The 803695591 NanoBCU Controller is a genuine OEM electronic control unit manufactured by XCMG for motor graders and heavy construction equipment. This compact, intelligent body control unit (BCU) manages lighting circuits, wiper systems, horn activation, and auxiliary outputs with integrated diagnostics and CAN bus communication.
Engineered to withstand extreme vibration, temperature swings, and moisture, the 803695591 NanoBCU features a potted IP67 housing and automotive-grade components. It directly replaces failed or corrupted body controllers on XCMG GR series graders and compatible machinery.
Each unit is pre-programmed with XCMG’s proprietary firmware, offering configurable outputs, short-circuit protection, and load-dump survival. The NanoBCU reduces wiring complexity by up to 40% while providing advanced diagnostics via the vehicle’s CAN bus network.
| Parameter | Specification |
|---|---|
| OEM Number | 803695591 |
| Brand | XCMG (Genuine Original Equipment) |
| Product Type | NanoBCU – Body Control Unit (BCU) |
| Operating Voltage | 24V DC (18V – 32V range) |
| Microcontroller | 32-bit ARM Cortex-M4, 168 MHz |
| Flash Memory | 1 MB (with ECC) |
| RAM | 128 KB |
| Communication Protocols | CAN 2.0B (J1939), LIN bus |
| High-Side Outputs | 10 channels, 5A each (peak 10A) |
| Low-Side Outputs | 4 channels, 3A each |
| Digital Inputs | 12 (configurable as wake-up or analog) |
| Analog Inputs | 4 (0-32V, 12-bit resolution) |
| PWM Outputs | 4 channels (100Hz – 2kHz) |
| Protection Features | Overcurrent, short circuit, overvoltage, reverse polarity |
| Operating Temperature | -40°C to +105°C |
| Ingress Protection | IP67 (potted housing, sealed connectors) |
| Connectors | 2 x 24-pin Deutsch (DT series) |
| Diagnostics | Built-in fault logging, CAN-based DTCs |
| Dimensions (L×W×H) | 140 mm × 90 mm × 35 mm |
| Weight | 350 g (0.77 lbs) |
| Compatible Models | XCMG GR135, GR165, GR180, GR215, GR260, GR300, GR350 motor graders |
| Superseded Part Numbers | 803695401, 803695512, 803695688 |
| Certifications | CE, RoHS, ISO 9001:2015, IATF 16949 |
The XCMG 803695591 NanoBCU Controller replaces multiple discrete relays and timers with a single, programmable electronic unit. It monitors inputs from switches and sensors, then activates outputs for headlights, work lights, windshield wipers, washer pumps, horn, beacons, and cabin convenience features. This reduces wiring harness complexity, weight, and failure points.
The controller communicates with the engine ECU, transmission TCU, and dashboard display via the CAN bus (J1939 protocol). This enables features such as automatic light activation based on ambient light (if a sensor is present), wiper speed synchronization with vehicle speed, and remote diagnostics. Fault codes are stored in non-volatile memory and can be read using XCMG’s service tool.
The NanoBCU’s compact size allows it to be mounted inside the cab fuse panel or behind the dashboard. The potted construction (encapsulated in epoxy) makes it impervious to moisture, dust, and vibration – common failure causes for open-circuit PCBs. The 803695591 is rated for 1 million hours MTBF.
The 803695591 NanoBCU is a direct replacement for the original body controller on XCMG GR series graders. Installation requires disconnecting the battery, removing the old unit (two Deutsch connectors and two mounting screws), and installing the new controller. No additional programming is needed because the firmware is pre-loaded with the correct configuration for your machine model.
However, for graders with optional equipment (e.g., extra work lights, beacon, or aftermarket accessories), the controller can be re-flashed by an authorized XCMG dealer using the NanoBCU configuration software. The controller features a bootloader for firmware updates via CAN bus without removing the unit.
Common failure symptoms: lights stay on or off, wipers operate erratically, horn does not work, or multiple electrical functions fail simultaneously. A faulty BCU may also cause CAN bus communication errors (check engine light with codes U0100-U0299). Replacing with the 803695591 restores all body electrical functions.
XCMG designs the 803695591 NanoBCU to survive the harshest conditions: -40°C arctic starts, +105°C engine compartment heat, 20g vibration, and pressure washing. The housing is made of die-cast aluminum with a black powder coating, which also acts as a heat sink for the power MOSFETs. The connectors are sealed Deutsch DT series, rated IP67 when mated.
Each controller undergoes 100% functional testing at the factory: all outputs are driven at rated current for 30 minutes while the unit is thermally cycled. High-potential testing (1500V AC) ensures insulation integrity. The unit also passes 500 hours of salt spray (ASTM B117) and 100 thermal shock cycles from -40°C to +105°C.
The NanoBCU’s output drivers include overcurrent and overtemperature shutdown with automatic retry. If a short circuit is detected, the affected output is turned off and a diagnostic trouble code is logged. This prevents wiring fires and protects the controller from damage.
Aftermarket body controllers are often generic units with incorrect pinouts or missing features. The genuine XCMG NanoBCU is specifically calibrated for the electrical loads and timing requirements of GR series graders. Using a counterfeit controller can cause light flickering, delayed wiper operation, or even damage to other ECUs due to improper CAN bus termination.
Additionally, genuine XCMG controllers include a unique serial number and are traceable. XCMG provides a 12-month unlimited-hour warranty against defects. The 803695591 supersedes older part numbers 803695401 and 803695512, with improved processor speed and additional diagnostic features.
For fleet managers, using genuine NanoBCU units ensures consistent behavior across all machines and simplifies troubleshooting with XCMG’s diagnostic software.
The 803695591 NanoBCU supports both passive and active diagnostics. Using a CAN bus scanner (e.g., XCMG’s DiagMaster tool), technicians can read real-time input states, output currents, and stored fault codes. The controller can also output a dedicated “service lamp” signal to warn operators of body system faults.
Configuration parameters such as work light flashing patterns, wiper intermittent delays, and horn pulse duration can be adjusted via the CAN bus without replacing the unit. This allows customization for specific applications (e.g., road maintenance vs. mining).
For advanced users, the NanoBCU includes a built-in “limp-home” mode: if the CAN bus fails, the controller will still respond to basic switch inputs (e.g., hazard lights, horn) to ensure safety.
The 803695591 NanoBCU Controller is stocked in XCMG regional warehouses in North America (Houston), Europe (Rotterdam), Middle East (Dubai), and Asia (Shanghai). Standard air freight delivers within 3-7 business days worldwide. Expedited shipping (1-2 days) is available for urgent breakdowns.
Bulk orders (5+ units) receive volume discounts and can be shipped via sea freight. Each controller is individually packaged in an anti-static bag with a desiccant and foam padding. For large fleets, consignment stock programs are available.
Don’t let a failed body control unit paralyze your grader’s electrical systems. Order the genuine XCMG 803695591 NanoBCU Controller today and restore intelligent, reliable control of lighting, wipers, and auxiliary functions.
The 803695591 NanoBCU represents XCMG’s commitment to advanced electronics for heavy equipment. By replacing discrete relays with solid-state intelligence, it improves reliability, simplifies troubleshooting, and reduces downtime. Keep a spare NanoBCU in your parts inventory for rapid field replacement.
Upgrade your motor grader’s body control system with the XCMG NanoBCU. Genuine, robust, and field-proven – designed by the engineers who know your machine best.
