After my check engine light came on my father in law plugged his diagnostic tool on it and it came back ''trouble code p1810 trans. fluid pressure valve position switch circuit malfunction i need to know what that means and how do i find it on the transmission so i can check it out

What wire ? a number of wires go to the transmission .

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DTC P1810 TFP Valve Position Switch Circuit


Circuit Description
The Automatic Transmission Fluid Pressure Manual Valve Position switch (TFP Val. Position Sw.) consists of five normally open switches. Ignition voltage is applied to each of the switches. By grounding one or more of these switches with fluid pressure from the manual valve, the Powertrain Control Module (PCM) can detect which gear range is selected.
If the PCM detects an invalid combination of the TFP Val. Position Sw., then DTC P1810 sets. DTC P1810 is a Type B DTC.

Diagnostic Aids
• Inspect the wiring for poor electrical connections at the PCM. Inspect the wiring for poor electrical connections at the transmission 20-way connector. Inspect the wiring for poor electrical connections at the 5-way TFP Val. Position Sw. connector. Look for the following problems:
- A bent terminal
- A backed out terminal
- A damaged terminal
- Poor terminal tension
- A chafed wire
- A broken wire inside the insulation
- Moisture intrusion
• When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a change.
• If a transmission overhaul was performed, ensure that the transmission fluid is at the proper level. A low fluid problem may set this DTC.
• Diagnose DTC 1520 first, if set.
• Inspect the TFP Val. Position Sw. for debris.


If you want to tackle this you need to get service repair info. from GM web site https://www.oem1stop.com/content/cadillac

or www.alldatadiy.com

You going to need wiring diagrams , componet location , pin out charts for the PCM -engine computer ,pinout of transmission 20 way connector

I have factory service repair info , for this code

DTC P1810 TFP Valve Position Switch Circuit

there is a 40 step diagnostic flow chart ,this code could be caused by wiring issue , the TFP Valve Position Switch could be bad or it could even be a bad PCM . Are you sure you want to tackel this ?

Hi

maybe the thermostat is not working or the DPDT relay is not working too...

thanks!

Check engine light on ? Hooking up a scan tool and checking for DTC'S - diagnostic trouble codes would be the first thing to do ! And then using scan tool data list for transmission inputs to TCM/ECM ! If it were a electrical problem the check engine light would be on , most of the time . You can find free wiring diagrams at http://bbbind.com/free_tsb.html

Check out this page
http://praxairsverdlovsk.ru/valve-body-and-pressure-switch-replacement/
Reviews of the car

There must have been a 'Check Engine' Light? When a 'check engine light' (MIL=Malfunction Indicator Lamp) is turned on, there is a DTC (Diagnostic Trouble Code) set/stored in the ECM/PCM (Engine Control Module/Powertrain Control Module). This code identifies which engine management system component/function experienced a malfunction. Once you pull/read this code, you may begin diagnosis. You'll need an OBDII (On-Board Diagnostics II) code reader. You should find a P07?? number stored (P07??... is a transmission code).

DTC 1784: LOW-REVERSE PRESSURE SWITCH
1.Remove transaxle relay from connector. Turn ignition on. Install scan tool and observe low-reverse pressure switch condition. Apply battery voltage to transaxle relay connector terminal No. 8. If low-reverse pressure switch stays off, go to next step. If low-reverse pressure switch turns on, go to step 4 .

2.Raise vehicle enough to allow drive wheels to spin freely. Test low-reverse clutch hydraulic pressure. See HYDRAULIC PRESSURE TESTS under TESTING. If low-reverse clutch pressure test is not within specification, internal transaxle failure exists. If low-reverse clutch pressure test is within specification, observe scan tool.

3.If low-reverse pressure switch turns on, trouble code is intermittent. Check wire harnesses and connectors for damage or poor connection. If low-reverse pressure switch does not turn on, replace solenoid and pressure switch assembly. Recheck trouble codes. If trouble code resets, replace TCM.

4.Check and repair wiring harness between transaxle relay connector and solenoid and pressure switch assembly connector. If wiring harness is okay, check wire between TCM connector terminal No. 10 and solenoid and pressure switch assembly.

5.If wire between TCM connector terminal No. 10 and solenoid and pressure switch assembly is okay, check TCM and solenoid and pressure switch assembly connectors. Repair connectors as necessary. If connectors are okay, recheck trouble codes. If trouble code resets, replace solenoid and pressure switch assembly. Recheck trouble codes. If trouble code resets, replace TCM.

P0700-The Transmission Control Module (TCM) monitors the malfunction of sensors and actuators relating to transmission control. When the TCM detects a malfunction with the control, a signal is send to the Engine Control Module (ECM) to trigger the Engine Light or Service Engine Soon light. The ECM stores the P0700 code and it means the TCM detected a malfunction with the transmission controls.

I would try disconnecting he battery and letting it sit for 5 minutes, then hook it back up to see if they return-the 700 code is probably related to the 1784 code, that seems to be your main issue.

Hook that diagnostic computer to the car. If the cod reads P1810 then u need a Pressure Control Solenoid. Your check engine light will not come on with this code. The mechanic will have to drop the transmission to install the solenoid. Have a 2000 pontiac bonneville that had the same problem and ever since I did the solenoid change I have had no other problems.

you might want to see if your cadilatic converters pluged alot of times that will cause too much back pressure if a check engine light came on than it might be your oyxgen sensor if not chances its something else but most likley its your catilatic converter
either wise you can check your plugs, wires, fuel filter, air filter, cap and rotor if it has one and even check the coil.

Do you also have a check engine light on as well?
Go to an auto parts store like autozone where they'll plug it up to a scan tool for the trouble code for free.
How do the forward gears react?...shifts rough?...clunks through gears?...slips? (engine speeding up but forward travel isnt)

Start on level ground...engine cooled.
If low or missing trans. fluid...any leaks?
Check for trans. fluid in the radiator (not the recovery). The radiator is a cooling unit for the fluid and in some cases can rupture , pushing fluid into the radiator itself. Check especially up towards the radiator area where the trans. fluid lines go into the radiator.

Is the access door for the oil filter in place? It needs to be.(has to do with cooling, and area of greater/lesser air resistense)
How about the fluid...smell?...dirty?...gooey?

For trans fluid ,check trans fluid level with engine on, hot and running in park, on level ground.

You have a 4L60E M30 series transmission. Has certain components (valves-solenoids) in it that can keep transmissions from shifting properly should the fluid overheat or the pressure become too high/low.
The usual trouble code this displays is P1870.
Sometimes it is simply a TCC valve out of whack and can be replaced

check 1st 2nd shift solenoid (lift it of the box check passage way is clear ) use genuine fluid i cant strees this enough (9 years working on hondas taught me ) it works so many problems solved with a simple oil change