Operation CHARM: Car repair manuals for everyone.

P2806






P2806-TRANSMISSION RANGE SENSOR ALIGNMENT





For a complete wiring diagram refer to Diagrams/Electrical. Electrical Diagrams


Theory of Operation


The Transmission Range Sensor (TRS) is a multiple position selector switch which changes the signal path by redirecting a 12-volt signal source to seven different TRS signal circuits (P, R, N, D, 3, 2, 1) and also houses a Park/Neutral (P/N) switch circuit. These circuits are monitored by the Transmission Control Module and used in conjunction with various pressure switches to validate proper operation of the transmission and diagnose any possible problem. In a normal operating mode, pressure switch 8, is in an "Off" state in P, R, or N. and in an "On" state in any forward gear (engine running). If the TCM detects all of shift lever positions registering "OPEN", the code will set and the PRNDL display will have all of the Shift Lever positions boxed. This DTC will not illuminate the MIL



When Monitored:
- Ignition on, engine running.
- Pressure Switch 8 is off.

Set Condition:
- When the Transmission Control Module (TCM) detects all of the Shift Lever positions registering "OPEN" for the period of 2 seconds.







Always perform the AS68RC Pre-Diagnostic Troubleshooting procedure before proceeding. AS68RC Pre-Diagnostic Troubleshooting Procedure



Diagnostic Test


1. CHECK IF DTC IS CURRENT

NOTE: This DTC may set if the shift lever is positioned between gears or if Transmission Range Sensor has been replaced or reinstalled and not properly adjusted (calibrated). Verify with the customer when the symptom occurred. If the DTC was set while the Shift Lever was in between gears, clear the DTC and verify proper operation. Make sure the TRS is properly adjusted before attempting to perform this diagnostic procedure. If the TRS was improperly adjusted, adjust as necessary and perform AS68RC VERIFICATION TEST AS68RC Transmission Verification Test

With the scan tool, read Transmission DTCs.

Is the status Active or is the Starts Since Set counter 2 or less for this DTC?

Yes

- Go To 2

No

- Go To 7



2. CHECK THE TRS CONNECTOR

Turn the ignition off to the lock position.

Inspect the TRS harness connector.

Is the TRS harness connector unplugged or not fully seated?

Yes

- Repair or replace the TRS harness connector as necessary.
- Perform AS68RC VERIFICATION TEST. AS68RC Transmission Verification Test

No

- Go To 3



3. CHECK THE TRANSMISSION RANGE SENSOR STATES

Ignition on, engine not running.

With the scan tool, monitor the TRS states (Open-Closed) in the following steps:

Slowly move the shift lever to all positions (P, R, N, D, 3, 2, 1) while noting the TRS states.

Is there a shift position that shows all of the TRS positions as "Open"?

Yes

- Go To 4

No

- Go To 7



4. CHECK THE (F1) FUSED IGNITION SWITCH OUTPUT (OFF-RUN-START) CIRCUIT FOR AN OPEN





Turn the ignition off to the lock position.

Disconnect the TRS harness connector.


NOTE: Check connectors - Clean/repair as necessary.

Ignition on, engine not running.

Using a test light connected to ground, check the (F1) Fused Ignition Switch Output (Off-Run-Start) circuit.


NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.

Does the test light illuminate brightly?

Yes

- Go To 5

No

- Repair the (F1) Fused Ignition Switch Output (Off-Run-Start) circuit for an open.
- Perform AS68RC VERIFICATION TEST. AS68RC Transmission Verification Test



5. CHECK THE TRANSMISSION RANGE SENSOR





Ignition on, engine not running.

With the scan tool, monitor the TRS circuits in the following steps.

Using a jumper wire, jump each TRS circuit one at a time to the (F1) Fused Ignition Switch Output (Off-Run-Start) circuit in the TRS harness connector.

Do the TRS circuits read as "Closed" on each circuit when connected with a jumper wire?

Yes

- Replace the Transmission Range Sensor.
- Perform AS68RC VERIFICATION TEST. AS68RC Transmission Verification Test

No

- Go To 6



6. CHECK THE CONNECTORS

Turn the ignition off to the lock position.

Using the schematics as a guide, check the identified circuit from the previous step for an open.

Wiggle the wires while checking for open circuits.

Was there any problems found?

Yes

- Repair as necessary.
- Perform AS68RC VERIFICATION TEST. AS68RC Transmission Verification Test

No

- Using the schematics as a guide, check the Transmission Control Module (TCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for Service Information Tune-ups or Service Bulletins for any possible causes that may apply. If no problems are found, replace and program the TCM.
- Perform AS68RC VERIFICATION TEST. AS68RC Transmission Verification Test



7. CHECK 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 wires while checking for shorted and open circuits.

Check for any Service Bulletins that may apply.

Verify with the customer when the symptom occurred. If the DTC was set while the Shift Lever was in between gears, clear the DTC and verify proper operation.

Were there any problems found?

Yes

- Repair as necessary.
- Perform AS68RC VERIFICATION TEST. AS68RC Transmission Verification Test

No

- Test Complete.