Transmission issue - P0847

Been a while, life seems to be going at warp speed over the last year! Anyway the Accord has been fine, until this week:

Decided on a short break in S.Wales and all was good until a check transmission warning came on and the green D started flashing . Anyway, turned off and left for a while, the light and message hasn't returned but it's not performing like it should in the lower gears. Not had chance to check the fluid but it's only 5k old, ran a scan and got P0847 Switch B low voltage (my first even code I've got on a Honda!). The manual says this is caused by an electrical fault and not mechanical transmission failure. Think I might have to leave this one to a local garage.

After looking at the manual it seems like a simple swap, don't think I'll have time though..

What causes the P0847 code?
A handful of different issues can cause the P0847 code to be triggered, including:

• Defective electronic pressure control solenoid
• Defective transmission fluid pressure sensor
• Malfunctioning electronic pressure regulator
• Insufficient transmission fluid levels
• Dirty transmission fluid
• Mechanical issues within the internal transmission
• Hydraulic blockages in the fluid passages of the internal transmission
• Defective hydraulic pump
• Malfunctioning PCM
• Malfunctioning transmission control module

What are the symptoms of the P0847 code?
The P0847 trouble code will often be accompanied by the check engine soon Warning Light illuminating on the vehicle’s instrument panel. The car may also experience severe transmission problems, such as slippage, harsh shifting, overheating, and even a total inability to shift. The PCM may also put the transmission in “limp-in” mode. Furthermore, the torque converter clutch may fail to work, and the vehicle is likely to experience a decrease in fuel efficiency.

This is from the Honda Accord workshop manual:

DTC P0847:
Short in 3rd Clutch Transmission Fluid Pressure Switch Circuit, or 3rd Clutch Transmission Fluid Pressure Switch Stuck ON
NOTE:
Record all freeze data and review General Troubleshooting Information before you troubleshoot.
This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

Tempted to do both switches (2 & 3), will see how much they are on Monday.