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Problem Symptoms Table

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
ENTRY LOCK / UNLOCK FUNCTION

Symptom Suspected Area Refer to
Entry unlock does not operate. 1. Check for DTCs in the smart key system. Refer to DIAGNOSTIC TROUBLE CODE CHART 
2. Power door lock control system Refer to PROBLEM SYMPTOMS TABLE
3. See "ID code matching inside the cabin cannot be performed" in this table. -
4. Courtesy light switch circuit (Front) Refer to Front Door Courtesy Switch Circuit
5. Courtesy light switch circuit (Rear) Refer to Rear Door Courtesy Switch Circuit
6. Lock position switch circuit (Driver door) Refer to Driver Side Door UNLOCK Detection Switch Circuit
7. Lock position switch circuit (Front passenger door) Refer to Front Passenger Side Door UNLOCK Detection Switch Circuit
8. Lock position switch circuit (Rear passenger door LH) Refer to Rear Door UNLOCK Detection Switch LH Circuit
9. Lock position switch circuit (Rear passenger door RH) Refer to Rear Door UNLOCK Detection Switch RH Circuit
10. Touch sensor circuit Refer to Touch Sensor Circuit
11. Antenna circuit Refer to Antenna Circuit
12. Replace the door oscillator. -
13. Replace the body ECU. -
14. Replace the certification ECU. -
Entry lock does not operate. 1. Check for DTCs in the smart key system. Refer to DIAGNOSTIC TROUBLE CODE CHART 
2. Power door lock control system Refer to PROBLEM SYMPTOMS TABLE
3. See "ID code matching inside the cabin cannot be performed" in this table. -
4. Courtesy light switch circuit (Front) Refer to Front Door Courtesy Switch Circuit
5. Courtesy light switch circuit (Rear) Refer to Rear Door Courtesy Switch Circuit
6. Lock position switch circuit (Driver door) Refer to Driver Side Door UNLOCK Detection Switch Circuit
7. Lock position switch circuit (Front passenger door) Refer to Front Passenger Side Door UNLOCK Detection Switch Circuit
8. Lock position switch circuit (Rear passenger door LH) Refer to Rear Door UNLOCK Detection Switch LH Circuit
9. Lock position switch circuit (Rear passenger door RH) Refer to Rear Door UNLOCK Detection Switch RH Circuit
10. Trigger (Lock) switch circuit Refer to Lock Switch Circuit
11. Antenna circuit Refer to Antenna Circuit
12. Replace the body ECU. -
13. Replace the certification ECU. -
Luggage compartment does not open (when the key is outside the vehicle). 1. Check for DTCs in the smart key system. Refer to DIAGNOSTIC TROUBLE CODE CHART 
2. Power door lock control system Refer to PROBLEM SYMPTOMS TABLE
3. Check if any function is cancelled due to customization. Refer to CUSTOMIZE PARAMETERS 
4. Operate the luggage compartment SW on the key to check the wireless function. (If it does not operate, see "Wireless door lock function" in this table.) -
5. Check operation of the cabin oscillator in diagnostic mode. Refer to DATA LIST / ACTIVE TEST 
6. Luggage oscillator circuit Refer to Luggage Oscillator Circuit
7. Luggage compartment open switch circuit Refer to Luggage Compartment Door Open Switch Circuit
8. Replace the body ECU. -
9. Replace the certification ECU. -
Function to prevent key confinement in the luggage compartment does not operate. (The luggage compartment does not open.) 1. Check for DTCs in the smart key system. Refer to DIAGNOSTIC TROUBLE CODE CHART 
2. Power door lock control system Refer to PROBLEM SYMPTOMS TABLE
3. Courtesy light switch circuit (Front) Refer to Front Door Courtesy Switch Circuit
4. Courtesy light switch circuit (Rear) Refer to Rear Door Courtesy Switch Circuit
5. Lock position switch circuit (Driver door) Refer to Driver Side Door UNLOCK Detection Switch Circuit
6. Lock position switch circuit (Front passenger door) Refer to Front Passenger Side Door UNLOCK Detection Switch Circuit
7. Lock position switch circuit (Rear passenger door LH) Refer to Rear Door UNLOCK Detection Switch LH Circuit
8. Lock position switch circuit (Rear passenger door RH) Refer to Rear Door UNLOCK Detection Switch RH Circuit
9. Check if any function is not cancelled due to customization. Refer to CUSTOMIZE PARAMETERS 
10. Operate the LOCK/UNLOCK SW on the key to check the wireless function. (If it does not operate, see "Wireless door lock function" in this table.) -
11. Check operation of the cabin oscillator in diagnostic mode. Refer to DATA LIST / ACTIVE TEST 
12. Luggage oscillator circuit Refer to Luggage Oscillator Circuit
13. Replace the body ECU. -
14. Replace the certification ECU. -
Function to prevent key confinement in the luggage compartment does not operate. (The alarm does not sound.) 1. Check if the function to prevent key confinement in the luggage compartment operates. -
2. Check if answer back is performed when the wireless door lock is operated. Refer to OPERATION CHECK
3. Replace the certification ECU. -
The outside alarm of the answer back and entry systems does not sound. 1. Check if the function to prevent key confinement in the luggage compartment operates. -
2. Check that "WIRLS BUZZ RESP" and "HAZARD ANS BACK" in the DATA LIST of the body ECU is YES. (If it is NO, go to POWER DOOR LOCK CONTROL SYSTEM power door lock system.) Refer to DATA LIST / ACTIVE TEST
3. Wireless door lock tuner circuit (DTC B1242) Refer to DTC B1242: Wireless Door Lock Tuner Circuit Malfunction
4. Replace the certification ECU. -
The inside alarm of the entry system does not sound. 1. Operate the LOCK/UNLOCK SW on the key to check the wireless function. (If it does not operate, see "Wireless door lock function" in this table.) -
2. Check if the key reminder buzzer sounds. -
3. Replace the certification ECU. -
ID code matching inside the cabin cannot be performed. 1. Check if any function is cancelled due to customization. Refer to CUSTOMIZE PARAMETERS 
2. Operate the LOCK/UNLOCK SW on the key to check the wireless function. (If it does not operate, see "Wireless door lock function" in this table.) -
3. Check the cabin oscillator operation in the diagnostic mode. Refer to DATA LIST / ACTIVE TEST 
4. Cabin oscillator circuit Refer to Room Oscillator Circuit
5. Luggage oscillator circuit Refer to Luggage Oscillator Circuit
6. System is normal. -
ID code matching outside the cabin cannot be performed. 1. Check if any function is cancelled due to customization. Refer to CUSTOMIZE PARAMETERS 
2. Operate the LOCK/UNLOCK SW on the key to check the wireless function. (If it does not operate, see "Wireless door lock function" in this table.) -
3. Check operation of each door oscillator in diagnostic mode. Refer to DATA LIST / ACTIVE TEST 
4. Door oscillator circuit Refer to Door Oscillator Circuit
5. System is normal. -
WIRELESS DOOR LOCK FUNCTION

Symptom Suspected Area Refer to
Wireless door lock function does not operate. 1. Key Refer to INSPECTION
2. Wireless door lock tuner circuit (DTC B1242) Refer to DTC B1242: Wireless Door Lock Tuner Circuit Malfunction
3. Power door lock control system Refer to PROBLEM SYMPTOMS TABLE
4. Replace the certification ECU. -
Luggage compartment is the only wireless door lock function that does not operate. 1. Key Refer to INSPECTION
2. Wireless door lock tuner circuit (DTC B1242) Refer to DTC B1242: Wireless Door Lock Tuner Circuit Malfunction
3. Power door lock control system Refer to PROBLEM SYMPTOMS TABLE
4. Replace the certification ECU -
No answer back (wireless door lock buzzer) 1. Lock position switch circuit (Driver door) Refer to Driver Side Door UNLOCK Detection Switch Circuit
2. Lock position switch circuit (Front passenger door) Refer to Front Passenger Side Door UNLOCK Detection Switch Circuit
3. Lock position switch circuit (Rear passenger door LH) Refer to Rear Door UNLOCK Detection Switch LH Circuit
4. Lock position switch circuit (Rear passenger door RH) Refer to Rear Door UNLOCK Detection Switch RH Circuit
5. Wireless door lock buzzer circuit Refer to Wireless Door Lock Buzzer Circuit
6. Replace the certification ECU. -
No answer back (hazard warning light) 1. Lock position switch circuit (Driver door) Refer to Driver Side Door UNLOCK Detection Switch Circuit
2. Lock position switch circuit (Front passenger door) Refer to Front Passenger Side Door UNLOCK Detection Switch Circuit
3. Lock position switch circuit (Rear passenger door LH) Refer to Rear Door UNLOCK Detection Switch LH Circuit
4. Lock position switch circuit (Rear passenger door RH) Refer to Rear Door UNLOCK Detection Switch RH Circuit
5. Turn signal warning light circuit Refer to Hazard Warning Light Circuit
6. Replace the certification ECU. -
STEERING LOCK FUNCTION

Symptom Suspected Area Refer to
Steering wheel cannot be unlocked (the engine cannot be started). 1. Check for DTCs in the push button start. Refer to DIAGNOSTIC TROUBLE CODE CHART
2. Check for DTCs in the smart key system. Refer to DIAGNOSTIC TROUBLE CODE CHART 
3. Check that the "LCK/UNLCK REC" item in the DATA LIST of the certification ECU displays YES within 10 seconds after starting the engine. (If it displays NO, see "No steering unlock command" in this table.) -
4. Check the output from the IGE terminal of the steering lock ECU (DTC B2782). Refer to DTC B2782: Power Source Control ECU Malfunction
5. Steering lock ECU power source circuit Refer to Power Source Circuit
6. Replace the steering lock ECU. -
Steering wheel cannot be unlocked (no steering unlock command). 1. Check that the "S CODE MACH" item in the DATA LIST of the certification ECU displays OK. (If it displays NG, replace the certification ECU or ID code box.) Refer to DATA LIST / ACTIVE TEST 
2. Check that the "L CODE MACH" item in the DATA LIST of the steering lock ECU displays OK. (If it displays NG, replace the steering lock ECU or ID code box.) Refer to DATA LIST / ACTIVE TEST 
3. Replace the certification ECU. -
Steering wheel cannot be locked. 1. Check for DTCs in the push button start. Refer to DIAGNOSTIC TROUBLE CODE CHART
2. Check for DTCs in the smart key system. Refer to DIAGNOSTIC TROUBLE CODE CHART 
3. With the engine switch OFF and the shift in the P position, open and close the drivers door. After that, check that the "LCK/UNLCK REC" item in the DATA LIST of the certification ECU displays YES within 10 seconds. (If it displays NO, see "No steering lock command" in this table.) -
4. Check the output from the IGE terminal of the steering lock ECU (DTC B2782). Refer to DTC B2782: Power Source Control ECU Malfunction
5. Steering lock ECU power source circuit Refer to Power Source Circuit
6. Replace the steering lock ECU. -
Steering wheel cannot be locked (no steering lock command). 1. Courtesy light switch circuit (Front) Refer to Front Door Courtesy Switch Circuit
2. Courtesy light switch circuit (Rear) Refer to Rear Door Courtesy Switch Circuit
3. Check that the "S CODE MACH" item in the DATA LIST of the certification ECU displays OK. (If it displays NG, replace the certification ECU or ID code box.) Refer to DATA LIST / ACTIVE TEST 
4. Check that the "L CODE MACH" item in the DATA LIST of the certification ECU displays OK. (If it displays NG, replace the steering lock ECU or ID code box.) Refer to DATA LIST / ACTIVE TEST 
5. Replace the certification ECU. -
KEY REMINDER WARNING FUNCTION

Symptom Suspected Area Refer to
Key reminder buzzer does not sound. 1. Perform ACTIVE TEST for the combination meter. Refer to DATA LIST / ACTIVE TEST
2. Check "COURTESY SW" in the DATA LIST of the door lock control system. Refer to DATA LIST / ACTIVE TEST
3. Check the key reminder buzzer when the engine switch is ON (ACC) and the drivers door is opened. -
4. Check if the steering wheel is locked when all power supplies are OFF and the drivers door is opened. (If the steering wheel is not locked, see "Steering wheel cannot be locked" in the steering lock function table.) -
5. Check that the "LCK BAR STUCK" item in the DATA LIST of the certification ECU displays OK. (If it displays NG, replace the steering lock assembly.) Refer to DATA LIST / ACTIVE TEST 
6. Replace the certification ECU. -
PUSH BUTTON START FUNCTION

Symptom Suspected Area Refer to
Engine does not start. 1. Check for DTCs in the push button start. Refer to DIAGNOSTIC TROUBLE CODE CHART
2. Check for DTCs in the smart key system. Refer to DIAGNOSTIC TROUBLE CODE CHART 
3. Check that the engine switch is turned on. -
4. Check cranking operation. (If cranking operation is possible, see "Engine does not start due to the engine immobilizer" in this table.) -
5. Check "SHIFT P SIG" in the DATA LIST of the power source control ECU and confirm that the shift signal is normal. Refer to DATA LIST / ACTIVE TEST 
6. Check whether the steering wheel is locked or unlocked. (If it is locked, see "Steering wheel cannot be unlocked" in the steering lock function table.) -
7. Check the output signal from the ST SW of the certification ECU (DTC B2275). Refer to DTC B2275: STSW Monitor Malfunction
8. Replace the power source control ECU. -
Engine does not start due to the engine immobilizer. 1. Check that the "L CODE MACH" item in the DATA LIST of the certification ECU displays OK. (If it displays NG, replace the steering lock ECU or ID code box.) Refer to DATA LIST / ACTIVE TEST 
2. Check that the "ENG START REQ" item in the DATA LIST of the certification ECU displays YES. (If it displays NO, replace the certification ECU.) Refer to DATA LIST / ACTIVE TEST 
3. Check that the "S CODE MACH" item in the DATA LIST of the certification ECU displays OK. (If it displays NG, replace the certification ECU or ID code box.) Refer to DATA LIST / ACTIVE TEST 
4. Replace the ID code box. -
Engine does not start due to the EFI system. 1. Terminals of ACCR and STAR are turned on when starting the engine (DTC B2276). Refer to DTC B2276: ACCR Signal Circuit Malfunction
2. ST relay Refer to ON-VEHICLE INSPECTION
3. Starter Refer to INSPECTION
4. Replace the ECM. -
Power does not turn on (neither ACC nor IG is possible). 1. Check for DTCs in the push button start. Refer to DIAGNOSTIC TROUBLE CODE CHART
2. Place the key on the drivers seat, move the shift lever to the P position, and depress the brake pedal. Check that the engine switch indicator comes on in green. (If the indicator does not come on or comes on in amber, see "ID code matching inside the cabin cannot be performed" in this table.) -
3. Check the IG1 relay (DTC B2272). Refer to DTC B2272: Ignition 1 Monitor Malfunction
4. Check the IG2 relay (DTC B2273). Refer to DTC B2273: Ignition 2 Monitor Malfunction
5. Check the ACC relay (DTC B2274). Refer to DTC B2274: ACC Monitor Malfunction
6. Check the input terminal of the engine switch (DTC B2278). Refer to DTC B2278: Engine Switch Circuit Malfunction
7. Ground circuit (Power source control ECU - body ground) Refer to TERMINALS OF ECU
8. Replace the power source control ECU. -
Power is not turned on (only ACC is not turned on). 1. Check for DTCs in the push button start. Refer to DIAGNOSTIC TROUBLE CODE CHART
2. Check the ACC relay (DTC B2274). Refer to DTC B2274: ACC Monitor Malfunction
3. Replace the power source control ECU. -
Power is not turned on (only IG is not turned on). 1. Check for DTCs in the push button start. Refer to DIAGNOSTIC TROUBLE CODE CHART
2. Check the IG1 relay (DTC B2272). Refer to DTC B2272: Ignition 1 Monitor Malfunction
3. Check the IG2 relay (DTC B2273). Refer to DTC B2273: Ignition 2 Monitor Malfunction
4. Replace the power source control ECU. -
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