Canada - A/T/Engine Controls - MIL ON/DTC P0770 Shift Solenoid
Bulletin
1188
Issue Date
2003-02-03
Reference
EE-02-016
Model
4Runner, Tacoma
Year Range
2002
Market
Canada
Component
AT, EE
Subject:
M.I.L. "ON" DTC P0770
Some owners of 2002 model year 4Runner vehicles and and Tacoma vehicles equipped with V6 engines and automatic transmissions may experience a M.I.L. "ON" condition with DTC P0770 (Shift Solenoid "E" Malfunction) stored when operated under the following specific operating conditions:
- Operation in ambient temperatures above 32°C or 90°F.
- When towing a trailer or carrying a heavy load.
- When climbing a long uphill grade.
The ECM logic (SAE term: Powertrain Control Module/PCM) has been revised and the transmission valve body has been improved to prevent this condition from occurring.
APPLICABLE VEHICLES:
- 2002 model year 4Runner vehicles produced BEFORE the Production Change Effective VIN shown below.
- 2002 model year Tacoma vehicles equipped with V6 engines and automatic transmissions produced BEFORE the Production Change Effective VIN shown below.
PRODUCTION CHANGE INFORMATION:
PARTS INFORMATION:
CALIBRATION INFORMATION:
REQUIRED TOOLS & MATERIAL:
REPAIR PROCEDURE:
Verify Vehicle Condition
Step 1. Did M.I.L. "ON" DTC P0770 occur under any one of the following conditions?
a) Operation of vehicle in ambient temperatures above 32°C or 90°F.
b) While towing or carrying a heavy load.
c) While climbing a long uphill grade.
If YES - proceed to Step 2.
If NO - TSB does not apply - refer to ETAS or 2002 Repair Manual DTC P0770 Diagnostic for Chart to repair vehicle.
Step 2. Check for Authorized Modifications label affixed to the vehicle in the location shown in Figure 1. Confirm if ECM (PCM) calibration has been updated.
If no label or label does not list the "New Calibration ID Number" listed above - Proceed to Step 3.
Step 3. Connect the Diagnostic Tester to the vehicle and select CURRENT ECU CAL from the ECU REPROGRAM MAIN MENU. Determine the vehicle's current ECU calibration (see Figure 2).
NOTE:
- If Calibration ID matches "Previous Calibration ID" as shown, proceed with flash reprogramming.
- If Calibration ID matches "New Calibration ID" as shown, this vehicle has already been reprogrammed. Refer to Repair Manual for diagnosis.
Step 4.
If ECU calibration ID is not "New Calibration ID" proceed to Step 5.
If ECU calibration ID is "New Calibration ID," refer to ETAS or appropriate 2002 Repair Manual DTC P0770 Diagnostic Chart to repair vehicle.
Step 5. Perform Active Test of lockup Solenoid (SL Solenoid or Solenoid "E") using Diagnostic Tester.
a) Set up Diagnostic Tester (see Figure 1).
b) Drive vehicle to a speed above 64 km/h or 40 mph.
c) Maintain constant throttle input and speed while using Active Test of SL Solenoid on Diagnostic Tester (see Figure 2).
d) When SL Solenoid is turned "ON" torque converter should lock up within 5 seconds and engine rpm should drop 100-200 rpm.
e) When SL Solenoid is turned "OFF" engine rpm should rise 100-200 rpm within 5 seconds.
f) Repeat several times to confirm proper operation of SL Solenoid/torque converter.
If SL Solenoid operation/torque converter lockup operation is normal - Proceed To 6.
If SL Solenoid operation/torque converter lockup does not occur, takes excessive time, or rpm drop is insufficient - Follow diagnostics on ETAS for DTC P0770 or 2002 Repair Manual. Once converter lockup is repaired to normal operation - Proceed To 6.
Step 6. Proceed to Flash Reprogram ECM (PCM).
Flash Reprogram ECM (PCM)
1. 4Runner only: Remove the ABS1 and ABS2 fuses from Engine Room Junction Block (see Figure 5.)
2. Follow the procedures outlined in TSB # 1204, Ref.# GI-03-007 ECU Flash Reprogramming Process," and flash the ECM (PCM) with the new calibration file update.
3. Enter the required information on the Authorized Modifications Label and affix it to the vehicle at the location shown in Figure 1. The Authorized Modifications Label is available through the PDC, P/N 00451-00001-25.
3. Enter the required information on the Authorized Modifications Label and affix it to the vehicle at the location shown in Figure 1. The Authorized Modifications Label is available through the PDC, P/N 00451-00001-25.
4. 4Runner only: Reinstall the ABS1 and ABS2 fuses (Figure 5.)
5. Use the Diagnostic Tester to delete any ABS/VSC DTCs that may have been set during this repair procedure.
6. Calibration update is complete.
Valve Body Replacement
1. Replace valve body assembly per ETAS or applicable Repair Manual (2002 Tacoma, Volume 2, Automatic Transmission [A340E, A340F] or 2002 4Runner, Volume 2, Automatic Transmission).
2. Reset the ECM (PCM) learned and memory values. Refer to the procedures (Figure 6).
3. Start the engine and warm it up to normal operating temperature before test-driving.
NOTE:
The effect of the new calibration may become more apparent after several days of driving as the ECM (PCM) "learned values" are re-established from the customer's driving.
4. Test drive and confirm lockup operation and no recurrence of DTC P0770.
REPAIR TIME:
NOTE:
Issue of this Technical Service Bulletin is to ensure that proper repair information is available. IT DOES NOT CONSTITUTE AN AUTHORIZATION FOR REPAIR. Normal provisions of the formal warranty policy, as applicable, will apply.