 

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

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

Shift solenoid valve A is installed on the transmission housing. It is controlled by the ON/OFF signal from the powertrain control module (PCM) to apply line pressure to shift valve A. The signal from the PCM is output so that the line pressure is supplied to the clutch piston under the condition that overdrive clutch engagement is requested during running at 44 mph (70 km/h) or more. When the signal to shift solenoid valve A from the PCM is ON, and the line pressure is applied to shift valve A, it operates against the shift valve A spring. When the signal to shift solenoid valve A from the PCM is OFF, and the line pressure is discharged, shift valve A is inactive. The PCM monitors the transmission fluid pressure sensor. If the transmission fluid pressure sensor pressure is a specified value or more when the engine is stopped or engagement of the over drive clutch is not requested, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type 

Execution	Continuous
Sequence	None
Duration	3.0 seconds or more
DTC Type	One drive cycle, MIL off, shift position indicator blinks

Enable Conditions 

Condition
12 volt battery voltage [BATTERY VOLTAGE]		11 V

[ ]: HDS Parameter

Malfunction Threshold 

The transmission fluid pressure sensor value is 177 kPa (1327 mmHg, 52.3 inHg) or more for at least 3.0 seconds when the engine is stopped or engagement of the over drive clutch is not requested.

Possible Cause 

Confirmation Procedure 

Operating Condition 

1. Enter the maintenance mode, then start the engine. Hold the engine speed [ENGINE SPEED] at 3, 000 RPM without load (in P or N) until the radiator fan comes on, then let it idle.
2. Drive the vehicle at speed of 44 mph (70 km/h) or less for at least 10 seconds.

• Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.

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.