P1810

Circuit Description
The automatic transmission fluid pressure manual valve position switch (TFP Valve Position Switch) consists of six pressure switches (three normally-closed and three normally-open switches). Ignition voltage is applied to each of the switches. By grounding or opening 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 illegal combination on any range inputs (ON/OFF/ON or ON/ON/ON), then DTC P1810 sets. If the PCM detects a gear range other than the one indicated, then DTC P1810) sets. DTC P1810 is a Type B DTC.

Conditions for Setting the DTC
DTC P1810 sets during the second consecutive trip in which at least one of the following fail cases occurs:

Case 1
^ The engine speed is greater than 500 RPM for 5 seconds and not in fuel shut off.
^ The system voltage is 9-18 volts.
^ The TFP Valve Position Switch indicates an illegal switch combination for 60 seconds.

Case 2
^ No Vehicle Speed Sensor (VSS) DTCs P0502 or P0503.
^ The system voltage is 9-18 volts.
^ The engine speed starts at less than 50 RPM and rises to more than 700 RPM.
^ The vehicle speed is less than 5 km/h (3 mph). ^ TFP Valve Position Switch indicates REVERSE, D2 or D4 for 7 seconds at engine start up without indicating PARK or NEUTRAL.

Case 3
^ No Throttle Position (TP) sensor DTCs P0121, P0122 or P0123.
^ No VSS DTCs P0502 or P0503.
^ No A/T ISS sensor DTCs P0716 or P0717 are set.
^ No 1-2 SS Valve DTCs P0751 or P0753.
^ No 2-3 SS Valve DTCs P0756 or P0758.
^ The engine torque is 70-230 N.m (50-170 lb ft).
^ The engine speed is greater than 500 RPM for 5 seconds and not in fuel shut off.
^ The throttle position angle is greater than 9%.
^ The gear ratio indicates REVERSE, D4, D3, D2 or D1.
^ The vehicle speed is more than 8 km/h (5 mph).
^ The TFP Valve Position Switch indicates PARK or NEUTRAL for 5 seconds.

Case 4
^ No TP sensor DTCs P0121, P0122 or P0123.
^ No VSS DTCs P0502 or P0503.
^ No A/T ISS sensor DTCs P0716 or P0717 are set.
^ No 1-2 55 Valve DTCs P0751 or P0753.
^ No 2-3 SS Valve DTCs P0756 or P0758.
^ The engine torque is 70-230 N.m (50-170 lb ft).
^ The engine speed is more than 500 RPM for 5 seconds and not in fuel shut off.
^ The throttle position angle is greater than 9%.
^ The gear ratio indicates D4, D3, D2 or D1.
^ The vehicle speed is greater than 8 km/h (5 mph).
^ The TFP Valve Position Switch indicates REVERSE for 7 seconds.

Case 5
^ No TP sensor DTCs P0121, P0122 or P0123.
^ No VSS DTCs P0502 or P0503.
^ No A/T ISS sensor DTCs P0716 or P0717 are set.
^ No 1-2 SS Valve DTCs P0751 or P0753.
^ No 2-3 SS Valve DTCs P0756 or P0758.
^ The engine torque is 70-230 N.m (50-170 lb ft).
^ The engine speed is greater than 500 RPM for 5 seconds and not in fuel shut off.
^ The throttle position angle is greater than 9%.
^ The gear ratio indicates REVERSE.
^ The vehicle speed is more than 8 km/h (5 mph).
^ The TFP Valve Position Switch indicates D4, D3, D2 or D1 for 5 seconds.

Action Taken When the DTC Sets
^ The PCM illuminates the Malfunction Indicator Lamp (MIL).
^ The PCM commands maximum line pressure.
^ The PCM freezes shift adapts.
^ The PCM assumes D4 for shifting.
^ The PCM stores DTC P1810 in PCM history.

Conditions for Clearing the MIL/DTC
^ A scan tool clears the DTC from the PCM history.
^ The PCM clears the DTC from the PCM history if the vehicle completes 40 consecutive 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
^ Inspect the wiring at the PCM, the transmission 20-way connector, the 6-way TFP Valve Position Switch connector and all other circuit connecting points for the following conditions:
- A bent terminal
- A backed out terminal
- A damaged terminal
- Poor terminal tension
- A chafed wire
- A broken wire inside the insulation
- Moisture intrusion
- Corrosion
^ 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 condition may set this DTC.
^ Diagnose DTC P0705 or P0706 first, if set.
^ Inspect the TFP Valve Position Switch seals for damage.
^ Inspect the TFP Valve Position Switch for debris, or loose rivets.

Test Description
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.
4. This step tests for correct voltage from the PCM to the transmission 20-way connector.
6. This step tests for a short together between circuits 1224 (PNK), 1225 (DK BLU) and 1226 (RED).