Tech Tip: Tacoma’s MIL Is On with DTC P0705 Set – UnderhoodService

Tech Tip: Tacoma’s MIL Is On with DTC P0705 Set

Some 2005-’09 model year Toyota Tacoma vehicles may exhibit an MIL On condition with DTC P0705 (Transmission Range Sensor Circuit Malfunction [PRNDL Input]) stored.

Some 2005-’09 model year Toyota Tacoma vehicles may exhibit an MIL On condition with DTC P0705 (Transmission Range Sensor Circuit Malfunction [PRNDL Input]) stored.

figure 1Common symptoms with this DTC can include possible delayed engagement into Reverse or Drive and possible harsh gear engagement when shifting between Park or Neutral into all other gears.

Follow the procedure in this TSB to determine if this service bulletin is applicable and to repair the vehicle.

Repair Procedure Overview
1. Review the DTC P0705 freeze-frame data to determine if this TSB may be applicable.

2. Attempt to duplicate the DTC using testing procedure shown in this TSB to confirm TSB
application.

3. If the DTC cannot be duplicated, examine the indicated wire harness electrical connector and
junction block for evidence of liquid or corrosion.

4. If liquid or corrosion is observed in indicated wire harness connector and junction block, replacement of the engine room main wire harness and junction block connector No. 1 will be required to repair the vehicle.

figure 2Repair Procedure
1. Confirm that DTC P0705 is stored in the freeze-frame data.

2. Print out the freeze-frame data for P0705 to allow easy review of data values. Note the values of the
following parameters in the Data List:
– Neutral Position SW Signal
– Shift SW Status (R Range)
– Shift SW Status (D Range)
– Shift SW Status (4 or D)
– Shift SW Status (3 Range)
– Shift SW Status (2 Range)
– Shift SW Status (L Range)
– Stop Light Switch

3. Is the Neutral Position SW Signal value on or off in the freeze-frame data?

Note: In Figure 1, the transmission is not in any gear position on this vehicle.
– If the Neutral Position SW Signal is off, this TSB does not apply. Refer to the applicable model year Tacoma repair manual for diagnostics for DTC P0705. If the Neutral Position SW Signal is on, go to step 4.

4. Are any of the following data list parameters on when the Neutral Position SW Signal is on?
– Shift SW Status (R Range)
– Shift SW Status (D Range)
– Shift SW Status (4 or D)
– Shift SW Status (3 Range)
– Shift SW Status (2 Range)
– Shift SW Status (L Range)

If no, this TSB does not apply. Refer to the applicable model year Tacoma repair manual for diagnostics for DTC P0705.

Figure 35. Using Techstream, clear all stored DTCs and then attempt to duplicate the MIL On DTC P0705.

6. Prepare the Techstream Data List for performing the testing/duplication procedure in step 7.

Hint: Using the Snapshot feature of Techstream makes it easier to review data and confirm duplication of this issue.

(Refer to the University of Toyota online training class P901C “Techstream InDepth” for information about taking snapshots and graphing snapshots on Techstream.)

a. Data List setup: Select AT Datalist

b. Configure Snapshot as follows: 30-second duration Trigger point at Start (0%)

c. Select Data Graph Display. Select the following data parameters for display on the line graphs:
– Shift SW Status (R Range)
– Shift SW Status (D Range)
– Neutral Position SW Signal
– Stop Light Switch

7. Duplication test procedure. The following inspection procedure can be performed with the vehicle on the lift or while driving the vehicle. If driving, select an area with no traffic since extensive stopping and shifting between the Park,

Neutral, Reverse and Drive positions is required with the brake pressed and released in all gear positions.

a. Clear all stored DTCs using Techstream.

b. Start the vehicle.

c. Start Snapshot.

d. Shift between the Park, Reverse, Neutral and Drive positions.

e. Ensure engagement in all gear positions selected.

f. Press and release the brake pedal when in all gear positions (this can be performed multiple times).

g. Review Snapshot after completing the test to confirm if abnormal readings are observed.

See Figure 2.

h. Does the Neutral Position SW Signal show “On” at any time when in Reverse or Drive?
– If YES – Go to step 7i.
– If NO – Go to step 8.

Note: Neutral Position SW Signal can show “On” either with the Stop Lamp Switch on or off.

i. Does the Neutral Position SW Signal change based on brake pedal input (Stop Lamp Switch on or off) when in Reverse or Drive?
– If YES – Ground through Stop Lamp Circuit
confirmed. Go to step 9.
– If NO – TSB does not apply. Refer to the applicable model year Tacoma Repair Manual for diagnostics for DTC P0705.

8. Inspect connector DD and Junction Block No. 1 for liquid contamination or corrosion.

a. Disconnect the battery.

b. Locate connector DD and Junction Block No. 1.

c. Remove the left front kick panel.

d. Identify connector DD and Junction Block No.1

See Figure 3.

e. Disconnect connector DD from Junction Block No. 1.

f. Carefully inspect both components for liquid or corrosion in the connector and the junction block (especially the male and female terminals).

9. Replace the Engine Room Main Wire Harness and Junction Block No. 1.

10. Reconnect the battery.

11. Confirm the proper operation of the vehicle.

12. Repair is complete.

Courtesy of ALLDATA.

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