GM Service Manual Online
For 1990-2009 cars only

DTC P0705 Non Europe or N American Emissions

Table 1: Gear Position and Range Signal Chart

Conditions for Setting the DTC

The P/N switch wiring harness is shorted to ground or open.

Action Taken When the DTC Sets

No lamp control is required but diagnostic information should be stored immediately when the malfunction is detected.

Conditions for Clearing the DTC

    • A history DTC will clear after 40 consecutive warm-up cycles without a fault.
    • The scan tool can clear the DTC from the transmission control module (TCM) history.

Diagnostic Aids

    • An intermittent problem may be caused by a poor connection, rubbed-through wiring insulation, or a wire that is broken inside the insulation.
    • Any circuitry that is suspected as causing the complaint should be thoroughly inspected for the following conditions:
       - Backed-out terminals
       - Improper mating
       - Broken locks
       - Improperly formed
       - Damaged terminals
       - Poor terminal-to-wire connection

Gear Position and Range Signal Chart

Gear Position

L1

L2

L3

L4

P

0

0

12

0

R

0

0

0

12

N

0

12

0

0

D

12

12

12

0

3

12

12

0

12

2

12

0

12

12

1

0

12

12

12

Step

Action

Values

Yes

No

1

Did you perform the Diagnostic System Check-Automatic Transmission?

--

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission

2

  1. Install the scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Record, then clear the DTCs.
  4. Turn OFF the ignition.
  5. Turn ON the ignition, with the engine OFF.
  6. Apply the brakes and select each transaxle range P, R, N, D, 3, 2, 1, while monitoring the scan tool. Refer to the Gear Position and Range Signal Chart above.

Does each selected transaxle range match the scan tool and signal range chart?

--

Go to Step 3

Go to Diagnostic Aids

3

  1. Turn OFF the ignition.
  2. Disconnect the transmission control module (TCM) wiring harness connector and the engine control module (ECM) wiring harness connector.
  3. Measure the resistance between terminal C13 of the TCM connector and terminal B8 of the ECM connector.

Is the resistance within the specified range?

∞ ohms

Go to Step 4

Go to Step 5

4

Repair the wiring harness connector.

Did you find and correct the condition?

--

Go to Step 7

--

5

  1. Turn OFF the ignition.
  2. Measure the voltage of the TCM wiring harness terminal C13.

Is the connection condition OK?

--

Go to Step 4

Go to Step 6

6

Replace the TCM. Refer to Transmission Control Module Replacement .

Is the replacement complete?

--

Go to Step 7

--

7

  1. After the repair, use the scan tool Clear Info function and road test the vehicle.
  2. Review the DTC Info.

Has the last test failed or is the current DTC displayed?

--

Go to Step 2

System OK

DTC P0705 European and N American Emissions

Table 1: Gear Position and Range Signal Chart

Circuit Description

The transmission range (TR) switch, or park/neutral position (PNP) is located on the selector shaft and informs the transmission control module (TCM) of the current selector lever position P-R-N-D-3-2-1.

The selector lever position is transmitted to the TCM in encoded form along 4 lines. The encoding is such that malfunctions in the connecting lead are identified.

The TR switch is located on the selector shaft, which is connected to the selector lever via a pull cable. In addition, the TR switch controls the starter interlock, the reverse lights and the selector lever position indicator on the instrument panel.

Conditions for Setting the DTC

    • The TR switch is stuck to closed.
    • The TR switch wiring harness is short to ground.
    • The TR switch wiring harness is short to power.
    • Immediately after the preceding condition occurs.

Action Taken When the DTC Sets

    • The malfunction indicator lamp (MIL) will illuminate.
    • The TCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer.
    • Adopt Emergency/Substitute mode and constant 4th gear.

Conditions for Clearing the MIL/DTC

    • The MIL will turn OFF when the malfunction has not occurred after 3 ignition cycles.
    • A history DTC will clear after 40 consecutive warm up cycles without a fault.
    • Using a scan tool can clear history diagnostic trouble codes (DTCs).

Diagnostic Aids

    • When DTC P0705 sets, the possible cause of TR switch.
    • An intermittent problem may be caused by a poor connection, rubbed-through wiring insulation, or a wire that is broken inside the insulation.
    • Any circuitry that is suspected as causing the complaint should be thoroughly inspected for the following conditions:
       - Backed-out terminals
       - Improper mating
       - Broken locks
       - Improperly formed
       - Damaged terminals
       - Poor terminal-to-wire connection

Gear Position and Range Signal Chart

 

L1

L2

L3

L4

P

0

0

12

0

R

0

0

0

12

N

0

12

0

0

D

12

12

12

0

3

12

12

0

12

2

12

0

12

12

1

0

12

12

12

Step

Action

Values

Yes

No

1

Did you perform the Diagnostic System Check-Automatic Transmission?

--

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission

2

  1. Install the scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Record then clear diagnostic trouble codes (DTCs).
  4. Turn the ignition OFF.
  5. Turn ON the ignition, with the engine OFF.
  6. Apply the brakes and select each transaxle range, P-R-N-D-3-2-1, while monitoring the scan tool.
  7. Refer to the Gear Position and Range Signal Chart.

Does each selected transaxle range match the scan tool and signal range chart?

--

Go to Step 3

Go to Diagnostic Aids

3

Inspect the F10 for an open.

Was a problem found?

--

Go to Step 4

Go to Step 5

4

Replace the fuse as necessary.

Did you complete the replacement?

--

System OK

--

5

Inspect the TR switch. Refer to Diagnostic Aids.

Was the problem found?

--

Go to Step 6

Go to Step 7

6

Replace the TR switch. Refer to Park/Neutral Position Switch Replacement .

Did you complete the replacement?

--

System OK

--

7

  1. Disconnect the TR switch connector and TCM connector.
  2. Measure the resistance between terminal 3 of the TR switch and terminal C1 of the TCM connector.
  3. Measure the resistance between terminal 2 of the TR switch and terminal B15 of the TCM connector.
  4. Measure the resistance between terminal 4 of the TR switch and terminal B6 of the TCM connector.
  5. Measure the resistance between terminal 5 of the TR switch and terminal B11 of the TCM connector.

Does the resistance measure the value shown?

0 ohms

Go to Step 9

Go to Step 8

8

Repair the malfunctioning terminals as necessary.

Did you complete the repair?

--

System OK

--

9

  1. Turn ON the ignition, with the engine OFF.
  2. Measure the voltage of terminal 3.
  3. Measure the voltage of terminal 2.
  4. Measure the voltage of terminal 4.
  5. Measure the voltage of terminal 5.

Is the voltage within the specified range?

11-14 V

Go to Step 10

Go to Step 11

10

Repair the malfunctioning terminals as necessary.

Did you complete the repair?

--

System OK

--

11

Replace the TCM. Refer to Transmission Control Module Replacement .

Did you complete the replacement?

--

Go to Step 12

--

12

  1. After the repair, use a scan tool clear info function and road test the vehicle.
  2. Review the DTC info.

Has the last test failed or is the current DTC displayed?

--

Go to Step 1

System OK