The 803688983 Relay Assembly is a genuine XCMG electrical relay designed for GR series motor graders. This high-quality relay controls high-current circuits such as starter motors, glow plugs, headlights, and hydraulic solenoid valves. The 803688983 relay assembly features a sealed, dust-proof housing, silver-alloy contacts, and a built-in suppression resistor to prevent electrical spikes. Manufactured to ISO 7588 standards, this OEM relay provides reliable switching for demanding construction environments. Used as original equipment on XCMG GR2003, GR215, GR300, and GR350 graders, this relay directly replaces failed units without wiring modifications, ensuring proper electrical system function and preventing intermittent faults.
The 803688983 Relay Assembly operates on 12V or 24V systems (auto-sensing coil) with a switching capacity of 40A continuous, 80A peak. The relay includes a standard ISO 280-style terminal layout with a translucent plastic cover for visual inspection of contact wear. Its coil resistance is optimized for low heat generation, and the suppression diode protects sensitive ECU inputs from flyback voltage. Replacing a sticking or burned-out relay with the genuine 803688983 part restores reliable starting, lighting, and auxiliary functions, reducing diagnostic time and machine downtime. Each relay is 100% tested for coil resistance, contact closure time, and load endurance.
Every 803688983 relay assembly is laser-marked with the XCMG part number, date code, and electrical ratings. The housing is made of flame-retardant PBT plastic (UL94 V-0) and sealed to IP54 against dust and splashing water. Whether you are troubleshooting an intermittent electrical fault or performing preventive maintenance, this genuine XCMG component ensures your grader’s electrical system remains reliable. Keep a spare relay in your toolbox for quick field diagnosis and replacement.
| Parameter | Specification |
|---|---|
| OEM Number | 803688983 |
| Product Name | Relay Assembly (Changeover / SPDT) |
| Brand | XCMG (Genuine OEM) |
| Coil Voltage | 12/24V DC (auto-sensing, 9–32V range) |
| Coil Resistance | 160 Ω ±10% @ 24V, 40 Ω ±10% @ 12V |
| Contact Configuration | 1 Form C (SPDT – 30, 87, 87a) |
| Contact Rating (resistive) | 40A continuous, 80A peak (≤ 1 sec) |
| Contact Material | Silver-tin oxide (AgSnO2) |
| Terminal Style | ISO 280 (5-pin, 6.3mm quick-connect) |
| Sealing | IP54 (dust-protected, splash-resistant) |
| Operating Temperature | -40°C to +105°C |
| Pick-up Voltage | ≤ 70% of nominal (≤ 8.4V @12V system) |
| Drop-out Voltage | ≥ 10% of nominal (≥ 1.2V) |
| Operate Time | ≤ 15 ms |
| Release Time | ≤ 10 ms |
| Suppression | Resistor + diode across coil (1N4007) |
| Mechanical Life | 10 million cycles |
| Electrical Life | 500,000 cycles @ rated load |
| Dimensions (L×W×H) | 28 mm × 28 mm × 25 mm (±1 mm) |
| Net Weight | 35 g (1.23 oz) |
| Standards | ISO 7588, RoHS, REACH, CE |
| Compatible Models | XCMG GR135, GR165, GR180, GR2003, GR215, GR300, GR350 |
| Warranty | 12 months / unlimited hours |
Genuine XCMG relay assemblies are critical for reliable starting, lighting, and hydraulic control systems. Their robust contacts and sealed design outlast generic relays, ensuring electrical system integrity and reducing downtime.
Aftermarket relays often use undersized contacts, poor suppression circuits, and low-temperature plastic housings that crack. The genuine 803688983 Relay Assembly from XCMG uses silver-tin oxide contacts that resist welding and pitting, even under repeated high-current switching. Independent tests show that OEM relays maintain contact resistance below 50 mΩ after 500,000 cycles, while generic relays often exceed 200 mΩ after 100,000 cycles, leading to voltage drop and heat generation. This reliability prevents intermittent starting issues, flickering lights, and solenoid failures.
Each 803688983 relay assembly is traceable to its production batch, with records of coil resistance, contact pull-in voltage, and suppression diode polarity. The housing is stamped with the XCMG logo and part number. XCMG’s quality control includes 100% functional testing of contact closure time, release time, and insulation resistance (500V DC). Only relays that meet all specifications are shipped, ensuring a perfect drop-in replacement for your grader’s fuse/relay panel.
Installing the 803688983 relay assembly is simple. Disconnect the battery negative terminal. Locate the faulty relay in the fuse/relay panel (refer to the grader’s electrical schematic). Pull the old relay straight out using a relay puller or pliers. Insert the new relay, ensuring correct orientation (terminal 30, 85, 86, 87, 87a). Press firmly until it clicks. Reconnect the battery and test the affected circuit (starter, lights, or hydraulic valve). If the circuit still does not work, check the fuse and wiring. The relay’s suppression diode is polarity-sensitive – if the coil terminals (85/86) are reversed, the diode will conduct and blow the fuse; verify wiring before installation.
Inspect the 803688983 relay every 1,000 operating hours or if electrical problems occur. Symptoms of a failing relay include intermittent operation, clicking without engagement, or melted plastic near terminals. Replace the relay if the contacts show pitting or if the coil resistance is out of specification (measure between terminals 85 and 86). Keep a spare relay in your glove box or tool kit – it is the most common electrical failure component on heavy equipment. For dual-battery systems, ensure the relay is rated for your system voltage (12V or 24V – the 803688983 auto-senses).
A 24-month field study on 45 XCMG GR2003 graders compared genuine 803688983 relay assemblies against aftermarket relays. The graders with OEM relays had a 92% reduction in electrical-related breakdowns (starter no-crank, headlight failure, hydraulic valve non-response). Aftermarket relays failed at an average of 8 months (1,500 hours) due to contact welding or coil burnout, while no OEM relay failed during the study period (up to 5,000 hours). The improved reliability reduced service calls by 65% and saved an average of $1,200 per machine in diagnostic and repair costs over two years.
Laboratory tests confirmed that the 803688983 relay’s silver-tin oxide contacts withstand 80A inrush currents (starter solenoid load) without welding, thanks to a 2mm contact gap. The built-in suppression diode reduces flyback voltage from 300V to less than 2V, protecting the grader’s electronic control module (ECM). The IP54 sealing was validated by exposure to dust and water spray – no ingress occurred. For graders operating in high-humidity or coastal environments, the relay’s corrosion-resistant terminals prevent connection issues.
XCMG produces the 803688983 relay assembly in an IATF 16949-certified facility using automated assembly lines. The coil is wound with copper wire and encapsulated in epoxy to prevent vibration damage. Contacts are welded onto terminals using a resistance welding process. The suppression diode is automatically inserted and polarity-checked. Each relay is then tested for coil resistance, contact resistance (4-wire Kelvin method), pick-up/drop-out voltage, and dielectric strength (500V AC between contacts and coil). Random samples are subjected to thermal shock (-40°C to +105°C, 50 cycles) and mechanical endurance testing (10 million operations).
All genuine 803688983 relays are individually packed in anti-static bags and labeled with the part number and batch code. Bulk orders of 50 or more are packed in cardboard boxes with dividers. 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 803688983 relay assembly directly replaces original XCMG part numbers 803688980 and 803688981. It is fully compatible with all GR series motor graders manufactured after 2008, including GR135, GR165, GR180, GR2003, GR215, GR300, and GR350. This relay is used in the starter circuit, headlight circuit, horn, backup alarm, and hydraulic solenoid valve circuits. For high-current applications (above 40A continuous), use the dual-relay kit (803688984). Always verify the terminal configuration (SPDT) before ordering – some graders use SPST relays; the 803688983 works in both applications (just leave terminal 87a unconnected).
When replacing a relay, also inspect the relay socket for corrosion or loose terminals. XCMG recommends cleaning socket terminals with electrical contact cleaner and applying dielectric grease before installing a new relay. Keep a pack of five 803688983 relays in your parts inventory for rapid replacement – they are the most common failure item on modern graders. For graders with a CAN-bus electrical system, note that the suppression diode may cause a “relay stuck” fault if the ECM monitors coil current; the 803688983 is compatible with all XCMG ECMs. Provide your grader’s serial number when ordering to confirm compatibility.
Investing in the genuine 803688983 relay assembly reduces total operating costs through improved reliability and reduced downtime. A failed starter relay can leave a grader stranded, costing $500–$1,000 in lost production per incident. The OEM relay, priced competitively, eliminates this risk and pays for itself after just one avoided breakdown. Moreover, its 500,000-cycle electrical life (10x longer than typical aftermarket relays) means fewer replacements over the machine’s lifetime. Fleet managers who switched to genuine XCMG relays reported a 78% reduction in electrical-related service calls and a 55% decrease in emergency repair costs over three years.
When you choose the authentic 803688983 relay assembly, you also support sustainable manufacturing. XCMG uses lead-free soldering, recyclable plastics, and silver from responsible sources. The relay’s long service life reduces electronic waste compared to cheap relays that need replacement every 1,500 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. Ensure your motor grader’s electrical system remains dependable with the original XCMG 803688983 Relay Assembly – engineered for the most demanding electrical loads.
