Code p1784 appeared and would like to know what it is and how to fix it?

1999 MITSUBISHI ECLIPSE
90,000 MILES • 2.0L • 4 CYL • 2WD • AUTOMATIC
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ECLIPSEKRYPT
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This code popped out and I would like to know what it is and how to fix it. I haven't found much info on the internet about it. Please help any info would be highly appreciated.
Thanks in advance.
Nov 29, 2024 at 5:18 PM
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JACOBANDNICKOLAS
  • ASE Certified Mechanic
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Hi,

The code is a transmission code. It is related to a pressure switch. This vehicle has three of them. To determine if it a switch related is or something other causing it, there are different steps/tests to make the determination.

If you look below, I attached the diagnostics related to it. Take a look through them and let me know if you are comfortable performing them or if you have other questions.

Let me know.

Joe

See pics below.
Nov 29, 2024 at 7:35 PM
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STEVE W.
  • ASE Certified Mechanic
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That is a transmission code. Basically, the TCM is seeing the pressure switch for the Low-Reverse solenoid is sending the wrong signal. That is part of the solenoid pack. To test it you unplug the control cable to the transmission and then test the resistance between pins 4 and 6. If it fails the test, you replace the solenoid pack and the pressure switch assembly which is part of the valve body. It is part number 04504570AB. Before you go through that and change the valve body, I would suggest changing the fluid and filter in the transmission and then see if it comes back.
Nov 29, 2024 at 7:57 PM
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ECLIPSEKRYPT
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Thank you for your answers i will have this tested and will give the fluid change a try.
Dec 1, 2024 at 5:02 PM
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JACOBANDNICKOLAS
  • ASE Certified Mechanic
  • 110,194 POSTS
  • ASE Certified Mechanic
Hi,

If you have a chance, let us know what you find. We are interested in knowing.

Take care,

Joe
Dec 1, 2024 at 10:00 PM
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ECLIPSEKRYPT
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Thank you, will do. I should be getting to work this Saturday. Since i will be off and my friend has a lift. Keep you posted.
Dec 2, 2024 at 4:24 PM
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ECLIPSEKRYPT
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Sorry I took long to answer just with the holidays and work to me awhile to get to the car. I changed the part and drives a lot better. Thank you for all your help.
Feb 5, 2025 at 7:15 PM
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