Description

Acura TSX 2004 Service Manual

If you’re chasing an electrical problem on a 2004 Acura TSX—especially in the brake light circuit—you need the factory documentation. Not a reprint from some third-party outfit that guessed the wire colors. This Acura TSX 2004 Service Manual is OEM. Printed from the same files the dealer techs used. 48 pages, all dedicated to the exterior lighting system: component locations, connector views, and full wiring diagrams.

Component Location Index: Every Light Component Mapped

Page 1 starts the component location index. You get diagrams showing the multi-relay box, daytime running lights relay (Canada), under-hood fuse/relay box, headlights, side turn signal lights, front turn signal lights, front parking lights, and the HID unit. The manual also locates the lights-on indicator, high beam indicator, DRL indicator, combination switch control unit, combination light switch, and the brake pedal position switch. Wire colors are listed: RED/BLK, RED/BLU, BLK, BLU/WHT for the DRL relay. If you’ve ever spent an hour hunting for a relay only to find it behind the bumper, this index saves you that time.

Brake Lights Wiring Diagram: Factory-Correct Circuits

Page 4 shows the brake light circuit. The manual documents the brake pedal position switch (closed when pedal pressed), the VSA modulator-control unit, MICU, ECM/PCM, and the three brake lights (left, right, high mount). The wire colors are WHT/BLK for the brake feed and BLK for grounds. If you’re diagnosing a brake light that stays on or doesn’t work, start here. The diagram shows the under-hood fuse/relay box with No.13 (20A) fuse feeding the switch. Without this sheet, you’re guessing.

Does This Manual Cover the Full Vehicle?

It covers the exterior lighting system only. That includes headlights, front/rear turn signals, parking lights, taillights, brake lights, backup lights, license plate lights, and side markers. Also the HID unit and DRL system for Canadian models. If you need engine or transmission specs, look for the full service manual. This 48-page document is a specialized extract from the larger set—but for lighting diagnostics, it’s the only piece you need.

3 Wiring Diagrams You Get in This Service Manual

Page 5 shows the exterior lights wiring diagram for USA models, including the under-hood fuse/relay box, relay control module, and individual circuits for left and right headlights, HID units, parking lights, taillights, and license plate lights. The manual includes at least three diagram sheets covering brake lights, exterior lights (USA), and exterior lights (Canada). Each diagram has proper wire color codes, connector pin numbers, and ground locations. For example, the brake light diagram on page 4 shows the VSA modulator-control unit, MICU, and ECM/PCM connections. You get the same level of detail for every exterior lighting circuit.

OEM Documentation: Why Aftermarket Copies Fail

I’ve seen aftermarket manuals that combine diagrams from different years or crop out connector views. This OEM Acura service manual has the same layout as what the dealer used in 2004. The wire color abbreviations match the actual harness—no guessing whether RED/BLK means red with black stripe or the other way around. For a broader understanding of electrical standards, see the Automotive Industry Overview. If you want context on OEM documentation practices, refer to Automotive Industry Overview. Use the factory sheets or get ready to chase phantom shorts.

Related Manuals

• Acura TSX 2004 Service Manual
• Acura Integra 1998 Service Manual – OEM Factory Specs
• 1993 Acura Vigor Service Manual – OEM Factory Specs

How many pages does this manual have?

48 pages.

Does this manual include torque specifications for brake components?

This manual focuses on electrical troubleshooting and component locations for the exterior lighting system. It does not cover mechanical brake service procedures such as pad replacement or caliper torque specs. For that, you would need the complete Acura TSX factory service manual. The 48-page document here is a dedicated extract for the lighting circuits, including the brake lights circuit on page 4. The component location index on pages 1-3 shows the brake pedal position switch location, which is critical for diagnosing brake light issues.

If you’re working on a 2004 Acura TSX and need the real wiring data, don’t waste time with generic diagrams. Access the Factory Manual now. It’s the same document the dealer techs kept in their drawer.