P1810

DTC P1810

Schematic:

Circuit Description
The automatic Transmission Fluid Pressure (TFP) manual valve position switch consists of six pressure switches. Five of the switches are normally-open, and determine gear range selection. The sixth switch is normally-closed, and detects Torque Converter Clutch (TCC) release fluid pressure. The TFP manual valve position switch also contains the automatic Transmission Fluid Temperature (TFT) sensor. These components are combined into one unit, attached to the control valve body.
The PCM provides battery voltage on the three range signal circuits. By grounding one or more of the switches with fluid pressure from the manual shift valve, the PCM detects the selected gear range. When you disconnect the transmission electrical connector and the ignition is ON, the ground potential for three range signals from the PCM will be removed, and an invalid gear range will be indicated.
When the PCM detects any of the following conditions, DTC P1810 sets.
- An invalid gear range
- A gear range other than PARK/NEUTRAL indicated at start-up
- A gear range which does not agree with the current gear ratio

DTC P1810 is a type B DTC.

Conditions for Running the DTC
- The engine is running.
- The system voltage is 8 - 18 volts.

Conditions for Setting the DTC
One of the following three cases occurs:

Case 1
The gear range is invalid for 60 seconds.

Case 2
- No VSS DTCs P0502 or P0503.
- The engine speed is in transition from 0 RPM to greater than 600 RPM.
- The vehicle speed is less than 3 km/h (2 mph).
- D2, D4 or Reverse gear is indicated after start-up for 2 seconds.

Case 3
- No TP DTCs P0121, P0122, or P0123.
- No VSS DTCs P0502 or P0503.
- No AT ISS DTCs P0716 or P0717.
- No shift solenoid DTCs P0751, P0753, P0756 or P0753.
- The TP is 10-25 percent.
- The vehicle speed is 8 km/h (5 mph) or greater.
- The engine torque is greater than 14 Nm (10 ft. lbs.).
- All of the above conditions are met and one of the following occurs for 5 seconds:
- The TFP manual valve position switch indicates PARK/NEUTRAL when the gear ratio is less than 0.72:1, 4th gear.
- The TFP manual valve position switch indicates REVERSE when the gear ratio is greater than 2.23:1, or less than 2.02:1.
- The TFP manual valve position switch indicates D4, D3, D2 or D1 when the gear ratio indicates REVERSE.

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 elevates line pressure.
- The PCM assumes a D4 shift pattern.
- The PCM freezes transmission adapt functions.
- The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame and Failure Records.
- 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 can clear the MIL/DTC.
- 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 ignition switch is OFF long enough in order to power down the PCM.

Test Description

Steps 1-3:

Steps 4-10:

Steps 11-17:

The numbers below refer to the step numbers on the diagnostic table.
3. This step tests the indicated range signal to the manual valve range actually selected.
6. This step tests for correct voltage from the PCM.