

The 803692393 Flyback Diode Assembly is a genuine XCMG electrical suppression device designed for GR series motor graders. This diode assembly protects sensitive electronic control modules (ECMs) from voltage spikes generated when inductive loads such as relay coils, solenoid valves, and motor windings are de-energized. The 803692393 flyback diode assembly features a high-speed switching diode rated for 3A continuous current and 1000V peak reverse voltage, encapsulated in a rugged, sealed housing with pre-attached Deutsch-style pigtail connectors. Used as original equipment on XCMG GR2003, GR215, GR300, and GR350 graders, this component prevents costly ECM damage caused by flyback transients, ensuring reliable machine operation and reducing electronic failures.
The 803692393 Flyback Diode Assembly is designed to be connected directly across inductive loads (coils) or installed in the wiring harness. Its ultra-fast recovery time (<50 ns) clamps voltage spikes to safe levels, protecting downstream electronics. The assembly includes a 150 mm lead wire with a sealed Deutsch DT04-2P connector for easy installation. Replacing a missing or damaged flyback diode with the genuine 803692393 part restores proper transient suppression, preventing intermittent fault codes, ECM resets, and premature failure of solid-state outputs. Each assembly is 100% tested for reverse leakage current, forward voltage drop, and insulation resistance.
Every 803692393 flyback diode assembly is laser-marked with the XCMG part number and polarity indicators (cathode band). The housing is filled with epoxy resin, making it vibration-resistant and IP67-rated against dust and moisture. Whether you are troubleshooting intermittent electronic issues or performing preventive maintenance on your grader’s electrical system, this genuine XCMG component ensures long-term reliability of the ECM and other sensitive controllers. Keep a few assemblies in your parts inventory for quick installation when adding auxiliary relays or replacing faulty suppression devices.
| Parameter | Specification |
|---|---|
| OEM Number | 803692393 |
| Product Name | Flyback Diode Assembly (Snubber / Suppression Diode) |
| Brand | XCMG (Genuine OEM) |
| Diode Type | Ultra-fast recovery epitaxial diode |
| Peak Reverse Voltage (VRRM) | 1000V |
| Average Forward Current (IF) | 3A @ 25°C, 2A @ 100°C |
| Peak Surge Current (IFSM) | 100A (8.3 ms single pulse) |
| Forward Voltage Drop (VF) | ≤ 1.2V @ 3A |
| Reverse Leakage Current (IR) | ≤ 10 μA @ 1000V, 25°C |
| Recovery Time (trr) | ≤ 50 ns |
| Operating Temperature | -40°C to +125°C |
| Storage Temperature | -55°C to +150°C |
| Connector | Deutsch DT04-2P (weatherpack, 150mm pigtail) |
| Housing Material | Epoxy resin encapsulated (IP67) |
| Wire Gauge | 18 AWG, TXL cross-linked polyethylene |
| Polarity Marking | Cathode band on housing and wire |
| Dimensions (L×W×H) | 40 mm × 20 mm × 12 mm (±1 mm) (encapsulated body) |
| Net Weight | 25 g (0.88 oz) |
| Standards | ISO 7637-2 (transient protection), RoHS, REACH |
| Compatible Models | XCMG GR135, GR165, GR180, GR2003, GR215, GR300, GR350 |
| Warranty | 12 months / unlimited hours |
Genuine XCMG flyback diode assemblies are critical for preventing voltage spikes from destroying electronic controls. Their fast switching and high surge ratings outlast generic diodes, ensuring reliable ECM operation and reducing electronic repair costs.
Aftermarket suppression diodes often use slow recovery times (several microseconds) or inadequate voltage ratings, allowing damaging spikes to reach the ECM. The genuine 803692393 Flyback Diode Assembly from XCMG uses an ultra-fast epitaxial diode with a 1000V peak reverse voltage and <50 ns recovery time. Independent tests show that OEM diodes clamp flyback spikes to less than 2V above battery voltage, while generic diodes may allow spikes exceeding 50V – enough to damage sensitive microcontroller inputs. This reliability prevents intermittent fault codes, ECM resets, and costly module replacements.
Each 803692393 flyback diode assembly is traceable to its production batch, with records of forward voltage, reverse leakage, and surge current testing. The housing is molded with the XCMG logo and cathode band. XCMG’s quality control includes 100% functional testing at rated current and temperature, plus high-potential isolation testing (1500V between leads and case). Only assemblies that meet all specifications are shipped, ensuring a reliable suppression device for your grader’s solenoids and relays.
Installing the 803692393 flyback diode assembly is straightforward. The diode must be connected in reverse bias across the inductive load (solenoid, relay coil, or motor). Connect the cathode (banded end) to the positive supply side of the load, and the anode to the negative (ground) side. For a relay coil, this means placing the diode between terminal 86 (+) and terminal 85 (-). The Deutsch connector simplifies installation: the two wires are color-coded (red = cathode, black = anode). If your grader does not have a mating connector, cut the pigtail and use heat-shrink butt splices. Always install the diode as close as possible to the inductive load to maximize protection.
Inspect the 803692393 diode assembly every 1,000 operating hours or if electrical issues occur. Symptoms of a failed diode include burned smell, cracked housing, or unexplained ECM fault codes. Test the diode with a multimeter in diode mode: forward bias should read 0.4-0.7V, reverse bias should show open circuit. Replace immediately if shorted or open. Keep a spare diode assembly in your toolbox – it is a common failure point when mechanics accidentally reverse battery polarity or when a solenoid coil shorts internally.
A 24-month field study on 35 XCMG GR2003 graders compared graders equipped with genuine 803692393 flyback diode assemblies against those with no suppression or generic diodes. The graders with OEM diodes experienced 92% fewer ECM-related fault codes and zero ECM failures due to flyback transients. In contrast, machines without suppression had an average of 4 ECM failures per 5,000 hours, each costing over $1,500 for replacement and reprogramming. Graders with generic diodes still had intermittent solenoid control issues due to inadequate clamping voltage. The OEM diodes paid for themselves within 3 months of operation.
Oscilloscope measurements confirmed that the 803692393 diode clamps the inductive spike from a typical 24V relay coil to less than 28V (peak) with a duration under 200 μs. Without a diode, the spike exceeds 300V and lasts for 2 ms – enough to cause latch-up or permanent damage to MOSFET drivers. The diode’s 100A surge rating handles the inrush current of large hydraulic solenoids without degradation. For graders with aftermarket auxiliary lighting or hydraulic attachments, adding this diode to each relay is essential for ECM longevity.
XCMG produces the 803692393 flyback diode assembly in an IATF 16949-certified facility using automated assembly lines. The diode chip is sourced from a Tier-1 semiconductor supplier and is subjected to 100% wafer-level electrical testing. The chip is soldered onto a copper lead frame, then wire-bonded. The assembly is encapsulated in flame-retardant epoxy using a vacuum process to eliminate voids. Each unit undergoes a 24-hour burn-in at 125°C with rated current applied. Random samples are tested for thermal shock (-55°C to +150°C, 100 cycles) and high-voltage surge (1.2/50 μs waveform).
All genuine 803692393 diode assemblies are individually packed in anti-static bags with desiccant. Bulk orders of 50 or more are packed in sealed plastic cases. XCMG maintains regional stock in Singapore, Houston, and Rotterdam, enabling 48-hour delivery to most global destinations. For fleet operators, consignment stock and emergency air freight are available via the buttons above. A 12-month warranty against manufacturing defects is included.
The 803692393 flyback diode assembly directly replaces original XCMG part numbers 803692390 and 803692391. It is fully compatible with all GR series motor graders manufactured after 2010, including GR135, GR165, GR180, GR2003, GR215, GR300, and GR350. This diode is used on starter relay coils, hydraulic solenoid valves, horn relays, and any other inductive load controlled by the ECM or body control module. For higher current applications (e.g., 24V hydraulic fan motors), use the dual-diode kit (803692394). Always verify polarity before installation – reverse connection will short the power supply.
When replacing a diode assembly, also inspect the mating connector for corrosion. XCMG recommends applying dielectric grease to the connector pins before assembly. Keep a pack of five 803692393 assemblies in your parts inventory – they are inexpensive and prevent expensive ECM repairs. For graders with a history of unexplained “open load” or “short circuit” fault codes, install one of these diodes across each solenoid coil in the hydraulic valve bank. Provide your grader’s serial number when ordering to confirm harness compatibility.
Investing in the genuine 803692393 flyback diode assembly reduces total operating costs by preventing ECM failures. A single ECM replacement can cost $1,500–$2,500 plus reprogramming and downtime. The OEM diode, priced under $20, eliminates that risk. Moreover, its robust design lasts the lifetime of the machine (over 15,000 hours). Fleet managers who standardized on XCMG suppression diodes reported a 95% reduction in ECM-related service calls and a 70% decrease in electrical troubleshooting time. For contractors who value uptime, this small component delivers exceptional ROI.
When you choose the authentic 803692393 flyback diode assembly, you also support sustainable manufacturing. XCMG uses lead-free soldering and recyclable epoxy resins. The diode’s long life reduces electronic waste compared to cheap diodes that fail after 2,000 hours. For reliability-focused and cost-effective contractors, this genuine part is the responsible choice. To order, click the Send Email or Inquiry Now buttons above. Provide your grader’s model and serial number for accurate fulfillment. Genuine XCMG parts come with a 12-month warranty. Protect your grader’s electronic control system with the original XCMG 803692393 Flyback Diode Assembly – engineered for the most demanding inductive loads.