42RLE Automatic Transmission
P0706-TRANSMISSION RANGE SENSOR RATIONALITY
For a complete wiring diagram Refer to Diagrams/Electrical. Electrical Diagrams
Theory of Operation
The C1 through C4 (T1, T3, T41, and T42) sense circuits communicate the shift lever position to the PCM. Each circuit is terminated at the transmission with a switch. Each switch can be either open or closed, depending on the shift lever position. The PCM can decode this information and determine the shift lever position. Each shift lever position has a certain combination of switches, which will be open and closed, this is called a PRNDL code. There are 4 switches, therefore: there are many possible combinations of open and closed switches (codes). However, there are only 9 valid codes (8 for AutoStick), one for each gear position and three recognized between gear codes. The remainder of the codes should never occur, these are called invalid codes. The following chart shows the normal switch states for each shift lever position.
- When Monitored:
Continuously with the ignition on.
- Set Condition:
The DTC will set if the controller detects an invalid PRNDL code which lasts for more than 0.042 seconds.
Always perform the 42RLE Pre-Diagnostic Troubleshooting procedure before proceeding. 42RLE - Pre-Diagnostic Troubleshooting Procedure
TRS Switch States:
Diagnostic Test
1. CHECK TO SEE IF P0706 DTC IS CURRENT
With the scan tool, perform the Shift Lever Position Test.
Select the test outcome from the following:
Test passes:
- Go To 6
Test fails with Error Code:
- Go To 2
Test fails without Error Code:
- Perform the Gearshift Adjustment Procedure.
- Perform the PRNDL Fault Clearing Procedure - Go To 7
2. CHECK THE TRANSMISSION RANGE SENSOR (TRS)
Turn the ignition off to the lock position.
Remove the Starter Relay.
CAUTION: Removal of the Starter Relay will prevent the vehicle from being started in gear.
WARNING: The Starter Relay must be removed from the PDC. Failure to do so can result in personal injury or death.
NOTE: Failure to remove the Starter Relay can cause a Transmission - No Response condition.
Install the Transmission Simulator, Miller tool #8333 and the Electronic Transmission Adapter kit.
Ignition on, engine not running.
With the scan tool, perform the Shift Lever Position Test.
When the scan tool instructs you to put the Gear Selector in a particular position, you must do so using the selector switch on the Transmission Simulator.
The LED for the gear position in question must be illuminated on the Transmission Simulator prior to pressing "ENTER" on the scan tool.
NOTE: When the scan tool requests the O/D off button be depressed, you must use the O/D OFF button in the vehicle or you will fail the Shift Lever Position Test with an error code 11 or OD-TOW/HALL STUCK OPEN.
NOTE: If the Shift Lever Position test fails, make sure to note the identification of the TRS Sense circuit for future reference.
Did the Shift Lever Position test pass?
Yes
- Remove the Oil Pan and Main Valve Body Assembly. Check for metal debris on top of the TRS Assembly. If debris is present, determine the cause of the debris and repair the transmission as necessary. If no problems are found, replace the Transmission Range Sensor (TRS).
- Perform the PRNDL Fault Clearing Procedure - Go To 7
No
- Go To 3
3. TRS SENSE CIRCUIT OPEN
Turn the ignition off to the lock position.
Disconnect the Transmission Simulator, Miller tool #8333.
Disconnect the PCM harness connectors and install Miller tool #8815.
CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller tool #8815 to perform diagnosis.
Measure the resistance of the identified (T1, T3, T41, or T42) TRS Sense circuit, from the Transmission Range Sensor (TRS) harness connector to the appropriate terminal of Miller tool #8815.
Is the resistance above 5.0 ohms?
Yes
- Repair the identified (T1, T3, T41, or T42) TRS Sense circuit for an open.
- Perform the PRNDL Fault Clearing Procedure - Go To 7
No
- Go To 4
4. TRS SENSE CIRCUIT SHORT TO GROUND
Measure the resistance between ground and the identified (T1, T3, T41, or T42) TRS Sense circuit.
Is the resistance below 5.0 ohms?
Yes
- Repair the identified (T1, T3, T41, or T42) TRS Sense circuit for a short to ground.
- Perform the PRNDL Fault Clearing Procedure - Go To 7
No
- Go To 5
5. TRS SENSE CIRCUIT SHORT TO OTHER CIRCUITS
Measure the resistance between the identified (T1, T3, T41, or T42) TRS Sense circuit and all other circuits in the Transmission Range Sensor (TRS) harness connector.
Is the resistance below 100k ohms between the identified (T1, T3, T41, or T42) TRS Sense circuit and any other circuit(s) in the Transmission Range Sensor (TRS) harness connector?
Yes
- Repair the identified (T1, T3, T41, or T42) TRS Sense circuit for a short to other circuit(s).
- Perform the PRNDL Fault Clearing Procedure - Go To 7
No
- Using the schematics as a guide, check the Powertrain Control Module (PCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the PCM. With the scan tool, perform QUICK LEARN.
- Perform the PRNDL Fault Clearing Procedure - Go To 7
6. INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set the DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
Wiggle the wiring and connectors while checking for shorted and open circuits.
With the scan tool, check the DTC EVENT DATA to help identify the conditions in which the DTC was set.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the PRNDL Fault Clearing Procedure - Go To 7
No
- Test Complete.
7. PRNDL FAULT CLEARING PROCEDURE
With the scan tool, erase Transmission DTCs.
Cycle the ignition off, then start the vehicle.
Firmly apply the brakes and shift into Overdrive.
NOTE: Vehicle must remain in Overdrive for at least 3.0 seconds.
With the brakes firmly applied, shift slowly through all gears (PRNDL) as least three times, pausing momentarily in each gear.
NOTE: If all the PRNDL lights box individually then the error was cleared.
Shift into park and turn the ignition off to the lock position.
Ignition on, engine not running.
With the scan tool, read Transmission DTCs.
Does the DTC P0706 reset, or do all the PRNDL indicators remain boxed in park or neutral?
Yes
- Return to the symptom list and perform diagnostics for P0706. P0706
- Go To 1
No
- Test Complete.
- Perform 42RLE TRANSMISSION VERIFICATION TEST. 42RLE Transmission Verification Test