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

### Circuit Description

The Transmission Range Switch attaches 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 the gear position.

### Conditions for Running the DTC

For Position N or P:

• | The engine is speed greater than 500 RPM but less than 3000 RPM.

• | The throttle position is greater than 34 percent.

• | DTC P0120 is not set.

For Position R the output speed greater than 8160 RPM.

### Conditions for Setting the DTC

• | For Position N or P: Position N or P detected

• | For Position R: Position R detected

• | Above conditions met for longer than 3 seconds.

### Action Taken When the DTC Sets

• | The MIL/STL will not illuminate.

• | The TCM memory stores the DTC at the time of the first failure.

### Conditions for Clearing the MIL/DTC

• | A History DTC clears after forty consecutive warm-up cycles if no failures are present by this or any other non-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 you have to move the lever 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 P0706 - Transmission Range Switch Performance

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 scan tool.

Does the scan tool display agree with the selector lever in all 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. Probe terminal D in the harness connector (harness side) with the test light J 35616-200 connected to ground.

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. Use the test light J 35616-200 connected to ground in order to probe terminals 8, 23, 2, and 33 in the TCM harness connector 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 23, 33

• | R: Terminals 23, 26

• | N: Terminals 26l 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 for a poor connection or a poor terminal tension. Refer to Engine Electrical, Troubleshooting Procedures, Checking Terminal Contact for the 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 with 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 P0706 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 have not been diagnosed? | -- | Go to the applicable DTC table | Go to Step 15
15 | Does the Transmission now function properly? | -- | System OK | Go to Functional Test