OEM Engine Control Module (ECM) for 2016-2018 Cadillac, Chevrolet, & GMC - Rear
$
89
.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
Product Notes
This is a used Engine Control Module (ECM) in like-new condition with no damage. It is a programmable control module. This part fits vehicles with a 5.3L engine, 6-speed automatic transmission, and rear-wheel drive. It is for 4-door models.
This module is for vehicles with the 6.2L V8 engine ONLY. This module MUST be programmed to your vehicle's VIN to function. Please verify that your original module has the exact part number 12678939 before ordering.
This module is for vehicles with the 6.2L V8 engine ONLY. This module MUST be programmed to your vehicle's VIN to function. Please verify that your original module has the exact part number 12678939 before ordering.
Condition: Excellent (A)
Like new, minimal to no wear
52,800 miles
Odometer reading when part was removed
1 Other Matching Unit Available
Same part, different stock options.
Why Buy Used OEM Parts?
- ✓ Quality-Verified: Every used OEM part we sell has been professionally inspected and tested. While it may show some cosmetic wear, it's fully functional and ready to install.
- ✓ Original Equipment: This is a genuine OEM part — the exact part that came with your vehicle from the factory. Perfect fitment and performance.
- ✓ Works Like New: Despite visual wear, internal components and functionality are intact. Same reliability you'd expect from OEM quality.
- ✓ Significant Savings: Save 50–80% vs. new. Factory quality at a fraction of the cost — the smart choice for budget-conscious owners.
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Vehicle Fitment Guide
This part fits the following vehicles:
Cadillac
5 models(tapclick to hide)
ATS
2017
(tapclick to hide)
Swipe left/right to see more info
| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Base | Coupe | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic & Manual |
| Base | Sedan | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic & Manual |
| Base | Coupe | 2017 | L4 2.5L | AWD/RWD | Automatic & Manual |
| Base | Sedan | 2017 | L4 2.5L | AWD/RWD | Automatic & Manual |
| Luxury | Coupe | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic & Manual |
| Luxury | Sedan | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic & Manual |
| Luxury | Coupe | 2017 | L4 2.5L | AWD/RWD | Automatic & Manual |
| Luxury | Sedan | 2017 | L4 2.5L | AWD/RWD | Automatic & Manual |
| Performance | Coupe | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic & Manual |
| Performance | Sedan | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic & Manual |
| Performance | Coupe | 2017 | V6 3.6L | AWD/RWD | Automatic & Manual |
| Performance | Sedan | 2017 | V6 3.6L | AWD/RWD | Automatic & Manual |
| Premium Luxury | Coupe | 2017 | V6 3.6L | AWD/RWD | Automatic |
| Premium Luxury | Sedan | 2017 | V6 3.6L | AWD/RWD | Automatic |
| Premium Performance | Coupe | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic & Manual |
| Premium Performance | Sedan | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic & Manual |
| Premium Performance | Coupe | 2017 | V6 3.6L | AWD/RWD | Automatic & Manual |
| Premium Performance | Sedan | 2017 | V6 3.6L | AWD/RWD | Automatic & Manual |
| V | Coupe | 2017 | V6 3.6L Turbo | RWD | Automatic & Manual |
| V | Sedan | 2017 | V6 3.6L Turbo | RWD | Automatic & Manual |
CTS
2017
(tapclick to hide)
Swipe left/right to see more info
| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Base | Sedan | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic |
| Luxury | Sedan | 2017 | L4 2.0L Turbo | AWD/RWD | Automatic |
| Luxury | Sedan | 2017 | V6 3.6L | AWD/RWD | Automatic |
| Premium | Sedan | 2017 | V6 3.6L | AWD/RWD | Automatic |
| Premium Luxury | Sedan | 2017 | V6 3.6L | AWD/RWD | Automatic |
| V | Sedan | 2017 | V8 6.2L Supercharged | RWD | Automatic |
| Vsport | Sedan | 2017 | V6 3.6L Turbo | RWD | Automatic |
| Vsport Premium Luxury | Sedan | 2017 | V6 3.6L Turbo | RWD | Automatic |
Escalade
2017
(tapclick to hide)
Swipe left/right to see more info
| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Base | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
| Luxury | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
| Platinum | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
| Premium | SUV | 2017 | V8 6.2L | 4WD | Automatic |
| Premium Luxury | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
Escalade ESV
2017
(tapclick to hide)
Swipe left/right to see more info
| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Base | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
| Luxury | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
| Platinum | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
| Premium | SUV | 2017 | V8 6.2L | 4WD | Automatic |
| Premium Luxury | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
XTS
2017
(tapclick to hide)
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| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Base | Sedan | 2017 | V6 3.6L | FWD | Automatic |
| Livery | Hearse | 2017 | V6 3.6L | FWD | Automatic |
| Livery | Limousine | 2017 | V6 3.6L | FWD | Automatic |
| Luxury | Sedan | 2017 | V6 3.6L | AWD/FWD | Automatic |
| Platinum | Sedan | 2017 | V6 3.6L | AWD/FWD | Automatic |
| Premium | Sedan | 2017 | V6 3.6L | AWD/FWD | Automatic |
| Premium Luxury | Sedan | 2017 | V6 3.6L | AWD/FWD | Automatic |
| Vsport Platinum | Sedan | 2017 | V6 3.6L Turbo | AWD | Automatic |
| Vsport Premium Luxury | Sedan | 2017 | V6 3.6L Turbo | AWD | Automatic |
Chevrolet
3 models(tapclick to hide)
Camaro
2017
(tapclick to hide)
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| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| SS | Convertible | 2017 | V8 6.2L | RWD | Automatic & Manual | engine_size: include 6.2L; fuel_type: include GAS |
| SS | Coupe | 2017 | V8 6.2L | RWD | Automatic & Manual | engine_size: include 6.2L; fuel_type: include GAS |
| ZL1 | Convertible | 2017 | V8 6.2L Supercharged | RWD | Automatic & Manual | engine_size: include 6.2L; fuel_type: include GAS |
| ZL1 | Coupe | 2017 | V8 6.2L Supercharged | RWD | Automatic & Manual | engine_size: include 6.2L; fuel_type: include GAS |
Corvette
2017
(tapclick to hide)
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| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Grand Sport | Convertible | 2017 | V8 6.2L | RWD | Automatic & Manual |
| Grand Sport | Coupe | 2017 | V8 6.2L | RWD | Automatic & Manual |
| Stingray | Convertible | 2017 | V8 6.2L | RWD | Automatic & Manual |
| Stingray | Coupe | 2017 | V8 6.2L | RWD | Automatic & Manual |
| Z06 | Convertible | 2017 | V8 6.2L Supercharged | RWD | Automatic & Manual |
| Z06 | Coupe | 2017 | V8 6.2L Supercharged | RWD | Automatic & Manual |
Silverado 1500
2016-2018
(tapclick to hide)
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| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| High Country | Crew Cab Pickup | 2016 - 2018 | V8 6.2L | RWD/4WD | Automatic |
| LTZ | Crew Cab Pickup | 2016 - 2018 | V8 6.2L | RWD/4WD | Automatic |
| LTZ | Extended Cab Pickup | 2016 - 2018 | V8 6.2L | RWD/4WD | Automatic |
GMC
3 models(tapclick to hide)
Sierra 1500
2016-2018
(tapclick to hide)
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| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Denali | Crew Cab Pickup | 2016 - 2018 | V8 6.2L | RWD/4WD | Automatic |
| SLT | Crew Cab Pickup | 2016 - 2018 | V8 6.2L | RWD/4WD | Automatic |
| SLT | Extended Cab Pickup | 2016 - 2018 | V8 6.2L | RWD/4WD | Automatic |
Yukon
2017
(tapclick to hide)
Swipe left/right to see more info
| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Denali | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
Yukon XL
2017
(tapclick to hide)
Swipe left/right to see more info
| SubmodelSUB- MODEL |
Body Style | Years | Engine | Attributes |
|---|---|---|---|---|
| Denali | SUV | 2017 | V8 6.2L | RWD/4WD | Automatic |
Verify before ordering — please confirm your vehicle's year, make, model and sub-model specifications before placing your order. If anything is unclear, our customer service team is available to help.
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.
Go-Parts Garage · Featured Guide
2016-2018 GM Truck & Cadillac ECM Guide: Stalling, No-Start, and Programming
Diagnose and understand Engine Control Module (ECM) failures in the 2016-2018 Silverado, Sierra, and various 2017 Cadillac models, including the critical, non-negotiable programming requirements.
Read Full Guide →⚠️ Related Trouble Codes (OBD-II)
50 matching guidesIf your scan tool is showing one of these trouble codes, this part is a common fix. Each guide explains the code, how to diagnose it, and exactly what to replace.
P0087
2010-2017 Chevrolet SILVERADO 1500
P0148
2007-2024 Chevrolet Silverado 1500
P0191
2010-2016 Gmc SIERRA 1500
P0308
2013-2019 Cadillac XTS
P0333
2014-2020 Gmc YUKON XL
P0333
2015-2019 Gmc YUKON DENALI
P0601
2015-2018 Cadillac ESCALADE
P0601
2015-2018 Chevrolet SUBURBAN
P0601
2015-2018 Gmc YUKON
P0601
2016-2018 Gmc SIERRA 1500
P0601
2015-2018 Chevrolet TAHOE
P0601
2015-2018 Chevrolet SILVERADO 1500
↑ A single part can trigger multiple related trouble codes. Each guide is vehicle- and code-specific.
Miscellaneous Information
OEM Part Numbers:
Other: 12674052, 12674472, 12678815, 12678939, 12686382
Fits Years: 2016 2017 2018
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Warranty
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This part ships with a 6-month warranty. If it doesn't fit or stops working, we replace or refund — no hassle.
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4.9
1,451 verified reviews
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