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HOMESERVICE MANUALSTOYOTA2004MATRIX XR, FWD, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 98 (MULTIPLEX CONTROL SYSTEMS)DIAGNOSTIC TESTSDTC B1241/41: BODY CONTROL ECU SWITCH CIRCUIT DIAGNOSISDIAGNOSTIC PROCEDURE
2004 Toyota Matrix XR, FWD, Standard

Diagnostic Procedure

2004 Toyota Matrix XR, FWD, StandardSECTION Diagnostic Procedure
WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

DTC B1241/41 will set when body control ECU detects one of the following normally open switches closed: luggage compartment door opener, parking brake, taillight, headlight, dimmer, auto light, luggage compartment light, door unlock detection, door courtesy or stop light. DTC B1241/41 will also set when body control ECU detects one of the following normally closed switches open: seat belt buckle or park/neutral position. Turn ignition on and retrieve DTCs after operating each system. If DTC B1241/41 is present, test switch(es) applicable to that system. If switch(es) tests okay, check and repair wiring harness of switch(es). See SWITCH CIRCUIT-TO-WIRING DIAGRAM INDEX  for appropriate wiring diagram for particular switch. After repairs have been made, perform confirmation test. See CONFIRMATION TEST  under SELF-DIAGNOSTIC SYSTEM.

SWITCH CIRCUIT-TO-WIRING DIAGRAM INDEX

Switch (1) Wiring Diagram
Auto Light HEADLIGHTS
Dimmer HEADLIGHTS
Door Courtesy POWER DOOR LOCKS
Door Unlock Detection POWER DOOR LOCKS
Headlight HEADLIGHTS
Luggage Compartment Light INTERIOR LIGHTS
Luggage Compartment Opener TRUNK, TAILGATE & FUEL DOOR
Parking Brake BODY COMPUTER
Park/Neutral Position TRANSMISSION
Seat Belt Buckle WARNING SYSTEMS
Stop Light EXTERIOR LIGHTS
Taillight HEADLIGHTS
(1) Wiring diagrams are located in SYSTEM WIRING DIAGRAMS - AVALON article.
RENDER: 1.0x

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