Description

Infiniti G35 2003 Service Manual – Brake Control System (70 Pages)

If you are wrenching on a 2003 Infiniti G35 and the ABS light is on or the VDC is acting up, the last thing you need is a generic wiring diagram that leaves you chasing ghosts. I have seen too many guys replace a perfectly good actuator because some aftermarket schematic showed the wrong pinout. That costs hours and parts you cannot return. The Infiniti G35 2003 Service Manual you are looking at is the factory-issued brake control system document — 70 pages of nothing but VDC/TCS/ABS diagnostics, component specs, and removal procedures. This is what the Infiniti dealer techs used when your car was new. No shortcuts, no guesswork. You get the actual system diagram on page 1 and the SRS precautions that can keep you alive.

Brake Control System Coverage

This manual dives into the hydraulic circuit diagram, the fail-safe functions for each subsystem (VDC, TCS, ABS, EBD), and the CAN communication architecture that links the control unit to the rest of the car. You get the full list of special service tools and commercial tools needed for the job. The on-vehicle service section covers steering angle sensor neutral position adjustment — a step most aftermarket books skip entirely. Need the hydraulic circuit layout? It is mapped out in the General Information chapter. The manual also includes the VDC actuator test procedure, solenoid valve relay checks, and the complete removal and installation sequence for wheel sensors, sensor rotors, the G sensor, and the steering angle sensor.

15 Inspection Procedures for ABS and VDC

The trouble diagnosis section is where this manual earns its keep. It walks you through 15 inspection procedures, starting with Basic Inspection 1 (brake fluid amount, leaks, and brake pads) on page 40, then moving through wheel sensor system, engine system, control unit power and ground, pressure sensor, steering angle sensor, yaw rate / side G sensor, solenoid and VDC change-over valve, ABS motor and motor relay, solenoid valve relay, stop lamp switch, brake fluid level sensor, CAN communication, and the shift position error check for A/T models. Each inspection follows a factory flowchart — you do not guess which circuit to test first. You follow the sequence that catches intermittent faults before they become comebacks.

Check the SRS Precautions Before You Start

Do not open the hood until you have read the SRS precautions on page 1. The manual explicitly warns about deploying the air bag or seat belt pre-tensioner during brake system work. It also covers battery service precautions (disconnect the negative cable and wait at least 3 minutes) and brake system precautions (do not reuse brake fluid, keep the reservoir cap clean). I have seen a technician set off an airbag because he skipped the warning about working near the steering angle sensor. That is a $1,200 mistake and a lost Saturday. This manual prints those warnings in bold for a reason.

What Does This 70-Page Manual Cover?

False expectations cost time. This is not the full vehicle service manual. It is the brake control system supplement — section BRC of the 2003 Infiniti G35 service documentation. It covers VDC/TCS/ABS from theory to component-level repair. You get wiring diagram — VDC, control unit input/output signal standards, CONSULT-II self-diagnosis, data monitor, active test parameters, and the complete inspection component library (VDC OFF switch, VDC relay box, VDC actuator). Also included are symptom tables for excessive ABS operation frequency, unexpected pedal reaction, long braking distance, ABS not operating, pedal vibration, and vehicle jerking during control. For wiring harness repairs, the CAN communication section gives you proper repair precautions.

VDC/TCS/ABS: Factory Diagnostics Flowchart

The manual starts the diagnostic process with an actual diagnosis flowchart — not just a list of possible causes. It tells you how to proceed with diagnosis, ask the customer for complaints, fill out the diagnosis sheet, and locate components using the component installation location diagram. Then you move into CONSULT-II functions: self-diagnosis, data monitor, active test. The standards are given by CONSULT-II, so you know what the control unit should read when everything is healthy. For those of us who work on these cars regularly, the active test lets you command the ABS motor and solenoids to verify hydraulic operation without a road test. That is how you find a sticking valve without risking a crash.

Source Validity: OEM Factory Documentation

Aftermarket manuals often rearrange the diagnostic steps and omit the fail-safe function descriptions. This is a direct digital copy of the Infiniti factory service manual from 2003, published for the G35 coupe (revision April 2004). The content matches what the dealer tech had on his tablet. You get the exact part numbers, torque specs, and connector views that Infiniti released. If you are doing a brake control system repair that involves the VDC actuator or steering angle sensor, you need the OEM data — not a reprint that might be from a different model year or a different market. This is the real thing.

Who Needs This Manual?

DIY owners who want to fix their own ABS or VDC issue without pulling the wrong fuse. Professional mechanics who bill by the hour and cannot afford to chase a bad ground through three different schematics. Shop owners who need to hand a tech a reliable reference for a 2003 G35 that is on the lift right now. Beginners who are willing to follow the factory steps, not skip to the conclusion. If you know how to read a wiring diagram and use a multimeter, this manual gets you to the broken component directly. If you are not comfortable with CAN diagnostics, the manual explains the communication types and how to check for harness damage.

Frequently Asked Questions

Does this manual cover the 2003 Infiniti G35 engine or transmission systems?

No. This is the brake control system section only (70 pages). It focuses on VDC/TCS/ABS, wiring, diagnostics, and component removal. For engine or transmission, you need the corresponding service manuals.

What diagnostic tools do I need to follow the procedures in this manual?

You need a CONSULT-II or compatible scan tool that can read Infiniti ABS/VDC data, a digital multimeter, and basic hand tools for component removal. The manual references commercial service tools like a brake pedal depressor and a steering angle sensor adjustment tool. It also assumes you have access to a wiring diagram (included) and a brake fluid pressure gauge for the actuator tests. For the self-diagnosis steps, the CONSULT-II main function provides self-diagnosis, data monitor, and active test. If you do not have a CONSULT-II, you can still perform the basic inspections (page 40) and wheel sensor tests with a multimeter, but the active test procedures require the factory tool to command solenoid and motor operation. Do not try to bypass the active test with jumper wires — you will risk damaging the control unit.

Access the Factory Manual and get the exact wiring, torque, and diagnostic data that Infiniti wrote for the 2003 G35. This is not a third-party scan of a scan — it is the original factory PDF, 70 pages, ready to use on a tablet or print out for the workbench. Related manuals: Infiniti G35 Coupe 2006 Service Manual, Infiniti G35 2003 Automatic Transmission Service Manual, G35 Body, Lock & Security System Manual 2003-2004. For more context on the broader automotive industry, see Automotive Industry Overview and Manual Transmission.