For 1990-2009 cars
Automatic Transmission Components
Automatic Transmission Controls Schematics
OBD II Symbol Description Notice

### Circuit Description

The Transmission Range Switch is attached externally to the left side of the 4L30-E transmission on the gear selector shaft. The Transmission Range Switch informs the TCM and the Gear Position Indicator (on the console) which gear the driver selects.

The ignition voltage applies to terminal D of the Transmission Range Switch. Depending on the selector lever position, this ignition voltage connects to the various combinations of terminals A, B, C, and G of the Transmission Range Switch. The TCM decodes these combinations in order to determine gear position.

### Conditions for Running the DTC

The ignition is on.

### Conditions for Setting the DTC

The switch indicates an undefined position for longer than 20 seconds.

### Action Taken When the DTC Sets

• | The TCM illuminates the Service Transmission Lamp (STL) and sends a MIL Request to the ECM on the second consecutive drive trip that the diagnostic runs and fails. The ECM then illuminates the MIL.

• | The ECM records the operating conditions in the Freeze Frame at the time of the MIL Request from the TCM.

• | The transmission operates in the Default Mode.

### Conditions for Clearing the MIL/DTC

• | The TCM turns off the STL as soon as the fault is no longer present.

• | The ECM turns off the MIL after three consecutive drive trips during which the TCM sends no MIL Request.

• | A History DTC clears after forty consecutive warm-up cycles, if no failures are present by this diagnostic or any other emission related diagnostic.

• | The scan tool clears the MIL/DTC.

### Diagnostic Aids

Use the Connector Test Adapter Kit J 35616-A for any test that requires probing the TCM harness connector or a component harness connector. Using this kit will prevent damage to the harness connector terminals.

Check for the following conditions:

• | Poor connections at the TCM or at the component. Inspect the harness connectors for any backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection. Refer to Engine Electrical, Troubleshooting Procedures, Checking Terminal Contact for proper procedure.

• | Damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the scan tool while moving any related connectors and any wiring harnesses. A change in the display may help to locate the fault.

### Test Description

The number(s) below refer to the step number(s) on the Diagnostic Table.

1. The scan tool display should match the selector lever position at each detent stop. If the lever has to be moved slightly within a position to get the right indication on the scan tool, the Transmission Range Switch adjustment should be checked. Refer to Automatic Transmission, On-Vehicle Service, Transmission Range Switch.

2. Terminal D in the mating connector (harness side) can be used as the power source.

#### DTC P0705 - Transmission Range Switch Circuit

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to Step 2 | Go to Powertrain On Board Diagnostic (OBD) System Check
2 |

1. Turn off the engine.
2. Turn on the ignition.
3. Shift through all of the selector lever positions while observing the Transmission Range on the scan tool.

Does the scan tool display agree with the selector lever in all of the positions?

P, R, N, D, 3, 2, 1

No trouble found

Refer to Diagnostic Aids

Go to Step 3

3 |

1. Disconnect the Transmission Range Switch.
2. Use the test light J 35616-200 connected to ground in order to probe terminal D in the harness connector (harness side).

Does the test light illuminate?

--

Go to Step 4

Go to Step 6

4 |

1. Use a fused jumper in order to jumper terminal D in the harness connector (switch side) to B+.
2. Use the test light J 35616-200 connected to ground in order to probe all of the terminals in the harness connector (switch side) in each selector lever position. In the following list, only the specified terminals should illuminate the test light in a given gear position:

• | P: Terminals D, A, G

• | R: Terminals D, A, B, F

• | N: Terminals D, B, G

• | D: Terminals D, B, C

• | 3: Terminals D, A, B, C, G

• | 2: Terminals D, A, C

• | 1: Terminals D, C, G

Did the test light illuminate on the proper terminals in each gear position?

--

Go to Step 5

Go to Step 9

5 |

1. Reconnect the Transmission Range Switch.
2. Turn off the ignition.
3. Disconnect the TCM.
4. Turn on the ignition with the engine off.
5. Probe terminals 8, 23, 26, and 33 in the TCM harness connector in each selector lever position with the test light J 35616-200 connected to ground. In the following list, only the specified terminals should illuminate the test light in a given gear position:

• | P: Terminals 23, 33

• | R: Terminals 23, 26

• | N: Terminals 26, 33

• | D: Terminals 8, 26

• | 3: Terminals 8, 23, 26, 33

• | 2: Terminals 8, 23

• | 1: Terminals 8, 33

Did the test light illuminate on the proper terminals in each gear position?

--

Go to Step 11

Go to Step 7

6 | Repair the ignition feed circuit to the Transmission Range Switch. Is the action complete? | -- | Go to Step 13 | --
7 | Check the Transmission Range Switch harness connector for a poor connection or poor terminal tension. Refer to Engine Electrical, Troubleshooting Procedures, Checking Terminal Contact for proper procedure. Was a problem found and corrected? | -- | Go to Step 13 | Go to Step 8
8 | Check the affected circuit(s) for the following conditions and repair as necessary:

• | open/high resistance

• | short to ground

• | short to B+

Is the action complete?

--

Go to Step 13

--

9 | Check the Transmission Range Switch for proper adjustment. Refer to Automatic Transmission, On-Vehicle Service, Transmission Range Switch . Was a problem found and corrected? | -- | Go to Step 13 | Go to Step 10
10 | Replace the Transmission Range Switch. Is the action complete? | -- | Go to Step 13 | --
11 | Check the TCM harness connector for a poor connection or a poor terminal tension. Refer to Engine Electrical, Troubleshooting Procedures, Checking Terminal Contact for proper procedure. Was a problem found and corrected? | -- | Go to Step 13 | Go to Step 12
12 | Replace the TCM. Refer to Automatic Transmission, On-Vehicle Service, TCM . Is the action complete? | -- | Go to Step 13 | --
13 |

1. Clear the DTCs on the scan tool.
2. Turn off the ignition for 15 seconds.
3. Start the engine.
4. Operate the vehicle within the conditions required for this diagnostic to run. Refer to Conditions for Running the DTC.
5. Check for any DTCs.

Is DTC P0705 set?

--

Go to Step 2

Go to Step 14

14 | Were there any additional DTCs noted during the Powertrain or Transmission OBD System Check that were not diagnosed? | -- | Go to the applicable DTC table | Go to Step 15
15 | Does the Transmission now function properly? | -- | System OK | Go to Functional Test