P0705
DTC P0705 (6.6L)
Circuit Description
The transmission range (TR) switch is part of the park/neutral position (PNP) and back-up lamp switch assembly and is externally mounted on the transmission manual shaft. The TR switch is a multi-signal switch. The transmission control module (TCM) supplies ignition voltage to the TR switch on 4 signal circuits, A, B, C, and P. Each gear selector lever position grounds one or more of the switch circuits. In order to determine the gear range selected by the driver, the TCM compares the voltage combinations on the signal circuits to a look up table stored in TCM memory. The TCM detects the selected gear range by the state change of the switch input. Refer to Transmission Range Switch Logic .
Switch input to the TCM is represented on the scan tool as HI and LOW. HI indicates an ignition voltage signal. LOW indicates a 0 voltage signal. The 4 parameters represent transmission range switch signal A, B, C and Parity.
When the TCM detects an invalid TR switch signal combination, then DTC P0705 sets. DTC P0705 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0705 Transmission Range (TR) Switch Circuit
Conditions for Running the DTC
* The system voltage is 8-18 volts.
* The engine run time is greater than 5 seconds.
Conditions for Setting the DTC
The combination of TR switch signals are invalid for 60 seconds. Refer to Transmission Range Switch Logic .
Action Taken When the DTC Sets
* The TCM does not request the engine control module (ECM) to illuminate the malfunction indicator lamp (MIL).
* 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 memory.
Conditions for Clearing the DTC
* A scan tool can clear the DTC.
* The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring.
* The TCM cancels the DTC default actions when the fault no longer exists and the DTC passes.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
5. By disconnecting the TR switch, the ground path for all TR switch circuits are removed and the TCM recognizes all circuits as open. The scan tool displays HI for all range signals.
6. This step tests the TR switch wiring for an open or the lack of the signal voltage from the TCM.
7. This step tests the TR switch wiring and the TCM by providing a ground path through a fused jumper wire. When grounded, the scan tool range signal A should change to LOW.
8. This step tests the TR switch wiring and the TCM by providing a ground path through a fused jumper wire. When grounded, the scan tool range signal B should change to LOW.
9. This step tests the TR switch wiring and the TCM by providing a ground path through a fused jumper wire. When grounded, the scan tool range signal C should change to LOW.
Step 1 - Step 7:
Step 8 - Step 15:
