All Door Entry Lock/Unlock Functions and Wireless Functions Do Not Operate

THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Entry Function): All Door Entry Lock/Unlock Functions and Wireless Functions do not Operate
- All Door Entry Lock/Unlock Functions and Wireless Functions do not Operate

DESCRIPTION

When the entry operation and wireless operation of the door lock functions do not operate, a malfunction or wave interference may be occurring in either of the following: 1) the signal communication line between the door control receiver and certification ECU (smart key ECU assembly) (the line used for entry and wireless operations); or 2) the electrical key transmitter. If the entry lock and wireless lock operations cannot be performed, there may be electrical key transmitter malfunctions, wave interference or problems in the communication which is used for the entry and wireless function between the door control receiver and certification ECU (smart key ECU assembly).

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:
* The smart key system (for Entry Function) uses the CAN communication system and LIN communication system. First inspect the communication systems by following How to Proceed with Troubleshooting How To Proceed With Troubleshooting. Troubleshoot the smart key system (for Entry Function) after confirming that the communication systems are functioning properly.
* When using the Techstream with the engine switch off to troubleshoot:
Connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds until communication between the Techstream and vehicle begins.
* Check that there are no electrical key transmitters in the vehicle.
* Before performing the inspection, check that DTC B1242 (wireless door lock control) is not output Smart Key System (for Entry Function).
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.
* When checking the entry lock operation multiple times, the lock operation may be limited to 2 consecutive operations depending on the settings. In order to perform the entry lock operation 3 or more times, an unlock operation must be performed once (any type of unlock operation is sufficient). However, only consecutive entry lock operations are limited. Using the wireless lock or other types of lock operations, it is possible to perform consecutive lock operations without this limitation.
* Before replacing the certification ECU (smart key ECU assembly), refer to the smart key system (for Entry Function) Smart Key System (for Entry Function).
* The door control receiver has a constant voltage (5 V) supply circuit connected to terminal "+5".

PROCEDURE

1. INSPECT BATTERY VOLTAGE

(a) Measure the voltage of the battery.

Standard voltage:

11 to 14 V

HINT
It may be possible to tell whether the battery is depleted by operating the horn.

If the voltage is below 11 V, recharge or replace the battery before proceeding.

NEXT -- Continue to next step.

2. CHECK FOR DTC

(a) Open the driver side door using the mechanical key built into the electrical key transmitter.

(b) Connect the Techstream and check for DTCs Smart Key System (for Entry Function).

HINT
When using the Techstream with the engine switch off to troubleshoot: Connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds until communication between the Techstream and vehicle begins.

OK:

DTC is not output.

NG -- Go to DIAGNOSTIC TROUBLE CODE CHART Smart Key System (for Entry Function)
OK -- Continue to next step.

3. CHECK POWER DOOR LOCK CONTROL SYSTEM

(a) When the door control switch on the power window regulator master switch assembly on the driver side door is operated, check that the doors unlock and lock according to the switch operation Operation Check.

OK:

Door locks operate normally.

NG -- Go to POWER DOOR LOCK CONTROL SYSTEM Problem Symptoms Table
OK -- Continue to next step.

4. CHECK ELECTRICAL KEY TRANSMITTER

(a) When another registered electrical key transmitter is used, check that the wireless and entry functions operate normally Operation Check.

Result

B -- CHECK WAVE ENVIRONMENT
A -- Continue to next step.

5. CHECK ELECTRICAL KEY TRANSMITTER (LED)

(a) Press and hold the lock switch of the transmitter for 5 seconds and check the number of times that the transmitter LED illuminates.

Result

HINT
* The electrical key transmitter sends voltage information to the certification ECU (smart key ECU assembly) when it is being used. The certification ECU (smart key ECU assembly) displays "Yes" for the "Key Low Battery" item of the Data List when this voltage information indicates 2.1 V or less Smart Key System (for Entry Function).
* Even if the transmitter battery is depleted, it is still possible to start the engine by holding the electrical key transmitter against the engine switch, depressing the brake pedal*1 or clutch pedal*2 and pressing the engine switch.
* *1: for Automatic Transaxle
* *2: for Manual Transaxle

C -- REPLACE TRANSMITTER BATTERY Transmitter Battery (w/ Smart Key System)

B -- REPLACE ELECTRICAL KEY TRANSMITTER
A -- Continue to next step.

6. INSPECT TRANSMITTER BATTERY (VOLTAGE)

(a) Remove the transmitter battery from the electrical key transmitter that does not operate Transmitter Battery (w/ Smart Key System).

(b) Attach a lead wire (0.60 mm [0.027 in.] in diameter or less including wire sheath) with tape or equivalent to the negative terminal.

Text in Illustration

NOTICE:
Do not wrap the lead wire around a terminal, wedge it between terminals, or solder it. The terminal may be deformed or damaged, and the battery will not be able to be installed correctly.

(c) Carefully pull the lead wire out from the position shown in the illustration and install the previously removed transmitter battery.

(d) Measure the voltage of the transmitter battery.

HINT
* When measuring the battery voltage, bring the electrical key transmitter within the entry lock operating range while operating the lock sensor of a door handle to perform the measurement. For the entry lock operating range, refer to System Description Smart Key System (for Entry Function).
* Perform the measurement when the electrical key transmitter is at room temperature.
* The electrical key transmitter sends voltage information to the certification ECU (smart key ECU assembly) when it is transmitting. When this voltage is 2.1 V or less, the Data List item "Key Low Battery" displays "Yes".

Standard Voltage:

NG -- REPLACE TRANSMITTER BATTERY Transmitter Battery (w/ Smart Key System)

OK -- REPLACE ELECTRICAL KEY TRANSMITTER

7. CHECK WAVE ENVIRONMENT

(a) Bring the electrical key transmitter near the door control receiver and perform a wireless and entry function operation check.

HINT
* When the electrical key transmitter is brought near the door control receiver, the possibility of electric wave interference decreases, and it can be determined if electric wave interference is causing the problem.
* 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 added vehicle components are installed, remove them and perform the operation check.
* There may be electric 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 electric 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 key detection area) and RF band (used by the electrical key transmitter for transmission) to check for locations where there is wave interference.

OK:

Wireless and entry functions operate normally.

NG -- CHECK POWER SOURCE

OK -- AFFECTED BY WAVE INTERFERENCE

8. CHECK POWER SOURCE

(a) When the power source mode is off, check that the functions other than the entry functions recognize the power source mode as being off.

HINT
* Check if systems that should not be operating when the power source mode is off are operating.
* When the certification ECU (smart key ECU assembly) mistakenly determines the power source mode to be on (IG) for some reason [example: an ECU mistakenly determines the power source mode to be on (IG) and sends that information to the certification ECU (smart key ECU assembly)] even though the power source mode is off, the certification ECU (smart key ECU assembly) stops the entry and wireless functions.

OK:

When the power source mode is off, functions other than the entry functions recognize the power source mode as being off.

NG -- Go to SMART KEY SYSTEM (FOR START FUNCTION) Problem Symptoms Table
OK -- Continue to next step.

9. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - BATTERY AND BODY GROUND)

(a) Disconnect the C35 certification ECU (smart key ECU assembly) connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Text in Illustration

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

10. CHECK HARNESS AND CONNECTOR (DOOR CONTROL RECEIVER - CERTIFICATION ECU AND BODY GROUND)

(a) Disconnect the H19 door control receiver connector.

(b) Disconnect the C36 certification ECU (smart key ECU assembly) connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

HINT
For the waveforms between the certification ECU (smart key ECU assembly) and door control receiver when the electrical key transmitter is operated, refer to Terminals of ECU Smart Key System (for Entry Function).

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

11. REPLACE DOOR CONTROL RECEIVER (OPERATION)

(a) Temporarily replace the door control receiver with a new or normally functioning one Removal.

NEXT -- Continue to next step.

12. CHECK WIRELESS AND ENTRY FUNCTION

(a) Check that the wireless and entry functions operate normally.

OK:

Wireless and entry functions operate normally.

NG -- REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Removal

OK -- END (DOOR CONTROL RECEIVER IS DEFECTIVE)