Ensemble logique de capteur d'essieu arrière FAW: Une analyse critique de 4 Composants ABS/TCS de base

Bienvenue dans ce guide technique critique sur le Ensemble logique de capteur d'essieu arrière FAW (Assemblée 555). C'est le complet, high-precision “wheel speed sensing” system for the rear *drive axles* of the FAW Jiefang CA4251P66K24T1A3E5 6×4 tracteur semi-remorque diesel. This assembly is the primary “eyes and ears” for the vehicle’s Anti-lock Braking System (abdos) and Traction Control System (TCS).

Le Ensemble logique de capteur d'essieu arrière FAW est un ensemble de composants avec un élément vital “logique” fonction: to precisely measure the rotational speed of each rear drive wheel and report it, in real-time, to the truck’s main ECU and ABS computer. This data is the foundation of all modern active safety systems on the 6×4 tracteur.

Ce guide détaillé est une ressource essentielle pour les techniciens professionnels diesel et les spécialistes des pièces détachées.. Nous déconstruirons l'ensemble Ensemble logique de capteur d'essieu arrière FAW dans son 4 core serviceable components: the ‘Wheel speed sensor’ (3605360-A6T-S), the ‘Sensor bracket’ (3550117A377-S), the ‘Sensor sleeve’ (3550361-6S), and the ‘Wire guide bushing’ (3605221-A6T-S). Un échec dans ce domaine Ensemble logique de capteur d'essieu arrière FAW can compromise the truck’s safety and braking performance.

Le “Logique” of ABS and Traction Control (TCS)

Le Ensemble logique de capteur d'essieu arrière FAW is the sensory input for the truck’s most critical active safety systems. C'est “logique” is not mechanical, but electronic. It answers one question, hundreds of times per second: “How fast is this wheel turning?” This data is essential for both the Anti-lock Braking System (abdos) and the Traction Control System (TCS).

**Anti-lock Braking (abdos) Logique:** When a driver performs a “panic stop” on a wet or icy road, the immense force from the brake chambers can “verrouillage” the drive wheels. A locked wheel has zero traction and can cause a dangerous “jackknife” situation. Le Ensemble logique de capteur d'essieu arrière FAW prevents this. The moment a sensor (3605360-A6T-S) reports a wheel speed of “zero” (a lock-up), the ABS computer instantly commands the brake solenoid (see Assembly 539/545) to release and re-apply the brake on that specific wheel, “pumping” it far faster than any human. Ce “anti-lock” logic keeps the wheel *just* on the verge of locking, providing maximum stopping power while maintaining stability.

**Traction Control (TCS) Logique:** This same Ensemble logique de capteur d'essieu arrière FAW fournit le “logique” for acceleration. If the 6×4 tractor is on a split-traction surface (Par exemple, one wheel on ice, one on pavement) and the driver accelerates, the wheel on the ice will spin uselessly, wasting power. The ECU sees this “spin-up” (one wheel spinning much faster than the others) via the sensor signal. It then can automatically apply a small amount of brake to *just that wheel* (or cut engine power). Ce “logique” fools the axle’s differential into sending torque to the wheel that *does* have traction, allowing the truck to move. This entire safety net is built on the data provided by the Ensemble logique de capteur d'essieu arrière FAW.

Composant principal 1: ‘Wheel Speed Sensor’ (3605360-A6T-S)

The star of the Ensemble logique de capteur d'essieu arrière FAW is the ‘Wheel speed sensor’ (3605360-A6T-S). La liste des pièces en appelle à deux, one for each side of the drive axle. C'est l'électronique “ramasser” that generates the speed signal.

Il s'agit généralement d'un “Hall-effect” ou “magnetic reluctance” capteur. C'est “logique” is to detect magnetic fields. It is mounted via the ‘Sensor bracket’ (3550117A377-S) so that its tip is positioned a fraction of a millimeter away from the ‘ABS ring’ (un “anneau de tonalité” with teeth, which is part of the wheel hub assembly, see Assembly 524/525).

As the wheel hub spins, the teeth of the ABS ring fly past the sensor’s tip. Each “tooth” et “écart” creates a “pulse” in the magnetic field. The sensor reads these pulses and sends them as a digital signal (un “square wave”) to the ECU. The *frequency* of these pulses is directly proportional to the wheel’s speed. The ECU counts these pulses and knows, with pinpoint accuracy, how fast the wheel is turning.

This is the most common failure point in the Ensemble logique de capteur d'essieu arrière FAW. The sensor itself is a sealed electronic unit, but it lives in a hostile environment. It can be damaged by:

• **Debris:** A buildup of brake dust and metallic “fuzz” from the brake drum on the magnetic tip can block the signal.
• **Dommage:** A rock or road debris can strike the sensor or its wiring, breaking the circuit.
• **Air Gap:** If the ‘Sensor bracket’ (3550117A377-S) is bent or corroded, le “air gap” between the sensor and the ring will be too large, resulting in a weak or non-existent signal.

A failure of this sensor will immediately trigger an ABS warning light on the dashboard and disable both the ABS and traction control systems, reverting the truck to standard, non-logic braking. A faulty Ensemble logique de capteur d'essieu arrière FAW is a critical safety issue.

Composant principal 2: Le système de montage (Support & Manche)

The ‘Sensor bracket’ (3550117A377-S) and ‘Sensor sleeve’ (3550361-6S) sont les “Bracket Logic” une partie du Ensemble logique de capteur d'essieu arrière FAW.

**’Sensor bracket’ (3550117A377-S):** This is far more than a simple bracket; it is a **precision alignment device**. C'est “logique” is to hold the ‘Wheel speed sensor’ in the *exact* correct position and at the *exact* correct angle relative to the ABS tone ring. Le “air gap” (the distance between the sensor tip and the ring’s teeth) is the most critical tolerance in the entire Ensemble logique de capteur d'essieu arrière FAW.

* **If the gap is too large,** the magnetic pulse from the passing teeth will be too weak for the sensor to read, resulting in a “no signal” fault. * **If the gap is too small,** the spinning ABS ring (which can have a tiny “wobble” ou “runout”) can strike the sensor tip, destroying it.

**’Sensor sleeve’ (3550361-6S):** Ce composant “logique” is one of protection and precise fit. Ce “manche” is a bushing, typically made of a non-corroding material like bronze, brass, or a high-temperature polymer. The ‘Wheel speed sensor’ is inserted *through* this sleeve, which is itself pressed into the ‘Sensor bracket’. This prevents the sensor body (plastic/aluminum) from corroding and “seizing” to the steel or iron bracket, Assurer le Ensemble logique de capteur d'essieu arrière FAW can be serviced.

Composant principal 3: ‘Wire Guide Bushing’ (3605221-A6T-S)

The final component of the Ensemble logique de capteur d'essieu arrière FAW is the ‘Wheel speed sensor wire guide bushing’ (3605221-A6T-S). This simple-looking part is a critical “logique” component for reliability.

The sensor wire must run from the wheel-end, along the axle housing, and up to the chassis frame harness. This entire path is a “hostile environment” full of heat (from the brakes and differential), vibration, and flying road debris (rochers, glace, etc.).

Ce “guide bushing” is a specialized, high-temperature rubber or polymer grommet. It is used to safely pass the wire through a hole in a chassis bracket. C'est “logique” is to prevent **chafing**. Without this bushing, the sharp, metal edge of the bracket hole would, under constant vibration, rub through the wire’s insulation. This would cause a short-circuit, grounding out the sensor signal and disabling the ABS. This simple bushing is the “armor” that protects the “système nerveux” de la Ensemble logique de capteur d'essieu arrière FAW.

FAW Rear Axle Sensor Logic Assembly Parts List

Le tableau suivant fournit l'intégralité, ventilation détaillée de tous 4 components identified in the ‘Rear Axle Sensor Logic Assembly’ (555) schéma du tracteur FAW CA4251P66K24T1A3E5.

Spécifications techniques et contexte d'assemblage

Les spécifications pour le Ensemble logique de capteur d'essieu arrière FAW are defined by its function as the primary data-gathering tool for the vehicle’s active safety systems. Le Ensemble logique de capteur d'essieu arrière FAW is a high-precision, système critique pour la sécurité.