Circuit Description
The park/neutral position (PNP) switch is mounted on the transmission manual shaft. The PNP switch is a multi-signal switch. The fuse block-underhood supplies ignition voltage to the PNP switch on four signal circuits, A, B, C, and P. Each gear selector lever position powers two or more of the signal circuits in a unique pattern. In order to determine the gear range selected by the driver, the transmission control module (TCM) compares the voltage combination on the signal circuits to a transmission range (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 C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0705 Transmission Range (TR) Switch Circuit
Conditions for Running the DTC
The engine run time is greater than 5 seconds and not in fuel cut off.
Conditions for Setting the DTC
The combination of TR switch signals is 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 commands an alternate coast shift pattern where downshifts occur at higher speeds while coasting. |
| • | 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. |
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 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.
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By disconnecting the PNP 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.
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This step tests the PNP switch wiring for an open or lack of a ground path from the TCM.
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This step tests the PNP 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.
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This step tests the PNP 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.
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This step tests the PNP 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.
Step | Action | Values | Yes | No | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||||||||||
2 |
Does each selected transmission range match the scan tool Transmission Range display? | -- | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 | ||||||||||||||
3 |
Does each selected transmission range match the scan tool Transmission Range display? | -- | Go to Step 17 | Go to Step 4 | ||||||||||||||
4 |
Did you find and correct a condition? | -- | Go to Step 20 | Go to Step 5 | ||||||||||||||
With the scan tool, observe the TR Switch-P/A/B/C display. Does the scan tool TR Switch-P/A/B/C parameter indicate LOW for all range signal states? | -- | Go to Step 14 | Go to Step 6 | |||||||||||||||
Does the scan tool TR Switch-P/A/B/C parameter indicate LOW for all range signal states? | -- | Go to Step 7 | Go to Step 11 | |||||||||||||||
Does the voltage measure within the specified value at all four terminals? | 10-14 V | Go to Step 8 | Go to Step 12 | |||||||||||||||
Connect a fused jumper wire from the TR signal A circuit of the PNP switch connector to battery positive while monitoring the scan tool TR Switch -P/A/B/C parameter. When the TR signal A circuit is shorted to voltage, do any other signal circuits indicate HI? | -- | Go to Step 13 | Go to Step 9 | |||||||||||||||
Connect a fused jumper wire from the TR signal B circuit of the PNP switch connector to battery positive while monitoring the scan tool TR Switch -P/A/B/C parameter. When the TR signal B circuit is shorted to voltage, do any other signal circuits indicate HI? | -- | Go to Step 13 | Go to Step 10 | |||||||||||||||
10 | Connect a fused jumper wire from the TR signal C circuit of the PNP switch connector to battery positive while monitoring the scan tool TR Switch -P/A/B/C parameter. When the TR signal C circuit is shorted to voltage, do any other signal circuits indicate HI? | -- | Go to Step 13 | Go to Step 18 | ||||||||||||||
11 | Test the TR signal circuit or circuits of the PNP switch that did not indicate LOW for a short to voltage. Refer to Testing for a Short to Voltage and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 19 | ||||||||||||||
12 | Test the TR signal circuit or circuits of the PNP switch that did not indicate proper voltage for an open. Refer to Testing for Continuity and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 19 | ||||||||||||||
13 | Test the affected TR signal circuits of the PNP switch for a shorted together condition. Refer to Testing for Continuity and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 19 | ||||||||||||||
14 |
Did you find the condition? | -- | Go to Step 15 | Go to Step 16 | ||||||||||||||
15 |
Important: The condition that affects this circuit may exist in other connecting branches of the circuit. Refer to Power Distribution Schematics for complete circuit distribution. Test the Ignition 0 voltage circuit of the PNP switch for a short to ground. Refer to Testing for Short to Ground and Wiring Repairs . Did you correct the condition? | -- | Go to Step 20 | -- | ||||||||||||||
16 | Test the Ignition 0 voltage circuit of the PNP switch for an open. Refer to Testing for Continuity and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 20 | Go to Step 18 | ||||||||||||||
17 | Replace the electronic PRNDL module. Refer to Transmission Control Replacement . Did you complete the replacement? | -- | Go to Step 20 | -- | ||||||||||||||
18 | Replace the PNP switch. Refer to Park/Neutral Position Switch Replacement . Did you complete the replacement? | -- | Go to Step 20 | -- | ||||||||||||||
19 | Replace the TCM . Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 20 | -- | ||||||||||||||
20 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | Go to Step 21 | Go to Step 2 | ||||||||||||||
21 | With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK |
