Toyota Tacoma (2015-2018) Service Manual: All Door Entry Lock/Unlock Functions do not Operate, but Wireless Functions Operate

NOTICE:

• The smart key system (for Entry Function) uses a multiplex communication system (LIN communication system) and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart key system (for Entry Function) after confirming that the communication systems are functioning properly (See page ).
• When using the Techstream with the engine switch off, connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Key. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.
• Check that there are no electrical key transmitter sub-assemblies in the vehicle.
• Before performing the inspection, check that DTC B1242 (wireless door lock control) is not output (See page ).
• Before replacing the certification ECU (smart key ECU assembly), refer to the smart key system (for Entry Function) precaution (See page ).
• After repair, confirm that no DTCs are output by performing the "DTC Output Confirmation Operation".

HINT:

• When the electrical key transmitter sub-assembly is brought near the front door outside handle assembly LH, the possibility of wave interference decreases, and it can be determined if wave interference is causing the problem symptom.
• If the inspection result is that the problem only occurs in certain locations or at certain times of day, the possibility of wave interference is high. Also, added vehicle components may cause wave interference. If installed, remove them and perform the operation check.
• There may be wave interference if the vehicle is near broadcasting antennas, large video displays, wireless garage door opener systems, wireless security cameras, home security systems, etc. In this case, move the vehicle to a different location and check if there is any improvement.
• If a tool for checking radio waves, such as a signal strength meter, is available, move around the area while observing both the LF band (used by the vehicle antenna to form the detection area) and RF band (used by the electrical key transmitter sub-assembly for transmission) to check for locations where there is wave interference.
• The transmitting wave of the wireless function and entry function are the same, but the wave logic is different. As a result, it is possible that only the wireless function or only the entry function is affected by wave interference.