P1810 - FAULT CODE - OBD2

P1810 BUICK, CADILLAC, CHEVROLET, FORD, GMC, PONTIAC, SATURN: TRANSMISSION FLUID PRESSURE VALVE POSITION SWITCH CIRCUIT

The automatic manual Transmission Fluid Pressure (TFP) valve position switches consist of five pressure switches, two of which are normally closed and three of which are normally open. A Transmission Fluid Temperature sensor (TFT) is also included, and they are all combined into one body-mounted unit.

The PCM (Powertrain Control Module) provides the required ignition voltage for each range signal. Once connected to at least one of the circuits via the pressure switch combinations, the PCM detects which manual valve position has been selected. Subsequently, the Powertrain Control Module compares the actual voltage combination of the switches with those indicated in a table of combinations that are stored in its memory. The manual valve position switch of the TFP valve does not differ between the stop and neutral, because the valve bodies’ pressures are very alike.

The P1810 OBDII fault code is set on Cadillac, Chevrolet, Ford, GMC, and other vehicles when the PCM detects an invalid state from the TFP manual valve position switch by decoding the manual valve position switch inputs.

• Check Engine Lamp illuminated.
• Problems during gear changes.
• Problems starting the engine.
• The motor is unstable.
• Low voltage and voltage

The reasons for the OBD2 DTC P1810 code being set are:

• Transmission Fluid Pressure manual valve position switch harness may have been damaged.
• The TFP manual valve position switches circuit electrical connections may have deficiencies causing a short circuit.
• The TFP valve position switch could be defective.
• Low or dirty oil.
• On-board computer damaged.
• PCM error.

The corresponding steps to troubleshoot the P1810 OBDII diagnostic code are:

• As a first step consult the Technical Service Bulletins.
• Inspect the wiring of the TFP valve position switch circuit and check it for common damage. If burns or wear are found, make the appropriate repairs.
• Using appropriate tools measures TFP valve position switch circuit voltages. Compare the readings obtained with those indicated in the manufacturer's specifications and if inconsistencies are found, make the necessary repairs.
• Check the integrity of the TFP valve position switch by following the diagnostic steps for that component. If damage is found on the switch, consider replacing it.