FAILURE DIAGNOSIS
1-124
TNV DI Service Manual
DTCs (Diagnostic Trouble Codes) General Description
(3) P0686/4: Main relay error
DTC Detecting Conditions
Movement at Error occurrence
Estimation of Failure cause/Error condition
• The connector may not be properly connected.
• Wiring defect of the harness
•
Downstream line of the main relay coil may be short-circuited with GND or POWER SUPPLY (*NOTE).
• The main relay contact may be faulty.
•
The main relay contact may be stuck.
•
Inner wiring of the main relay coil short-circuited with POWER SUPPLY (*NOTE).
*NOTE) If the downstream line of the main relay coil is short-circuited with POWER SUPPLY, the E-ECU's
power supply line fuse 10A may be blown or the inner circuit of E-ECU may fail.In this case, the E-
ECU may fail to detect/indicate the error, and to store the error history.
• The E-ECU internal circuitry may be faulty.
DTC
P0686/4
Main relay error
1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indicator
Check points
1. Key switch OFF.
2. Power supply to ECU fails to turn OFF.
3. One flash followed by six flashes.
Connector
Harness
Main relay
Error Mode
[Run As Is]:
After detecting the error, the system lets the engine continue to run without any
restrictions.
Run restricted?
No.
Recovery
Conditions
No.
Remarks
TNV_DI_SM_A4-Troubleshooting.book 124 ページ ２００７年１１月１５日 木曜日 午後５時２７分
