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Diagnosis Procedure

Regarding Wiring Diagram information, refer to INTERIOR ROOM LAMP: WIRING DIAGRAM [WITHOUT POWER DOOR LOCKS] .

CAUTION: Before performing the diagnosis, check that the following is normal.

Fuse
Cargo lamp bulb

DIAGNOSIS PROCEDURE CHART

Step	Action	YES	NO
1	CHECK CARGO LAMP OPERATION Check the cargo lamp operation from the cargo lamp switch, the door switches, and a keyfob (if equipped). Is the cargo lamp inoperative from all of the above switches and the keyfob (if equipped)?	At this time, the cargo lamp operates normally.	Inoperative from all the above switches and the keyfob, GO TO 6 Inoperative from cargo lamp switch only, GO TO 2 Inoperative from door switches only, refer to [DOOR SWITCH CIRCUIT CHECK [KING CAB] ] (king cab), [DOOR SWITCH CIRCUIT CHECK [CREW CAB] ] (crew cab). Inoperative from keyfob only, refer to [KEYFOB BATTERY AND FUNCTION CIRCUIT CHECK ] Fixed ON, GO TO 2
2	CHECK CARGO LAMP SWITCH Check the cargo lamp switch. Refer to [Cargo Lamp Control Circuit Check [with Power Door Locks] ]. Is the inspection result normal?	For inoperative from cargo lamp switch only, GO TO 3 For fixed ON, GO TO 5	Replace the cargo lamp switch.
3	CHECK CARGO LAMP SWITCH CIRCUIT OPEN Disconnect BCM connector M18 and cargo lamp switch connector. 2. Check continuity between BCM connector M18 (A) terminal 31 and cargo lamp switch connector M71 (B) terminal 1. Courtesy of SUZUKI OF AMERICA CORP. Is the inspection result normal?	GO TO 4	Repair harness or connectors.
4	CHECK CARGO LAMP SWITCH GROUND CIRCUIT Check continuity between cargo lamp switch connector M71 terminal 3 and ground. Is the inspection result normal?	Replace BCM. Refer to [BCM (BODY CONTROL MODULE): REMOVAL AND INSTALLATION ]	Repair harness or connectors.
5	CHECK CARGO LAMP SWITCH CIRCUIT SHORT Disconnect BCM connector M18 and cargo lamp switch connector. Check continuity between BCM connector M18 terminal 31 and ground. Courtesy of SUZUKI OF AMERICA CORP.	GO TO 6	Repair harness or connectors.
6	CHECK CARGO LAMP RELAY Check the cargo lamp relay. Refer to [Cargo Lamp Control Circuit Check [with Power Door Locks] ]. Is the inspection result normal?	For fixed OFF, GO TO 7 For fixed ON, GO TO 13	Replace the cargo lamp relay.
7	CHECK CARGO LAMP RELAY CONTROL While operating the cargo lamp switch, check voltage between BCM connector M19 terminal 50 and ground. Is the inspection result normal?	GO TO 8	GO TO 11
8	CHECK CARGO LAMP VOLTAGE Disconnect the cargo lamp connector. While operating the cargo lamp switch, check voltage between cargo lamp connector B161 terminal 3 and ground. Is the inspection result normal?	GO TO 9	GO TO 10
9	CHECK CARGO LAMP GROUND CIRCUIT While operating the cargo lamp switch, check voltage between cargo lamp connector B161 terminal 3 and terminal 2. Is the inspection result normal?	Replace cargo lamp.	Repair harness or connectors.
10	CHECK CARGO LAMP RELAY VOLTAGE PART 1 Check voltage between cargo lamp relay connector M165 terminal 5 and ground. Is the inspection result normal?	Repair harness or connectors between cargo lamp relay and cargo lamp.	Repair harness or connector between splice and cargo lamp relay.
11	CHECK CARGO LAMP RELAY VOLTAGE PART 2 Check voltage between cargo lamp relay connector M165 terminal 2 and ground. Is the inspection result normal?	GO TO 12	Repair harness or connectors.
12	CHECK CARGO LAMP RELAY CONTROL CIRCUIT OPEN Disconnect BCM connector M19 and cargo lamp relay connector. Check continuity between BCM connector M19 (A) terminal 50 and cargo lamp relay connector M165 (B) terminal 1. Courtesy of SUZUKI OF AMERICA CORP. Is the inspection result normal?	Replace BCM. Refer to [BCM (BODY CONTROL MODULE): REMOVAL AND INSTALLATION ]	Repair harness or connectors.
13	CHECK CARGO LAMP RELAY CONTROL CIRCUIT SHORT Disconnect BCM connector M19 and cargo lamp relay. Check continuity between BCM connector M19 terminal 50 and ground. Courtesy of SUZUKI OF AMERICA CORP. Is the inspection result normal?	Replace BCM after making sure the cargo lamp power supply circuit is not shorted to voltage. Refer to [BCM (BODY CONTROL MODULE): REMOVAL AND INSTALLATION ]	Repair harness or connectors.