Troubleshooting the DFI System
When checking a harness [A] for short circuit, open one
end [B] and check the continuity between the other end
[C] and ground [D]. If there is continuity, the harness has
a short circuit to ground, and it must be repaired or re-
Narrow down suspicious locations by repeating the con-
tinuity tests from the ECU connectors.
If no abnormality is found in the wiring or connectors, the
DFI parts are the next likely suspects. Check the part,
starting with input and output voltages. However, there is
no way to check the ECU itself.
If an abnormality is found, replace the affected DFI part.
If no abnormality is found in the wiring, connectors, and
DFI parts, replace the ECU.
FUEL SYSTEM (DFI) 3-21