STOP AND START SYSTEM, Diagnostic DTC:P1780
| DTC Code | DTC Name |
|---|---|
| P1780 | Discrepancy between Neutral Position SW and Shift Position |
DESCRIPTION
The engine stop and start ECU detects a malfunction by comparing the shift position signal with the neutral position switch signal input state. When a malfunction occurs, the engine stop and start ECU stores this DTC, blinks the stop and start cancel indicator light, and prohibits the stop and start control.
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
Warning Indicate |
Memory |
|---|---|---|---|---|---|
P1780 |
Discrepancy between Neutral Position SW and Shift Position |
The following condition continues for 1 seconds or more (1 trip detection logic):
|
|
Blinking |
DTC stored |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
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 or air conditioning amplifier assembly, reset and perform learning of the air conditioning information in the engine stop and start ECU.
After replacing the engine stop and start ECU or airbag sensor assembly, clear and calibrate the deceleration sensor zero point in the engine stop and start ECU.
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.
PROCEDURE
READ VALUE USING GTS (NEUTRAL SWITCH)
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Stop and Start / Data List / Neutral Switch.
Powertrain > Stop and Start > Data List
Tester Display
Neutral Switch
Read the value when the shift lever is in neutral and any other position
OK
Tester Display
Condition
Normal Condition
Neutral Switch
Shift lever in neutral
ON
Shift lever in any position other than neutral
OFF
Result
Result
Proceed to
NG
A
OK
B
CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - NEUTRAL POSITION SWITCH)
Disconnect the A9 engine stop and start ECU connector.
Disconnect the B100 neutral position switch connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
A9-26 (TMVC) - B100-1 (WI)
Always
Below 1 Ω
A9-25 (TME2) - B100-3 (F+)
Always
Below 1 Ω
A9-27 (TMN) - B100-2 (TMN)
Always
Below 1 Ω
A9-26 (TMVC) - Body ground
Always
10 kΩ or higher
B100-1 (WI) - Body ground
Always
10 kΩ or higher
A9-25 (TME2) - Body ground
Always
10 kΩ or higher
B100-3 (F+) - Body ground
Always
10 kΩ or higher
A9-27 (TMN) - Body ground
Always
10 kΩ or higher
B100-2 (TMN) - Body ground
Always
10 kΩ or higher
Result
Proceed to
OK
NG
NG REPAIR OR REPLACE HARNESS OR CONNECTOR
CHECK ENGINE STOP AND START ECU (TMN TERMINAL VOLTAGE)
Measure the voltage according to the value(s) in the table below.
*a
Component with harness connected
(Engine Stop and Start ECU)
-
-
Standard Voltage
Tester Connection
Condition
Specified Condition
A9-27 (TMN) - A9-25 (TME2)
Ignition switch ON, shift lever in neutral
2.7 to 4.3 V
Ignition switch ON, shift lever in any position other than neutral
0.7 to 1.9 V
Result
Result
Proceed to
OK
A
NG (for 1AD-FTV)
B
NG (for 1ND-TV)
C
NG (for 1NR-FE)
D