TROUBLESHOOTING
Troubleshooting by DTC Fault Codes
13-76
6LY3 Service Manual
© 2007 Yanmar Marine International
DTC Fault Code
Fault
Troubleshooting Procedure
1. Check if the i2 module unit is working.
2. Check the CAN communication cable between ECU and i2 module.
3. Check if the 8320 is installed. Check for proper software and software settings.
DTC / FMI
1. Condition, 2. Fault, 3. Time to Detect, 4. Display
Check Point
U0146/12
1. Key switch ON
2. No throttle position data transmitted from i2 module (i83XX)
3. 1 second
4. ENG COM ERROR on the TELEFLEX display
Wire harness (CAN
communication cable)
i2 module
Wire harness
Fail Mode
ECU receives the throttle position data from the i2 module (i832X) and then goes to the throttle
failure code if it loses i2 module communication. Target engine speed slows to low idle speed
and stays there until the sub-throttle is activated. Sub-throttle will be selectable with the
sub-throttle lamp blinking. If the sub-throttle is selected, the lamp turns on. Once the sub-throttle
is selected, the sub-throttle keeps working even if the i2 module communication would go back
to normal.
Limited Operation
Main throttle fail mode
Fail Release
Yes (i2 module communication error)
Limited Operation Release
Main throttle fail release
1. If the sub-throttle is active: No.
2. If the sub-throttle is inactive: Yes.
After the U0146 failure is cleared
Remarks
This DTC comes from communication between i2 module and ECU only. A TELEFLEX control
head malfunction will be detected as “Main Throttle Position Sensor Error.”
Marine gear transmission control (shift) function is independent of the throttle function. This
means that the shifting function should be controlled as an i2 module function. (If i2 module is
OFF, then a U0146 failure code occurs and the shift function may go inactive.)
If the sub-throttle is selected before communication goes back to normal, the main throttle will
stay inactive.
DTC / FMI
Probable Cause
U0146/12
1. Wire harness (CAN) between ECU and Teleflex i2 module is open or the connector is not connected properly.
2. i2 module powered off or has a malfunction.