# 826800A9 Mercury Detonation Controller | Genuine Used Part

🔧 Product Description

  

Genuine Mercury Detonation Controller Assembly - Part Number: 826800A9

  

A genuine Mercury detonation controller assembly used on selected Mercury 2.5L V6 EFI two-stroke ignition systems. This module forms part of the knock / detonation protection circuit and helps manage ignition timing response when detonation is detected.

  

⚙️ Key Features

  

• Genuine Mercury detonation controller assembly

• Correct Mercury part number 826800A9

• Related to 826800A7 and 826800A8 detonation-control references

• Used on selected Mercury 2.5L V6 EFI two-stroke applications

• Must be matched by engine serial number, wiring layout and ignition-system configuration

  

🔄 Supersession & Cross Reference

  

OEM Supersession Chain:

  

• 826800A9 later detonation controller reference

• 826800A8 earlier / related detonation controller reference

• 826800A7 earlier / related detonation controller reference

  

OEM / Related Numbers:

  

• 826800A9

• 826800A8

• 826800A7

• Detonation controller assembly

• Detonation control module

• Knock control module

• Related Mercury detonation sensor circuit reference

• Related Mercury V6 timing / advance control family reference

  

Aftermarket / Verified Equivalents:

  

• No aftermarket equivalent

  

🚤 Compatibility

  

Commonly used on:

  

• Mercury V6 EFI two-stroke detonation-control systems

  

Typically suits:

  

• Engine models:

• Mercury 150 EFI Pro Max 2.5L detonation-control applications where specified

• Mercury 200 EFI Pro Max 2.5L detonation-control applications where specified

• Mercury 200 EFI Super Magnum 2.5L detonation-control applications where specified

• Mercury V-150 MAG / EFI applications using detonation controller modules

• Mercury V-150 XRI EFI applications using detonation controller modules

• Mercury V-175 SKI / MAG / EFI applications using detonation controller modules

• Mercury V-175 XRI EFI applications using detonation controller modules

• Mercury V-200 MAG / EFI applications using detonation controller modules

• Mercury V-200 XRI EFI applications using detonation controller modules

• Mercury V-220 Laser EFI applications using detonation controller modules

• Mercury 200HP EFI 2-stroke applications around 2000 model year using 826800A9

• Mercury 200HP EFI 2-stroke serial 0T148227 donor-family reference using 826800A9

  

• HP Range: commonly 150HP - 220HP Mercury V6 EFI two-stroke applications where specified

• Engine Type: Mercury 2.5L V6 EFI two-stroke outboard

• System Type: Detonation / knock protection control module

• Serial Note: Confirm engine serial number, detonation sensor, switch-box bias circuit and ignition module layout before installation.

  

🔌 Function

  

The detonation controller monitors detonation-related input and interfaces with the ignition system to help protect the engine from damaging knock by altering ignition control when required.

  

Common signs of failure:

  

• Detonation-control fault after sensor and wiring checks

• Unstable timing response

• Engine warning or performance reduction related to knock circuit

• Intermittent loss of timing control

• Fault isolated to detonation module after switch-box and harness testing

• Heat or vibration-related module failure

• Corrosion or broken wires at controller plug

  

📦 Condition

  

• Genuine used part

• Removed from running engine where applicable

• In good working condition unless otherwise stated

## Details

- **Price:** 135.0 AUD
- **Vendor:** Sawley's Auto and Marine
- **Tags:** Sawley’s AAM Used Parts – Electronic Components | ECU CDI & Electrical Parts

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 135.00 AUD | In stock |

## Images

- 826800A9 Mercury Detonation Controller | Genuine Used Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/826800a9-mercury-detonation-controller-genuine-used-part)
> Updated: 2026-06-29