MERCRUISER 390-7804A3-15248T02 Ignition Control Module 390-7804A3/15248T02 Module/amplifier Freshwater

( Brand: Mercruiser ), ( Manufacturer Part Number: 390-7804A3/15248T02 ), ( Part Type: Ignition Control Module Amplifier )

Review MERCRUISER 390-7804a3/15248t02 Ignition Control Module/amplifier Freshwater

The **Mercruiser 390-7804A3/15248T02 Ignition Control Module/Amplifier (390-7804A3 Freshwater)** is a critical electronic component designed to regulate and amplify the ignition signals within Mercruiser marine engines, ensuring precise and reliable spark generation for optimal combustion efficiency. This high-performance module is engineered to interface seamlessly with the engine s ignition system, converting low-level control signals from the engine control unit (ECU) into stronger, timed pulses that activate the ignition coils. Built to withstand the demanding conditions of marine environments, this module is specifically rated for freshwater applications, distinguishing it from its saltwater counterpart by its corrosion-resistant construction and specialized internal circuitry. Its robust design incorporates advanced semiconductor technology to handle the high voltage demands of modern marine engines while maintaining durability against moisture, vibration, and temperature fluctuations commonly encountered on boats. Whether installed in a cruising yacht, fishing vessel, or performance boat, this ignition control module plays a pivotal role in enhancing engine performance, fuel efficiency, and overall reliability. Replacing a faulty module can restore proper ignition timing, prevent misfires, and prevent potential damage to the engine s ignition components, making it an essential part of routine maintenance and engine diagnostics for Mercruiser owners.

**Pros and Cons of buying a Mercruiser 390-7804A3/15248T02 Ignition Control Module/Amplifier (Freshwater)**

### **Pros**

1. **Compatibility and Reliability** This part is designed specifically for Mercruiser engines, ensuring a proper fit and optimized performance. It is a direct replacement for the original ignition control module, reducing the risk of compatibility issues with aftermarket parts.

2. **Prevents Electrical Failures** The ignition control module regulates the timing and output of the ignition system. A faulty module can cause misfires, stalling, or failure to start. Replacing it resolves these issues, improving engine reliability and preventing further damage.

3. **Easy Installation** As a direct-fit replacement, this module is designed to be straightforward to install, often requiring only basic tools. Many users report that installation takes less than an hour, especially if they have experience with marine electrical work.

4. **Cost-Effective Fix** Replacing the ignition control module is typically far cheaper than overhauling the entire ignition system or replacing the engine. It extends the life of the engine without requiring major repairs.

5. **Warranty Coverage** Purchasing from a reputable dealer or authorized seller often includes a warranty, providing peace of mind in case the part fails prematurely.

6. **Improved Engine Performance** A functioning ignition module ensures proper spark timing, leading to smoother operation, better fuel efficiency, and reduced wear on engine components.

7. **Prevents Water Damage (Freshwater Model)** The freshwater-rated version is designed to handle exposure to freshwater environments, reducing the risk of corrosion or short circuits in marine applications.

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### **Cons**

1. **Potential Counterfeit Parts** Buying from untrusted sellers (e.g., third-party online marketplaces) may result in counterfeit or low-quality replicas. These can fail quickly or not function as intended, leading to wasted money and additional repairs.

2. **Electrical Knowledge Required** While installation is generally simple, troubleshooting electrical issues (e.g., wiring connections, ground problems) may require some technical knowledge. A novice might struggle if the engine has additional electrical faults.

3. **Limited Availability** Depending on the seller, stock may be inconsistent, leading to delays in receiving the part. Some specialized marine supply stores may not carry it in stock.

4. **Cost Compared to DIY Alternatives** If the issue is minor (e.g., a loose connection or corroded terminal), a technician might recommend a simpler fix instead of replacing the entire module. In such cases, the cost-benefit may not justify a full replacement.

5. **Testing Required After Installation** After replacing the module, the engine may need to be tested for proper operation, including checking for misfires, rough idling, or starting issues. If the problem persists, further diagnosis may be needed.

6. **Environmental Factors** Even with a freshwater-rated module, prolonged exposure to saltwater, humidity, or extreme temperatures can still affect performance over time. Regular maintenance is necessary to ensure longevity.

7. **Potential for Overkill** If the ignition issue is caused by something else (e.g., a faulty ignition coil, sensor, or wiring), replacing just the module may not resolve the problem. A thorough diagnostic check is advisable before purchasing.

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### **Conclusion**

The Mercruiser 390-7804A3/15248T02 ignition control module/amplifier is a **highly recommended replacement part** for engines experiencing ignition-related failures. Its direct-fit design, reliability, and cost-effectiveness make it a practical solution for restoring engine performance. However, buyers should prioritize purchasing from **authorized dealers or trusted suppliers** to avoid counterfeit parts. Additionally, ensuring the root cause of the issue is addressed (e.g., checking wiring, sensors, and connections) will maximize the part s effectiveness.

For most boat owners facing persistent starting or running issues, this module is a **worthwhile investment** that can save money in the long run by preventing more extensive engine damage. If unsure about installation or diagnostics, consulting a marine mechanic is advisable to confirm the problem and ensure proper replacement.

### **Recommendation**

- **Buy from a reputable source** (e.g., Mercruiser dealership, authorized marine parts distributor, or well-reviewed online retailers).

- **Verify the part number** to ensure it matches your engine model exactly.

- **Test the engine after installation** to confirm the issue is resolved.

- **Consider professional installation** if you lack experience with marine electrical systems.

- **Maintain the module** by keeping it dry (especially in saltwater environments) and checking connections periodically.

This part is a **solid, cost-effective fix** for ignition control problems in Mercruiser engines, provided it is sourced and installed correctly.

Details:

GM 305 V-8 1981 1986 5907058 thru 0B522505. It was removed from a running 5.7L MerCruiser and has been properly stored. Please match part numbers, measurements, and compatibility with your engine or drive model. Part Numbers: 390-7804A3 15248T02.

This is an original MerCruiser electronic ignition component, not aftermarket. OEM MerCruiser part Freshwater use only Tested on a running engine prior to removal Ready install. 230 MIE 4 BBL.

part #: 3907804a315248t02 prices

• $100.00-$249.00

specifications ignitionstartin:

• brand: Mercruiser
• mpn: 390-7804a3/15248t02
• part type: Ignition Control Module Amplifier

seller ignitionstartin:

• # reviews: 20
• rating: 100.0%
• city: Broadalbin, New York

payments ignitionstartin:

• credit card: Mastercard
• wallet: Google-pay
• other

offer ignitionstartin:

• sold: 0
• options: Ship-to-home
• started: February 10, 2026
• quantity: 1
• best offers: True
• availability: In Stock

returns ignitionstartin:

• policy: No Returns

shipping ignitionstartin:

• type: Calculated
• carrier: USPS
• cost: $10.41
• service: USPS Ground Advantage
• class: Standard
• transit: 4-13 Days

general ignitionstartin:

• Boat Parts > Inboard Engines Components > Ignition Starting Systems
• condition: Used

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