This code keeps popping up. Does anyone know what this code means. Can't find it in my code book. TKS JOHN

 

Hope this helps





DTC P1810 TFP Valve Position Switch Circuit




Circuit Description
The automatic transmission fluid pressure (TFP) manual valve position switch
consists of five pressure switches (two normally-closed and three normally-open)
and a transmission fluid temperature (TFT) sensor combined into one unit. The
combined unit mounts on the valve body.
The powertrain control module (PCM) supplies the battery voltage for each range
signal. By grounding one or more of the circuits through various combinations of
the pressure switches, the PCM detects which manual valve position you select.
The PCM compares the actual voltage combination of the switches to a TFP manual
valve position switch combination table stored in memory.
The TFP manual valve position switch cannot distinguish between PARK and NEUTRAL
because the monitored valve body pressures are identical. With the engine OFF
and the ignition switch in the RUN position, the TFP manual valve position
switch indicates PARK/NEUTRAL. Disconnecting the transmission 20-way connector
removes the ground potential for the three range signals to the PCM. In this
case, with the engine OFF, and the ignition switch in the ON position, D2 will
be indicated.
When the PCM detects an invalid state of the TFP manual valve position switch or
the TFP manual valve position switch circuit by deciphering the TFP manual valve
position switch inputs, then DTC P1810 sets. DTC P1810 is a type B DTC.
Conditions for Running the DTC
No VSS assembly DTCs P0502 or P0503.
The system voltage is 8-18 volts.
The engine speed is greater than 300 RPM for 5 seconds.
The engine is not in fuel cutoff.
The engine torque is 40-400 lb ft.
The engine vacuum is 0-105 kPa.
Conditions for Setting the DTC
DTC P1810 sets if any of the following conditions occurs:
Condition 1
The VCM detects an illegal TFP manual valve position switch state for 60
seconds.
Condition 2
The engine speed is less than 80 RPM for 0.1 second; then the engine speed is
80-550 RPM for 0.07 second; then the engine speed is greater than 550 RPM.
The vehicle speed is less than 3 km/h (2 mph).
The VCM detects a gear range of D2, D4 or REVERSE during an engine start.
All conditions are met for 5 seconds.
Condition 3
The TP angle is 8-45%.
The VCM commands fourth gear.
The TCC is locked ON.
The speed ratio is 0.65-0.8 (speed ratio is engine speed divided by
transmission output speed).
The VCM detects a gear range of PARK or NEUTRAL when operating in D4.
All conditions are met for 10 seconds.
Action Taken When the DTC Sets
The PCM illuminates the malfunction indicator lamp (MIL) during the second
consecutive trip in which the Conditions for Setting the DTC are met.
The PCM commands D2 line pressure.
The PCM commands a D4 shift pattern.
The PCM freezes shift adapts from being updated.
The PCM stores DTC P1810 in PCM history during the second consecutive trip in
which the Conditions for Setting the DTC are met.
Conditions for Clearing the MIL/DTC
The PCM turns OFF the MIL during the third consecutive trip in which the
diagnostic test runs and passes.
A scan tool clears the DTC from PCM history.
The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up
cycles without an emission-related diagnostic fault occurring.
The PCM cancels the DTC default actions when the fault no longer exists and
the ignition switch is OFF long enough in order to power down the PCM.
Diagnostic Aids
Refer to the TFP Manual Valve Position Switch Logic table for the normal range
signals and the illegal combinations. In the table, ON is 0 volts, OFF is 12
volts.
Inspect the wiring at the PCM, the transmission connector and all other
circuit connecting points for the following conditions:
A backed out terminal
A damaged terminal
Reduced terminal tension
A chafed wire
A broken wire inside the insulation
Moisture intrusion
Corrosion
When diagnosing for an intermittent short or open condition, massage the
wiring harness while watching the test equipment for a change.
Refer to Transmission Fluid Pressure (TFP) Manual Valve Position Switch
Resistance Check , Functional Test Procedure and Transmission Fluid Pressure
(TFP) Manual Valve Position Switch Logic for further information.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
This step tests the indicated range signal to the manual valve actually
selected.
This step tests for correct voltage from the PCM to the transmission 20-way
connector.
DTC P1810 TFP Valve Position Switch Circuit
MalfunctionStepActionValue(s)YesNo
1Was the Powertrain On-Board Diagnostic (OBD) System Check performed?--Go
to Step 2 Go to Powertrain On Board Diagnostic (OBD) System Check
2Perform the following inspections:
Ensure that the transmission linkage from the select lever to the manual
valve is adjusted properly.
Perform the fluid checking procedure.
Were the inspections performed?--Go to Step 3 --
3 Install the Scan Tool .
With the engine OFF, turn the ignition switch to the ON position.
Important
Before clearing the DTC, use the scan tool in order to record the Freeze
Frame and Failure Records. Using the Clear Info function erases the
Freeze Frame and Failure Records from the PCM.
Record the DTC Freeze Frame and Failure Records.
Clear the DTC.
While the engine is idling at normal operating temperature, apply the
brake pedal.
Select each transmission range: P, R, N, D4, D3, D2 and D1.
Does each selected transmission range match the scan tool TFP Switch A/B/C
display?
Refer to Transmission Fluid Pressure (TFP) Manual Valve Position Switch
Logic table.--Go to Diagnostic AidsGo to Step 4
4 Turn the ignition OFF.
Disconnect the transmission 20-way connector (additional DTCs may set).
Install the J 39775 jumper harness on the engine side of the 20-way
connector.
With the engine OFF, turn the ignition switch to the ON position.
Using the J 39200 digital multimeter (DMM) and the J 35616-A connector
test adapter kit, check the voltage at connector terminals N, R and P.
Is B+ displayed on all three circuits?--Go to Step 6 Go to Step 5
5Inspect the circuits that did not indicate B+ for an open or short to
ground condition.
Refer to General Electrical Diagnosis Procedures in Wiring Systems.
Was an open or short to ground condition found?--Go to Step 8 Go to Step 7

 

P1810 TFP Valve Position Switch Circuit

 

Thanks for info. For some odd reason my car started surging in overdrive at 70 plus/rpm's started going up and down up and down. But under normal in town driving the car shifts and drives ok. Just started today. Have a 98 vert with a new auto trans only about 3k on trans. JOHN

 

I am having the same issue. Surging at 65 mph to 75 mph+ immediately after replacing the transmission

 

I know old thread,

But I have exact same problem. Surging in overdrive around 70mph. Code P1810 pops up. I have changed the pressure switch already.

Is this the PCM?

Anyone solved this problem? Normal in town shifting, but surging over 60mph closer to 70. and usually when car is not warmed up