If a malfunction is detected in the starter circuit, the engine stop and start ECU stores DTC P164400 and blinks the stop and start cancel indicator.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Warning Indicate | Note |
|---|---|---|---|---|---|
| P164400 | ECU Internal Error | Both of the following conditions are met for 0.2 seconds or more (1 trip detection logic):
·
Ignition switch ON. ·
Malfunction in starter circuit (STA). |
·
Wire harness or connector ·
ST relay ·
Engine stop and start ECU |
Blinks | SAE Code: P1644 |
CONFIRMATION AFTER TROUBLESHOOTING
If the cable is disconnected from the auxiliary battery terminal, stop and start control is prohibited until refresh charge is completed.
In this case, let the vehicle idle to complete the refresh charge. The refresh charge is complete when the Data List item Status of Battery Charge Control changes from "Refresh Charge Mode". (Usually, idling the engine for 5 to 60 minutes with the auxiliary battery fluid temperature at 11°C (52°F) or higher, the refresh charge will be completed.)
If the GTS is not available and the Data List item Status of Battery Charge Control cannot be checked, charge the auxiliary battery by idling the engine for approximately 5 to 60 minutes or driving the vehicle, and then drive the vehicle and check that stop and start control operates.
If the engine is started with the hood open, the system determines that a jump start has occurred. Therefore, make sure that the hood is closed before starting the engine and driving the vehicle.
After the refresh charge completes, turn the ignition switch off, wait for at least 30 seconds, and then start the engine again. If the vehicle enters refresh charge mode again while the engine is idling, the initial refresh charge did not properly complete, so wait for the refresh charge to complete.
Allow the engine to idle for 3 minutes after it is warmed up and check that the engine idle speed is within 50 rpm of the target idle speed.
Clear the DTCs.
Start the engine and warm it up.
Drive the vehicle at 7 km/h (4 mph) or more.
When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.
Depress the brake pedal and stop the vehicle.
Keep the engine stopped by stop and start control for 1 second or more. (Keep the shift lever in D.)
Release the brake pedal with the shift lever in D to start the engine.
Check that DTCs are not output.
STOP AND START SYSTEM OPERATION CHECK
Refer to DTC P061519.
Before replacing the engine stop and start ECU, read the number of starter operations and write it into a new engine stop and start ECU.
After replacing the engine stop and start ECU, perform learning of the external backup boost converter (eco run vehicle converter assembly).
After replacing the engine stop and start ECU or air conditioning amplifier assembly, reset and perform learning of the air conditioning information in the engine stop and start ECU.
Inspect the fuses for circuits related to this system before performing the following procedure.
Using the GTS, read the freeze frame data before troubleshooting. System condition information is recorded as freeze frame data the moment a DTC is stored. This information can be useful when troubleshooting.
If DTCs P060B1C (Analog to Digital Converter Circuit Voltage Out of Range), P060B49 (Analog to Digital Converter Internal Electronic Failure) or P060B71 (Analog to Digital Converter Actuator Stuck) and P164400 (ECU Internal Error) are output simultaneously, perform troubleshooting for DTC P060B1C, P060B49 or P060B71 first as it may have caused DTC P164400 to be stored.
If DTCs P061519 (Starter Relay Circuit Current Above Threshold) and P164400 (ECU Internal Error) are output simultaneously, perform troubleshooting for DTC P061519 first as it may have caused DTC P164400 to be stored.
For wire harness and connector inspection procedures and precautions, refer to "General>INTRODUCTION>HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS>ELECTRONIC CIRCUIT INSPECTION PROCEDURE202201,999999,_V1,_107171,_0496334,RM100000001YK2F,"
DTCs for the stop and start system are not cleared even if the malfunction has been repaired. After repairing the malfunction, be sure to clear the DTCs.
Read the DTCs.
| Result | Proceed to |
|---|---|
| DTC P164400 is output | A |
| DTCs P060B1C, P060B49 or P060B71 and P164400 are output | B |
| DTCs P061519 and P164400 are output | C |
A
B
C
Disconnect the I223 certification ECU (smart key ECU assembly) connector.*1
*1: w/ Smart Entry and Start System
Disconnect the I12 ignition or starter switch assembly connector.*1
*1: w/o Smart Entry and Start System
Disconnect the C62 park/neutral position switch assembly connector.
Disconnect the A169 engine stop and start ECU connector.
Remove the ST relay from the No. 1 engine room relay block.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| A169-21 (STA) - ST relay terminal 2 | Always | Below 1 Ω |
| A169-21 (STA) - Body ground and other terminals | Always | 10 kΩ or higher |
| ST relay terminal 2 - Body ground and other terminals | Always | 10 kΩ or higher |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Disconnect the A169 engine stop and start ECU connector.
Disconnect the C62 park/neutral position switch assembly connector.
Disconnect the I223 certification ECU (smart key ECU assembly) connector.*1
*1: w/ Smart Entry and Start System
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| A169-21 (STA) - C62-5 (L) | Always | Below 1 Ω |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Remove the ST relay from the No. 1 engine room relay block.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| ST relay terminal 1 - Body ground | Always | Below 1 Ω |
| Proceed to |
|---|
| OK |
| NG |
OK
NG