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Engine Control Module (ECM)

This photo shows the same type of part you'll receive. Since each used part has its own wear and scratches, yours may look slightly different. Check the product notes for details about the condition of this specific part.

OEM Engine Control Module (ECM) for 2003-2006 BMW

Only 2 left in stock

$87.95

⚠️ ELECTRONIC MODULE NOTICE

This module may require programming to your vehicle by a dealer or qualified technician with professional diagnostic equipment.

Ships in a sealed inspection bag for visual inspection
Returns not accepted if inspection bag has been opened
"Needs programming" is not grounds for return
If told the module "won't program," contact us before returning
Defective units replaced ONLY ONCE, under warranty

ℹ️ Product Notes

This is a used part. It is the main Engine Control Module (ECM). This module ran well before it was removed. This part is for vehicles built starting in August. It does not have the high speed synchronization feature. Note: This computer module may need to be reprogrammed by a service center. Modules can only be reprogrammed a limited number of times.

This part must be programmed to your car by a professional. It only fits cars built after August 2003. Check the sticker on your driver's door for the build date.

Condition: Excellent (A)

Like new, minimal to no wear

86,810 miles

Odometer reading when part was removed

See All Other Engine Control Module (ECM)s

SKU #

3949701-03906-095

Why Buy Used OEM Parts?

✓ Quality-Verified: Every used OEM part we sell has been professionally inspected and tested to ensure it meets our quality standards. While it may show some cosmetic wear from previous use, it's fully functional and ready to install.

✓ Original Equipment: This is a genuine OEM (Original Equipment Manufacturer) part - the exact same part that came with your vehicle from the factory. It's designed specifically for your make and model, ensuring perfect fitment and performance.

✓ Works Like New: Despite some visual wear, this part will perform just as well as a brand new one. The internal components and functionality are intact, giving you the same reliability you'd expect from OEM quality.

✓ Significant Savings: Save 50-80% compared to buying new! Used OEM parts offer exceptional value - you get factory quality at a fraction of the cost. It's the smart choice for budget-conscious vehicle owners who won't compromise on quality.

✓ Risk-Free Purchase: We stand behind our used parts with a generous 6-month warranty, 30-day returns, and 100% money-back guarantee. If it doesn't work out for any reason, simply return it for a full refund. You have nothing to lose!

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Vehicle Fitment Guide

This part fits the following vehicles:

BMW

325Ci 2003-2006 (tapclick to expand)(tapclick to hide)

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SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
Base	Convertible	2003 - 2006	L6 2.5L	RWD \| Automatic & Manual \| Fits models built after August 2003
Base	Coupe	2003 - 2006	L6 2.5L	RWD \| Automatic & Manual \| Fits models built after August 2003
		2004 - 2005

325i 2003-2005 (tapclick to expand)(tapclick to hide)

Swipe left/right to see more info

SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
Base	Sedan	2003 - 2005	L6 2.5L	RWD \| Automatic & Manual \| Fits models built after August 2003
Base	Wagon	2003 - 2005	L6 2.5L	RWD \| Automatic & Manual \| Fits models built after August 2003
		2004

325xi 2003-2005 (tapclick to expand)(tapclick to hide)

Swipe left/right to see more info

SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
Base	Sedan	2003 - 2005	L6 2.5L	AWD \| Automatic & Manual \| Fits models built after August 2003
Base	Wagon	2003 - 2005	L6 2.5L	AWD \| Automatic & Manual \| Fits models built after August 2003
		2004

330Ci 2003-2006 (tapclick to expand)(tapclick to hide)

Swipe left/right to see more info

SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
Base	Convertible	2003 - 2006	L6 3.0L	RWD \| Automatic & Manual \| Fits models built after August 2003
Base	Coupe	2003 - 2006	L6 3.0L	RWD \| Automatic & Manual \| Fits models built after August 2003
M	Convertible	2005	L6 3.0L	RWD \| Automatic & Manual \| Fits models built after August 2003
M	Coupe	2005	L6 3.0L	RWD \| Automatic & Manual \| Fits models built after August 2003
		2004

330i 2003-2005 (tapclick to expand)(tapclick to hide)

Swipe left/right to see more info

SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
Base	Sedan	2003 - 2005	L6 3.0L	RWD \| Automatic & Manual \| Fits models built after August 2003
M	Sedan	2005	L6 3.0L	RWD \| Automatic & Manual \| Fits models built after August 2003
		2004

330xi 2003-2005 (tapclick to expand)(tapclick to hide)

Swipe left/right to see more info

SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
Base	Sedan	2003 - 2005	L6 3.0L	AWD \| Automatic & Manual \| Fits models built after August 2003
		2004

525i 2004-2005 (tapclick to expand)(tapclick to hide)

Swipe left/right to see more info

SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
Base	Sedan	2004 - 2005	L6 2.5L	RWD \| Automatic & Manual

530i 2004-2005 (tapclick to expand)(tapclick to hide)

Swipe left/right to see more info

SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
Base	Sedan	2004 - 2005	L6 3.0L	RWD \| Automatic & Manual

X3 2004-2006 (tapclick to expand)(tapclick to hide)

Swipe left/right to see more info

SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
2.5i	SUV	2004 - 2006	L6 2.5L	AWD \| Automatic & Manual
3.0i	SUV	2004 - 2006	L6 3.0L	AWD \| Automatic & Manual
		2005

Z4 2003-2005 (tapclick to expand)(tapclick to hide)

Swipe left/right to see more info

SubmodelSUB- MODEL	Body Style	Years	Engine	Attributes
2.5i	Convertible	2003 - 2005	L6 2.5L	RWD \| Automatic & Manual \| Fits models built after August 2003
3.0i	Convertible	2003 - 2005	L6 3.0L	RWD \| Automatic & Manual \| Fits models built after August 2003
		2004

⚠️ Important: Please verify your vehicle's year, make, model, and specifications before ordering. If you're unsure about fitment, contact our customer service team for assistance.

Policies

Shipping & Handling

Standard shipping: 3-7 business days via UPS Ground
Parts are carefully packaged to prevent damage during transit

Returns (30 Days)

We accept returns within 30 days of delivery for this part.

Defective parts: We will replace the part or issue a refund at our discretion
Electronic parts: Must be returned with the sealed inspection bag unopened. The clear bag allows full visual inspection before opening. Once opened, electronic parts can only be exchanged for a replacement if defective — no refunds
Programming: "Needs to be programmed to my vehicle" is not a valid return reason. Many modules require dealer programming — we're happy to help connect you with resources if your dealer says it's not programmable
Return shipping: We cover return shipping as part of our 100% money-back guarantee
Parts must be returned in original packaging and unmodified condition
Poorly packaged returns that arrive damaged will not be credited

6-Month Warranty

All used parts include a 6-month warranty from the date of purchase.

If your part fails within 6 months, we will send a replacement
Refunds are only issued if we cannot provide a suitable replacement
Warranty covers defects — not installation errors, misuse, or damage after installation

Note: Warranty is for replacement, not refund. A part failing on day 80? We'll replace it. But the return window for refunds is 30 days.

Damaged in Shipping?

If your part arrives damaged:

Stop immediately — do not install the part
Keep all original packaging and boxes
Take clear photos of the damage and packaging
Contact us within 48 hours of delivery

We will handle the carrier claim. You are not responsible for shipping damage — we just need your help documenting it.

Order Cancellation

Orders can be cancelled before shipment for a full refund. Once shipped, cancellations follow our return policy.

Symptoms & Diagnosis

Warning Signs of a Failing Engine Control Module (ECM)

Engine misfires or runs rough
Stalling or difficulty starting
Check Engine Light is on
Poor fuel economy
Transmission shifting problems
Car won't start at all

How to Test if the ECM is the Problem

Check the basics: Make sure the battery is good, the spark plugs are firing, and there are no vacuum leaks.
Scan for codes: Use an OBD-II scanner to read the trouble codes stored in the ECM. This can help pinpoint the problem.
Inspect wiring: Check the wiring harness and connectors for any damage, corrosion, or loose connections.
Consult a mechanic: A qualified mechanic can perform more advanced tests to diagnose the ECM.

Common Failure Causes

Overheating
Voltage spikes
Water damage
Physical damage
Age and wear

Buyer's Checklist

What to Look For When Buying

Compatibility: Verify the ECM is designed for your specific vehicle year, make, and model.
Condition: If buying a used ECM, check for any signs of damage or corrosion.
Warranty: Look for a warranty to protect your investment.
Reputation: Buy from a reputable seller.

Quality Indicators

Feature	Used OEM	New Aftermarket
Source	Original equipment from the manufacturer	Third-party manufacturer
Testing	Typically tested and inspected	New, but may not have been tested in a vehicle
Reliability	Generally reliable, as it's a factory part	Can vary depending on the manufacturer
Price	Lower than new aftermarket	Higher than used OEM

What's Typically Included

The ECM itself
Sometimes, installation instructions (check with the seller)

Installation Overview

Difficulty Level and Estimated Time

Difficulty: Medium
Estimated Time: 1-3 hours

Special Tools Needed

Basic hand tools (sockets, wrenches, screwdrivers)
OBD-II scanner
Possibly a code reader/programmer (depending on the vehicle and ECM)

Critical Steps and Tips

Disconnect the battery: This is crucial for safety.
Locate the ECM: It's usually under the hood or under the dashboard.
Disconnect the wiring harness: Be careful not to damage the connectors.
Remove the old ECM: Unbolt it from its mounting bracket.
Install the new ECM: Bolt it in place and reconnect the wiring harness.
Reconnect the battery:
Program the ECM: Some ECMs need to be programmed to your vehicle. This may require a specialized tool or a trip to a mechanic.

DIY or Professional Installation?

DIY is possible if you have mechanical experience and the necessary tools.
Professional installation is recommended if you're not comfortable working on your car or if the ECM needs to be programmed.

Buying Options

Compare: Used OEM, New Aftermarket

Feature	Used OEM	New Aftermarket
Pros	Genuine factory part, tested and inspected, lower price, reliable (as it's a factory part)	Brand new, readily available
Cons	May have some wear and tear, availability may be limited	Quality can vary, may not be as reliable as OEM
Best For	Budget-conscious buyers who want a reliable replacement part.	Buyers who prefer a brand new part and don't mind paying a bit more.

Used OEM

Best value for your money.
Genuine factory parts, ensuring proper fit and function.
Tested and inspected to ensure they're working properly.
Significantly lower prices than new parts.

New Aftermarket

Brand new parts from third-party manufacturers.
Built to meet or exceed OE specifications.
A good option if you prefer a new part.

Typical Lifespan

How Long This Part Normally Lasts

An ECM can last for the life of the vehicle, often 10-15 years or more.

Factors That Affect Longevity

Overheating
Voltage spikes
Water damage
Physical damage
Proper maintenance

Price Ranges

Budget vs Mid-Range vs Premium Options

Used OEM: $150 - $350
New Aftermarket: $300 - $600

Labor Cost Considerations

Labor costs can vary depending on the mechanic and the complexity of the job.
Expect to pay $100 - $300 for labor.

Total Job Cost Estimates

Used OEM: $250 - $650 (parts and labor)
New Aftermarket: $400 - $900 (parts and labor)

Vehicle-Specific Notes

Known Issues

Some models have issues with the ECM due to heat.
Check engine light issues related to O2 sensors can sometimes be related to the ECM.

TSBs or Common Complaints

Check for any Technical Service Bulletins (TSBs) related to the ECM on your specific vehicle.
Common complaints include intermittent stalling and misfires.

Verification After Install

How to Confirm Proper Operation

Start the engine and let it idle.
Check for any unusual noises or vibrations.
Drive the car and see how it performs.
Use an OBD-II scanner to check for any new trouble codes.

What to Look/Listen For

Smooth engine operation
Proper shifting
No Check Engine Light
Good fuel economy

FAQ

Q: Will this ECM need to be programmed?
A: Some ECMs need to be programmed to your vehicle's VIN. Check with the seller or a mechanic to see if programming is required.

Q: How do I know if my ECM is bad?
A: Common symptoms include engine misfires, stalling, difficulty starting, and a Check Engine Light.

Q: Can I install this ECM myself?
A: Yes, if you have mechanical experience and the necessary tools. However, professional installation is recommended if you're not comfortable working on your car.

Q: What if the ECM I receive is defective?
A: Buy from a seller with a good return policy.

Q: How can I prevent my ECM from failing again?
A: Address any underlying issues that may have caused the original ECM to fail, such as overheating or voltage spikes.

Part Specifications

OEM Part Numbers:

BMW: 12147527015, 12147533652, 12147549095, 12147549133, 12147549390, 12147561383, 7549095

Fits Years: 2003 2004 2005 2006

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