F5
UnclassifiedLubrication
What This Code Means
No voltage measured at pin 3O on the ECM connector; ECM firmware version reads unknown; No voltage measured in Step 11 (of a procedure not fully detailed); Steps 4 and 6 tested good (of a procedure not fully detailed); Step 14 tested bad (of a procedure not fully detailed); Step 14 tested good (of a procedure not fully detailed); CAN bus communication failure between ECM and controller; Wire 608 to ground has low resistance on the coil of the relay.; Wire 14F to ground shows DC battery voltage.; Wire 13 has no or low battery voltage at the relay.
Possible Causes
- •Blown in-line 15-amp fuse in the harness
- •Faulty Wire 601 between the controller and the low fuel pressure switch
- •Faulty printed circuit board
- •Issue with CAN bus communication lines (Wires 743a and 744a)
- •Issue with termination resistors
- •Issue with wiring harness continuity
- •Faulty F5 fuse
- •Break in the wire between the relay and the battery
Suggested Actions
- 1Check the in-line 15-amp fuse in the harness (located roughly 6 inches from the starter) and repair as needed.
- 2Repair or replace Wire 601 between the controller and the low fuel pressure switch.
- 3Replace printed circuit board.
- 4Check firmware for updates.
- 5Check for battery voltage at pin 3O on the ECM connector.
- 6Check the in-line 15-amp fuse in the harness.
- 7Check for battery voltage at pin 2O on the ECM connector (Wire 172) while pressing manual start.
- 8Replace F5 fuse
- 9Test the harness back toward the battery looking for a break in the wire.
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