Diagnosis Procedure
Regarding Wiring Diagram information, refer to BCS "Wiring Diagram".
1.CHECK FUSES AND FUSIBLE LINK
Is the fuse blown?
YES >> Replace the blown fuse or fusible link after repairing the affected circuit.
NO >> GO TO 2.
2.CHECK POWER SUPPLY CIRCUIT
1. Disconnect BCM connector M99.
2. Check voltage between BCM connector M99 and ground. 
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair harness or connector.
3.CHECK GROUND CIRCUIT
Check continuity between BCM connector M99 and ground.
Is the inspection result normal?
YES >> Inspection End.
NO >> Repair harness or connector.

Diagnosis Procedure Regarding Wiring Diagram information, refer to BCS "Wiring Diagram". 1.CHECK INPUT 1 - 5 CIRCUIT FOR OPEN 1. Turn ignition switch OFF. 2. Disconnect BCM and combinati ...
Ignition timing
Inspection
1.CHECK IGNITION TIMING
1. Attach timing light (A) to loop wire (1) as
shown.
2. Check ignition timing.
1 : Timing indicator
>> INSPECTION END
...
U0073 Communication bus a off
DTC Logic
DTC
Trouble diagnosis name
DTC detecting condition
Possible causes
U0073
Control Module Communication
Bus "A" Off
When the ignition switch is ON,
TCM detects a bus-off error
continuously for 2 seconds or
more.
Harness or connector
(CA ...