Diagnosis Procedure

WARNING: This page is about a different variant/trim than selected.

Regarding Wiring Diagram information, refer to [TRANSFER CONTROL UNIT: WIRING DIAGRAM ].

DIAGNOSIS PROCEDURE

Step	Action	YES	NO
1	CHECK POWER SUPPLY Turn ignition switch "OFF". (Stay for at least 5 seconds.) Disconnect transfer control unit harness connector. Check voltage between transfer control unit harness connector terminals and ground. Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP. Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP. 4. Turn ignition switch "ON". (Do not start engine.) Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP. 5. Check voltage between transfer control unit harness connector terminals and ground. Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP. Is there voltage?	GO TO 2.	Check the following. If any items are damaged, repair or replace damaged parts. 40A fuse (No. J , located in the fuse and fusible link box). 10A fuses (No. 21, located in the fuse block (J/B) and Nos. 57 and 58 located in the fuse and relay box). Harness for short or open between battery and transfer control unit harness connector M152 terminal 19. Harness for short or open between battery and transfer shut off relay 2 harness connector E157 terminal 1 and 3. Harness for short or open between battery and transfer shut off relay 1 harness connector E156 terminal 3. Harness for short or open between ignition switch and transfer control unit harness connector M152 terminal 25. Harness for short or open between ignition switch and transfer shut off relay 1 harness connector E156 terminal 1. Harness for short or open between transfer shut off relay 2 harness connector E157 terminal 5 and transfer control unit harness connector M153 terminals 44, 45. Harness for short or open between transfer shut off relay 1 harness connector E156 terminal 5 and transfer control unit harness connector M153 terminals 44, 45. Harness for short or open between transfer shut off relay 2 harness connector E157 terminal 2 and transfer control unit harness connector M153 terminal 40. Harness for open between transfer shut off relay 1 harness connector E156 terminal 2 and ground. Battery and ignition switch. Transfer shut off relay 1, 2. Refer to [P1801, P1811 POWER SUPPLY CIRCUIT FOR TRANSFER CONTROL UNIT ].
2	CHECK GROUND CIRCUIT Turn ignition switch "OFF". Disconnect transfer control unit harness connector. Check continuity between transfer control unit harness connector M152 terminals 6 (M/T models) and 18, and M153 terminal 32 and ground. Courtesy of SUZUKI OF AMERICA CORP. Continuity should exist. Also check harness for short to power. Do you have continuity?	GO TO 3.	Repair open circuit or short to power in harness or connectors.
3	CHECK TRANSFER CONTROL UNIT Check transfer control unit input/output signal. Refer to [TRANSFER CONTROL UNIT: REFERENCE VALUE ]. Are the inspection results normal?	GO TO 4.	Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
4	CHECK DTC Drive vehicle and then perform "DTC check". Do DTC's P1801 or P1811 display?	Replace transfer control unit. Refer to [TRANSFER CONTROL UNIT: REMOVAL AND INSTALLATION ].	Inspection End.