VT25-E Automatic Transmission

VT25-E AUTOMATIC TRANSMISSION

DTC P0705





Circuit Description with VT25-E Automatic Transmission
The transmission range (TR) switch is part of the park/neutral position and back-up lamp switch assembly and is mounted on the transmission manual shaft. The TR switch is a multi-signal switch. The fuse block - underhood supplies ignition voltage to the TR switch on 4 signal circuits, A, B, C, and P. Each gear selector lever position powers 2 or more of the signal circuits in a unique pattern. In order to determine the gear range selected by the driver, the TCM compares the voltage combination on the signal circuits to a TR switch combination table stored in memory. Refer to Transmission Range Switch Logic.

When the TCM detects an invalid combination of TR switch signals, DTC P0705 sets. DTC P0705 is a type B DTC.

Conditions for Running the DTC
The ignition voltage is 8 - 18 volts.

Conditions for Setting the DTC
The combination of TR switch signals is invalid for 5 seconds. Refer to the Transmission Range Switch Logic table.

Action Taken When the DTC Sets
^ The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the Conditions for Setting the DTC are met.
^ The TCM turns power off to the torque converter clutch pressure control solenoid valve.
^ The TCM discontinues abuse torque management.
^ The TCM defaults the selected gear range to DRIVE.
^ The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as Freeze Frame and Failure Records.
^ The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as Failure Records.
^ The TCM stores DTC P0705 in TCM history during the second consecutive trip in which the Conditions for Setting the DTC are met.

Conditions for Clearing the MIL/DTC
^ The ECM turns OFF the MIL after the third consecutive drive trip in which the TCM does not sent a MIL illumination request.
^ A scan tool can clear the MIL/DTC.
^ The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring.
^ The TCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the TCM.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
5. By disconnecting the TR switch, the voltage supply for all TR switch circuits would be removed and the TCM should recognize all circuits as open. The scan tool should display LOW for all range signals.
6. This step tests the TR switch wiring for an open or lack of a ground path from the TCM.
7. This step tests the TR switch wiring and the TCM by providing a voltage supply through a fused jumper wire. When voltage is applied, the scan tool range signal A should change to HI.
8. This step tests the TR switch wiring and the TCM by providing a voltage supply through a fused jumper wire. When voltage is supplied, the scan tool range signal B should change to HI.
9. This step tests the TR switch wiring and the TCM by providing a voltage supply through a fused jumper wire. When voltage is applied, the scan tool range signal C should change to HI.