Transmission codes P1781 and P1784?

SACFOX189

MEMBER
1999 CHRYSLER 300M
3.5L
V6
2WD
AUTOMATIC
200,000 MILES

I installed shift solenoid pack put it back together and put the same fluid. Test run. Then put back on OBD P1781 was the result.

Friday, October 14th, 2022 AT 4:15 PM

2 Replies

JACOBANDNICKOLAS

MECHANIC
109,644 POSTS

Hi,

The code is specific to the OD pressure switch sensor circuit. What that means is the pressure switch is open or closed at the wrong time in a given gear or shift.

There are multiple things that can cause this code to set (see the last pic below). Most commonly, it is the pressure switch itself. However, the only way to confirm is to perform the diagnostics related to the code.

I attached the diagnostics below for your review. Take a look through them and let me know if it is something you feel comfortable doing.

Take care

Joe

See pics below.

Images (Click to make bigger)