DESCRIPTION
While the engine is being cranked, a starter operation request signal is sent to terminal STA of the ECM.
Tech Tips
If there is an open in the STA circuit of the ECM, stop and start control will be prohibited after the third time the engine is started by stop and start control.
Stop and start control will be prohibited until the ignition switch is turned off.
The MIL will not illuminate.
If there is an open in the STA circuit of the ECM, the engine can still be started using the ignition or starter switch assembly*1 or push start switch assembly*2 , as the ECM also receives the starter operation request signal from the engine stop and start ECU via CAN communication. (Stop and start control is prohibited as the reliability of the signal sent via CAN communication cannot be assured while the voltage drops during operation of the starter assembly.)
*1: w/o Entry and Start System
*2: w/ Entry and Start System
WIRING DIAGRAM
PROCEDURE
READ VALUE USING GTS (STARTER SIGNAL)
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Starter Signal.
| Tester Display |
|---|
| Starter Signal |
Read the values displayed on the GTS when the ignition switch is ON and to START.
| OK | ||||||||
|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| NG |
|
CHECK HARNESS AND CONNECTOR (ECM - ST RELAY)
Disconnect the A62 ECM connector.
Remove the ST relay from the No. 2 engine room relay block and junction block assembly.
Disconnect the A66 engine stop and start ECU connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |