Circuit Description

The TFP manual valve position switch assembly consists of 5 pressure switches and a Transmission Fluid Temperature (TFT) sensor. Two switches are normally closed. Three other switches are normally open. Complete assembly mounts on control valve body.

The PCM supplies battery voltage to each range switch. PCM grounds one or more range switch signal circuit(s) through various combinations of pressure switches. PCM monitors combinations in order to detect what manual valve position has been selected. PCM compares actual voltage combination of switches to TFP manual valve position switch combination values stored in memory. TFP manual valve position switch cannot distinguish between Park and Neutral because monitored valve body pressures are identical. DTC P1810 is set if PCM detects an invalid state of TFP manual valve position switch. See TFP MANUAL VALVE POSITION SWITCH LOGIC  table under DESCRIPTION & OPERATION.